WorldWideScience

Sample records for bioconversion

  1. Bioconversion reactor

    Science.gov (United States)

    McCarty, Perry L.; Bachmann, Andre

    1992-01-01

    A bioconversion reactor for the anaerobic fermentation of organic material. The bioconversion reactor comprises a shell enclosing a predetermined volume, an inlet port through which a liquid stream containing organic materials enters the shell, and an outlet port through which the stream exits the shell. A series of vertical and spaced-apart baffles are positioned within the shell to force the stream to flow under and over them as it passes from the inlet to the outlet port. The baffles present a barrier to the microorganisms within the shell causing them to rise and fall within the reactor but to move horizontally at a very slow rate. Treatment detention times of one day or less are possible.

  2. Photosynthesis and Bioconversion

    International Nuclear Information System (INIS)

    Broda, E.

    1983-01-01

    This text summarises a talk held by Engelbert Broda at a conference on non-convential energy sources. The talk about photosynthesis and bioconversion is devided in 6 sections: the great physicist and photosynthesis; the influence of photosynthesis on the biosphere (in the past, present and future); the light reactions in photosynthesis; the dark reactions in photosynthesis; bioconversion; respiration and photorespiration. (nowak)

  3. Bioconversion of Cheese Waste (Whey)

    Energy Technology Data Exchange (ETDEWEB)

    Bohnert, G.W.

    1998-03-11

    The US dairy industry produces 67 billion pounds of cheese whey annually. A waste by-product of cheese production, whey consists of water, milk sugar (lactose), casein (protein), and salts amounting to about 7% total solids. Ultrafiltration is used to concentrate cheese whey into a protein-rich foodstuff; however, it too produces a waste stream, known as ''whey permeate,'' (rejected water, lactose, and salts from the membrane). Whey permeate contains about 4.5% lactose and requires treatment to reduce the high BOD (biological oxygen demand) before disposal. Ab Initio, a small business with strong chemistry and dairy processing background, desired help in developing methods for bioconversion of whey permeate lactose into lactic acid. Lactic acid is an organic acid primarily used as an acidulant in the food industry. More recently it has been used to produce polylactic acid, a biodegradable polymer and as a new method to treat meat carcasses to combat E. coli bacteria. Conversion of whey permeate to lactic acid is environmentally sound because it produces a valued product from an otherwise waste stream. FM&T has expertise in bioconversion processes and analytical techniques necessary to characterize biomass functions. The necessary engineering and analytical services for pilot biomass monitoring, process development, and purification of crude lactic acid were available at this facility.

  4. Bioconversion of Cheese Waste (Whey)

    International Nuclear Information System (INIS)

    Bohnert, G.W.

    1998-01-01

    The US dairy industry produces 67 billion pounds of cheese whey annually. A waste by-product of cheese production, whey consists of water, milk sugar (lactose), casein (protein), and salts amounting to about 7% total solids. Ultrafiltration is used to concentrate cheese whey into a protein-rich foodstuff; however, it too produces a waste stream, known as ''whey permeate,'' (rejected water, lactose, and salts from the membrane). Whey permeate contains about 4.5% lactose and requires treatment to reduce the high BOD (biological oxygen demand) before disposal. Ab Initio, a small business with strong chemistry and dairy processing background, desired help in developing methods for bioconversion of whey permeate lactose into lactic acid. Lactic acid is an organic acid primarily used as an acidulant in the food industry. More recently it has been used to produce polylactic acid, a biodegradable polymer and as a new method to treat meat carcasses to combat E. coli bacteria. Conversion of whey permeate to lactic acid is environmentally sound because it produces a valued product from an otherwise waste stream. FM and T has expertise in bioconversion processes and analytical techniques necessary to characterize biomass functions. The necessary engineering and analytical services for pilot biomass monitoring, process development, and purification of crude lactic acid were available at this facility

  5. Bioconversion of Rebaudioside I from Rebaudioside A

    Directory of Open Access Journals (Sweden)

    Indra Prakash

    2014-10-01

    Full Text Available To supply the increasing demand of natural high potency sweeteners to reduce the calories in food and beverages, we have looked to steviol glycosides. In this work we report the bioconversion of rebaudioside A to rebaudioside I using a glucosyltransferase enzyme. This bioconversion reaction adds one sugar unit with a 1→3 linkage. We utilized 1D and 2D NMR spectroscopy (1H, 13C, COSY, HSQC-DEPT, HMBC, 1D TOCSY and NOESY and mass spectral data to fully characterize rebaudioside I.

  6. Lignocellulose biotechnology: issues of bioconversion and enzyme ...

    African Journals Online (AJOL)

    Lignocellulose biotechnology: issues of bioconversion and enzyme production. ... and secondly to highlight some of the modern approaches which potentially could be used to tackle one of the major impediments, namely high enzyme cost, to speed-up the extensive commercialisation of the lignocellulose bioprocessing.

  7. Encapsulates for Food Bioconversions and Metabolite Production

    Science.gov (United States)

    Breguet, Véronique; Vojinovic, Vojislav; Marison, Ian W.

    The control of production costs in the food industry must be very strict as a result of the relatively low added value of food products. Since a wide variety of enzymes and/or cells are employed in the food industry for starch processing, cheese making, food preservation, lipid hydrolysis and other applications, immobilization of the cells and/or enzymes has been recognized as an attractive approach to improving food processes while minimizing costs. This is due to the fact that biocatalyst immobilization allows for easier separation/purification of the product and reutilization of the biocatalyst. The advantages of the use of immobilized systems are many, and they have a special relevance in the area of food technology, especially because industrial processes using immobilized biosystems are usually characterized by lower capital/energy costs and better logistics. The main applications of immobilization, related to the major processes of food bioconversions and metabolite production, will be described and discussed in this chapter.

  8. Direct Bioconversion of Oil Palm Empty Fruit Bunches for Bioethanol Production By Solid State Bioconversion

    Directory of Open Access Journals (Sweden)

    Nassereldeen Ahmed Kabbashi

    2010-09-01

    Full Text Available The bioethanol production was conducted by utilizing agriculture waste, palm oil empty fruit bunches (EFB with the aid of T. harzianum and yeast, Saccharomyces cerevisiae using solid state bioconversion method. The compatibility of various fungal strains was done as to develop the direct bioconversion process of compatible mixed culture. Analyzes such ethanol estimation, reducing sugar and glucosamine as growth indicator were conducted in order to select the best experimented run for optimization. The optimization of process conditions, by using central composite design (CCD was carried out. Optimization of process condition was done with varied level of moisture content, pH, inoculum size, concentration of co-substrate (wheat flour and mineral solutions. Statistical analysis showed that the optimum process condition for moisture content was 50% (v/w, pH of 4, inoculum size of 10% (v/v, concentration of wheat flour of 1% (v/v and mineral solutions 1%(v/v. In this study, the application levels of the methods of environmental management in regards to the maximum production were determined. The final optimization with the developed process conditions indicated that the maximum production was increased from 14.315 (v/v to 34.785(v/v.

  9. Bioconversion of organic wastes for fuel and manure

    International Nuclear Information System (INIS)

    Jain, M.C.

    1993-01-01

    Major source of fuel in rural areas is still fire wood, cowdung and crop residues. Cowdung and crop residues can be effectively used as manure too. Bioconversion of organic wastes for fuel and manure can solve the twin problems. The paper deals with various kinds of organic wastes used as fuel, manure and for both, other organic wastes as alternate and supplemental feedstocks, impact of their bioconversion on rural energy and environment, dry fermentation technology, manurial value of the biogas slurry, etc. Important constraints in popularizing the biogas programme have been mentioned and their remedial measures have also been suggested. (author). 32 refs., 4 tabs., 3 figs

  10. Bioconversion of Egypt's agricultural wastes into biogas and compost

    Czech Academy of Sciences Publication Activity Database

    Elfeki, M.; Elbestawy, E.; Tkadlec, Emil

    2017-01-01

    Roč. 26, č. 6 (2017), s. 2445-2453 ISSN 1230-1485 Institutional support: RVO:68081766 Keywords : agricultural wastes * biogas in Egypt * bioconversion * compost in Egypt * organic wastes Subject RIV: DM - Solid Waste and Recycling OBOR OECD: Environmental sciences (social aspects to be 5.7) Impact factor: 0.793, year: 2016

  11. Bioconversion of rape straw into a nutritionally enriched substrate by ...

    African Journals Online (AJOL)

    This work aims to select biological treatments and conditions for the bioconversion of rape straw by the mixed-strain fermentation of Ganoderma lucidum and yeasts (Saccharomyces cerevisiae, Candida tropicalis and Candida utilis), into an enriched substrate with increased crude protein and digestibility. Orthogonal ...

  12. Bioconversion of ferulic acid to vanillin by combined action of ...

    African Journals Online (AJOL)

    Ability of 10 fungi strains for the degradation of ferulic acid and production of vanillic acid was examined. The findings suggested that all the fungi were able to degrade ferulic acid via different pathways producing variety of products. Vanillic acid was the main bioconversion product for all the fungi strains. Aspergillus niger ...

  13. Bioconversion of sugar beet pulps and by-products

    Energy Technology Data Exchange (ETDEWEB)

    Lescure, J.P.; Bourlet, P.

    A new technology for biogas and energy supply by anaerobic digestion of wet vegetal substrats was studied. It was a two step anaerobic process, each resulting from numerous fermentative reactions. About 88% of the pulp substrat can be converted into gas and a volumic load of 7 kg.m/sup 3/ of dry solids was converted in 24 hours. Many technological problems were encountered with beet trash digestion. It was not tested with high loads, but bioconversion rate was about 75%.

  14. Biomass pyrolysis liquid to citric acid via 2-step bioconversion.

    Science.gov (United States)

    Yang, Zhiguang; Bai, Zhihui; Sun, Hongyan; Yu, Zhisheng; Li, Xingxing; Guo, Yifei; Zhang, Hongxun

    2014-12-31

    The use of fossil carbon sources for fuels and petrochemicals has serious impacts on our environment and is unable to meet the demand in the future. A promising and sustainable alternative is to substitute fossil carbon sources with microbial cell factories converting lignocellulosic biomass into desirable value added products. However, such bioprocesses require tolerance to inhibitory compounds generated during pretreatment of biomass. In this study, the process of sequential two-step bio-conversion of biomass pyrolysis liquid containing levoglucosan (LG) to citric acid without chemical detoxification has been explored, which can greatly improve the utilization efficiency of lignocellulosic biomass. The sequential two-step bio-conversion of corn stover pyrolysis liquid to citric acid has been established. The first step conversion by Phanerochaete chrysosporium (P. chrysosporium) is desirable to decrease the content of other compounds except levoglucosan as a pretreatment for the second conversion. The remaining levoglucosan in solution was further converted into citric acid by Aspergillus niger (A. niger) CBX-209. Thus the conversion of cellulose to citric acid is completed by both pyrolysis and bio-conversion technology. Under experimental conditions, levoglucosan yield is 12% based on the feedstock and the citric acid yield can reach 82.1% based on the levoglucosan content in the pyrolysis liquid (namely 82.1 g of citric acid per 100 g of levoglucosan). The study shows that P. chrysosporium and A. niger have the potential to be used as production platforms for value-added products from pyrolyzed lignocellulosic biomass. Selected P. chrysosporium is able to decrease the content of other compounds except levoglucosan and levoglucosan can be further converted into citric acid in the residual liquids by A. niger. Thus the conversion of cellulose to citric acid is completed by both pyrolysis and bio-conversion technology.

  15. Modelling the bioconversion of cellulose into microbial products: rate limitations

    Energy Technology Data Exchange (ETDEWEB)

    Asenjo, J A

    1984-12-01

    The direct bioconversion of cellulose into microbial products carried out as a simultaneous saccharification and fermentation has a strong effect on the rates of cellulose degradation because cellobiose and glucose inhibition of the reaction are circumvented. A general mathematical model of the kinetics of this bioconversion has been developed. Its use in representing aerobic systems and in the analysis of the kinetic limitations has been investigated. Simulations have been carried out to find the rate limiting steps in slow fermentations and in rapid ones as determined by the specific rate of product formation. The requirements for solubilising and depolymerising enzyme activities (cellulase and cellobiase) in these systems has been determined. The activity that have been obtained for fungal cellulases are adequate for the kinetic requirements of the fastest fermentative strains. The results also show that for simultaneous bioconversions where strong cellobiose and glucose inhibition is overcome, no additional cellobiase is necessary to increase the rate of product formation. These results are useful for the selection of cellolytic micro-organisms and in the determination of enzymes to be cloned in recombinant strains. 17 references.

  16. Bioconversion of poultry droppings for biogas and algal production

    Energy Technology Data Exchange (ETDEWEB)

    Mahadevaswamy, M.; Venkataraman, L.V.

    1986-01-01

    An integrated system for the bioconversion of poultry droppings for biogas production and utilization of the effluent for the production of the blue-green alga Spirulina platensis was studied. Poultry droppings produced 0.54 cubic m of biogas per kilogran of Total Solids (TS). The 2% TS biogas plant effluent as sole nutrient medium for Spirulina yielded 7-8 g dry algae a day. The biomass was harvested by filtration. The sundried algal biomass has been used as a poultry feed component. In economic terms the system appears promising. 18 references.

  17. Wastewaters from the bioconversion of biomass. Utilisation and treatment

    Energy Technology Data Exchange (ETDEWEB)

    Frings, R.M. (Forest Research Inst. (New Zealand)); Coombs, J. (CPL Scientific Ltd., Newbury (United Kingdom))

    1992-04-01

    Developed technology for the bioconversion of biomass into energy forms falls into two categories: biogasification and bioliquefaction. Biogasification is the anaerobic fermentation of organic matter by a mixed culture of organisms to produce a gaseous mixture of methane and carbon dioxide. Bioliquefaction is the use of a pure culture of organisms (mainly yeasts) to anaerobically ferment sugars into a range of liquid products with acetone, butanol, and ethanol being the most commonly produced. Biological processes have the advantage of occurring at ambient, or relatively low (35-60[sup o]C) temperature, at atmospheric pressure, in dilute substrate, in an aqueous environment. Conversion of raw material to gas or liquid fuel is generally incomplete, leaving the non-convertible residues (organic or inorganic) in solution. Hence, biological processes potentially generate large volumes of wastewater containing significant levels of pollutants. This review briefly describes the two bioconversion process routes and then considers each process separately in relation to the characteristics, utilisation and treatment of the specific wastewaters produced by the process. (author)

  18. Use of Aspergillus niger for bioconversion of apple distillery waste

    Energy Technology Data Exchange (ETDEWEB)

    Friedrich, J.; Cimerman, A.; Perdih, A.

    1983-01-01

    The bioconversion of waste material remaining after apple brandy distillation was investigated. Different cellulolytic fungi were tested for their ability to convert the waste organic substances into microbial biomass. An Aspergillus niger strain was chosen as the most convenient microorganism. By growing this mold on the apple slop the following results were obtained: filtration time was shortened by 30 times, reduction of the chemical oxygen demand in the liquid phase in the range of 50-80% depending on the substrate dilution and a dry filter cake enriched with fungal biomass to about 12 g/l containing up to 22% raw proteins and certain amounts of cellulolytic enzymes in the filtrate. The influence of the initial pH, the salt addition and the dilution of the substrate were studied as well. 12 references.

  19. Bioconversion of chicken wastes to value-added products

    Energy Technology Data Exchange (ETDEWEB)

    Barik, S; Forgacs, T; Isbister, J [ARCTECH, Inc., Alexandria, VA (United States)

    1991-01-01

    Increasing quantities of chicken waste concerns the poultry industry because of escalating disposal costs and the potential for environmental pollution. Biological conversion of these wastes to valuable products such as methane and/or chemical feed-stocks appears to be feasible. Biomethanation of chicken waste by a sewage sludge microbial consortium produced as much as 69 mol% methane in the gas phase. Acetic and propionic acids were the major acids produced during the bioconversion. Addition of chelating agents and other micro-nutrients enhanced methane production and shifted the ratios of intermediates accumulated. Preliminary data indicate that more than 60% of the chicken waste carbon was converted and that the nitrogen-rich residue may have potential as a soil additive. (author).

  20. Bioconversion Using Lactic Acid Bacteria: Ginsenosides, GABA, and Phenolic Compounds.

    Science.gov (United States)

    Lee, Na-Kyoung; Paik, Hyun-Dong

    2017-05-28

    Lactic acid bacteria (LAB) are used as fermentation starters in vegetable and dairy products and influence the pH and flavors of foods. For many centuries, LAB have been used to manufacture fermented foods; therefore, they are generally regarded as safe. LAB produce various substances, such as lactic acid, β-glucosidase, and β-galactosidase, making them useful as fermentation starters. Existing functional substances have been assessed as fermentation substrates for better component bioavailability or other functions. Representative materials that were bioconverted using LAB have been reported and include minor ginsenosides, γ-aminobutyric acid, equol, aglycones, bioactive isoflavones, genistein, and daidzein, among others. Fermentation mainly involves polyphenol and polysaccharide substrates and is conducted using bacterial strains such as Streptococcus thermophilus, Lactobacillus plantarum, and Bifidobacterium sp. In this review, we summarize recent studies of bioconversion using LAB and discuss future directions for this field.

  1. Technologies for the bioconversion of methane into more valuable products.

    Science.gov (United States)

    Cantera, Sara; Muñoz, Raúl; Lebrero, Raquel; López, Juan Carlos; Rodríguez, Yadira; García-Encina, Pedro Antonio

    2018-04-01

    Methane, with a global warming potential twenty five times higher than that of CO 2 is the second most important greenhouse gas emitted nowadays. Its bioconversion into microbial molecules with a high retail value in the industry offers a potential cost-efficient and environmentally friendly solution for mitigating anthropogenic diluted CH 4 -laden streams. Methane bio-refinery for the production of different compounds such as ectoine, feed proteins, biofuels, bioplastics and polysaccharides, apart from new bioproducts characteristic of methanotrophic bacteria, has been recently tested in discontinuous and continuous bioreactors with promising results. This review constitutes a critical discussion about the state-of-the-art of the potential and research niches of biotechnologies applied in a CH 4 biorefinery approach. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Phyto-bioconversion of hard coal in the Cynodon dactylon/coal rhizosphere.

    Science.gov (United States)

    Igbinigie, Eric E; Mutambanengwe, Cecil C Z; Rose, Peter D

    2010-03-01

    Fundamental processes involved in the microbial degradation of coal and its derivatives have been well documented. A mutualistic interaction between plant roots and certain microorganisms to aid growth of plants such as Cynodon dactylon (Bermuda grass) on hard coal dumps has recently been suggested. In the present study coal bioconversion activity of nonmycorrhizal fungi was investigated in the C. dactylon/coal rhizosphere. Fungal growth on 2% Duff-agar, gutation formation on nitric acid treated coal and submerged culture activity in nitrogen-rich and -deficient broth formed part of the screening and selection of the fungi. The selected fungal isolates were confirmed to be found in pristine C. dactylon/coal rhizosphere. To simulate bioconversion, a fungal aliquot of this rhizosphere was used as inoculum for a Perfusate fixed bed bioreactor, packed with coal. The results demonstrate an enhanced coal bioconversion facilitated by low molecular weight organics and the bioconversion of coal may be initiated by an introduction of nitrogen moieties to the coal substrate. These findings suggest a phyto-bioconversion of hard coal involving plant and microbes occurring in the rhizosphere to promote the growth of C. dactylon. An understanding of this relationship can serve as a benchmark for coal dumps rehabilitation as well as for the industrial scale bioprocessing of hard coal.

  3. Integrated bioconversion of syngas into bioethanol and biopolymers.

    Science.gov (United States)

    Lagoa-Costa, Borja; Abubackar, Haris Nalakath; Fernández-Romasanta, María; Kennes, Christian; Veiga, María C

    2017-09-01

    Syngas bioconversion is a promising method for bioethanol production, but some VFA remains at the end of fermentation. A two-stage process was set-up, including syngas fermentation as first stage under strict anaerobic conditions using C. autoethanogenum as inoculum, with syngas (CO/CO 2 /H 2 /N 2 , 30/10/20/40) as gaseous substrate. The second stage consisted in various fed-batch assays using a highly enriched PHA accumulating biomass as inoculum, where the potential for biopolymer production from the remaining acetic acid at the end of the syngas fermentation was evaluated. All of the acetic acid was consumed and accumulated as biopolymer, while ethanol and 2,3-butanediol remained basically unused. It can be concluded that a high C/N ratio in the effluent from the syngas fermentation stage was responsible for non-consumption of alcohols. A maximum PHA content of 24% was reached at the end of the assay. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Energy from refuse by bioconversion, fermentation and residue disposal processes

    Energy Technology Data Exchange (ETDEWEB)

    Pfeffer, J T; Liebman, J C

    1976-01-01

    Bioconversion of organic refuse to CH/sub 4/ by anaerobic fermentation is 1 mechanism by which the energy in urban waste can be reclaimed. Laboratory studies were made to determine the rate and amount of gas production at various operating temperatures. The dewatering characteristics of the spent fermentation slurry were evaluated. The spent solids can be dewatered to a sufficiently low moisture content such that incineration is self-sustaining. The incineration system was evaluated to determine the possible energy recovery from the spent cake. A process for treating the liquid blowdown from the system was developed. A mathematical simulation of the total system was constructed to evaluate performance under various operating conditions. A plant processing 908 tons of refuse/day will produce 3905 m/sup 3/ CH/sub 4//hr. Recovery of just CH/sub 4/ provides a 32.6% efficiency of energy recovery. This efficiency can be increased to 63.4% if steam from the incinerator can be sold.

  5. Analytical Methods for Biomass Characterization during Pretreatment and Bioconversion

    Energy Technology Data Exchange (ETDEWEB)

    Pu, Yunqiao [ORNL; Meng, Xianzhi [University of Tennessee, Knoxville (UTK); Yoo, Chang Geun; Li, Mi; Ragauskas, Arthur J [ORNL

    2016-01-01

    Lignocellulosic biomass has been introduced as a promising resource for alternative fuels and chemicals because of its abundance and complement for petroleum resources. Biomass is a complex biopolymer and its compositional and structural characteristics largely vary depending on its species as well as growth environments. Because of complexity and variety of biomass, understanding its physicochemical characteristics is a key for effective biomass utilization. Characterization of biomass does not only provide critical information of biomass during pretreatment and bioconversion, but also give valuable insights on how to utilize the biomass. For better understanding biomass characteristics, good grasp and proper selection of analytical methods are necessary. This chapter introduces existing analytical approaches that are widely employed for biomass characterization during biomass pretreatment and conversion process. Diverse analytical methods using Fourier transform infrared (FTIR) spectroscopy, gel permeation chromatography (GPC), and nuclear magnetic resonance (NMR) spectroscopy for biomass characterization are reviewed. In addition, biomass accessibility methods by analyzing surface properties of biomass are also summarized in this chapter.

  6. Bioconversion of natural gas to liquid fuel: opportunities and challenges.

    Science.gov (United States)

    Fei, Qiang; Guarnieri, Michael T; Tao, Ling; Laurens, Lieve M L; Dowe, Nancy; Pienkos, Philip T

    2014-01-01

    Natural gas is a mixture of low molecular weight hydrocarbon gases that can be generated from either fossil or anthropogenic resources. Although natural gas is used as a transportation fuel, constraints in storage, relatively low energy content (MJ/L), and delivery have limited widespread adoption. Advanced utilization of natural gas has been explored for biofuel production by microorganisms. In recent years, the aerobic bioconversion of natural gas (or primarily the methane content of natural gas) into liquid fuels (Bio-GTL) by biocatalysts (methanotrophs) has gained increasing attention as a promising alternative for drop-in biofuel production. Methanotrophic bacteria are capable of converting methane into microbial lipids, which can in turn be converted into renewable diesel via a hydrotreating process. In this paper, biodiversity, catalytic properties and key enzymes and pathways of these microbes are summarized. Bioprocess technologies are discussed based upon existing literature, including cultivation conditions, fermentation modes, bioreactor design, and lipid extraction and upgrading. This review also outlines the potential of Bio-GTL using methane as an alternative carbon source as well as the major challenges and future research needs of microbial lipid accumulation derived from methane, key performance index, and techno-economic analysis. An analysis of raw material costs suggests that methane-derived diesel fuel has the potential to be competitive with petroleum-derived diesel. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  7. Challenges and pitfalls of P450-dependent (+)-valencene bioconversion by Saccharomyces cerevisiae.

    Science.gov (United States)

    Gavira, Carole; Höfer, René; Lesot, Agnès; Lambert, Fanny; Zucca, Joseph; Werck-Reichhart, Danièle

    2013-07-01

    Natural nootkatone is a high value ingredient for the flavor and fragrance industry because of its grapefruit flavor/odor, low sensorial threshold and low availability. Valencene conversion into nootkatol and nootkatone is known to be catalyzed by cytochrome P450 enzymes from both prokaryotic and eukaryotic organisms, but so far development of a viable bioconversion process using either native microorganisms or recombinant enzymes was not successful. Using an in silico gene-mining approach, we selected 4 potential candidate P450 enzymes from higher plants and identified two of them that selectively converted (+)-valencene into β-nootkatol with high efficiency when tested using recombinant yeast microsomes in vitro. Recombinant yeast expressing CYP71D51v2 from tobacco and a P450 reductase from arabidopsis was used for optimization of a bioconversion process. Bioconversion assays led to production of β-nootkatol and nootkatone, but with low yields that decreased upon increase of the substrate concentration. The reasons for this low bioconversion efficiency were further investigated and several factors potentially hampering industry-compatible valencene bioconversion were identified. One is the toxicity of the products for yeast at concentrations exceeding 100 mg L⁻¹. The second is the accumulation of β-nootkatol in yeast endomembranes. The third is the inhibition of the CYP71D51v2 hydroxylation reaction by the products. Furthermore, we observed that the formation of nootkatone from β-nootkatol is not P450-dependent but catalyzed by a yeast component. Based on these data, we propose new strategies for implementation of a viable P450-based bioconversion process. Copyright © 2013 Elsevier Inc. All rights reserved.

  8. Bioconversion of lutein by Enterobacter hormaechei to form a new compound, 8-methyl-α-ionone.

    Science.gov (United States)

    Zhong, Guifang; Wang, Fangfang; Sun, Jianhong; Ye, Jianbin; Mao, Duobin; Ma, Ke; Yang, Xuepeng

    2017-07-01

    To investigate the final product of the bioconversion of lutein by a novel lutein-degrading bacterium, Enterobacter hormaechei A20, and the kinetics of the process. A new product, 8-methyl-α-ionone, was resolved by GC-MS. The compound was further identified by NMR. A conversion yield of 90% was achieved by E. hormaechei in 36 h with 10 g lutein l -1 . This is the first report of the bioconversion of lutein to form 8-methyl-α-ionone. A degradation pathway is proposed.

  9. Research priorities in bioconversion of municipal solid waste to produce chemicals, liquid and gaseous fuels

    Energy Technology Data Exchange (ETDEWEB)

    Coombs, J. [BABA Ltd., Reading (United Kingdom)

    1988-09-01

    Areas for future research on the bioconversion of municipal solid wastes are highlighted in order to optimise the potential use of this resource to make chemical, liquid and gaseous fuels. Despite widespread research, a biological understanding of bioconversion technologies, including landfill gas, composting and anaerobic digestion, has yet to be established. Specifically, work on the development and growth of microorganisms in uncontrolled systems and the detailed biochemistry of purified strains needs to be undertaken. The microbial breakdown of xenobiotics to clean up polluted sites, and as an alternative to incineration of toxic organic wastes, is viewed as a desirable outcome of such an understanding. (UK)

  10. Advanced modelling, monitoring, and process control of bioconversion systems

    Science.gov (United States)

    Schmitt, Elliott C.

    Production of fuels and chemicals from lignocellulosic biomass is an increasingly important area of research and industrialization throughout the world. In order to be competitive with fossil-based fuels and chemicals, maintaining cost-effectiveness is critical. Advanced process control (APC) and optimization methods could significantly reduce operating costs in the biorefining industry. Two reasons APC has previously proven challenging to implement for bioprocesses include: lack of suitable online sensor technology of key system components, and strongly nonlinear first principal models required to predict bioconversion behavior. To overcome these challenges batch fermentations with the acetogen Moorella thermoacetica were monitored with Raman spectroscopy for the conversion of real lignocellulosic hydrolysates and a kinetic model for the conversion of synthetic sugars was developed. Raman spectroscopy was shown to be effective in monitoring the fermentation of sugarcane bagasse and sugarcane straw hydrolysate, where univariate models predicted acetate concentrations with a root mean square error of prediction (RMSEP) of 1.9 and 1.0 g L-1 for bagasse and straw, respectively. Multivariate partial least squares (PLS) models were employed to predict acetate, xylose, glucose, and total sugar concentrations for both hydrolysate fermentations. The PLS models were more robust than univariate models, and yielded a percent error of approximately 5% for both sugarcane bagasse and sugarcane straw. In addition, a screening technique was discussed for improving Raman spectra of hydrolysate samples prior to collecting fermentation data. Furthermore, a mechanistic model was developed to predict batch fermentation of synthetic glucose, xylose, and a mixture of the two sugars to acetate. The models accurately described the bioconversion process with an RMSEP of approximately 1 g L-1 for each model and provided insights into how kinetic parameters changed during dual substrate

  11. Xanthobacter sp. C20 contains a novel bioconversion pathway for limonene

    NARCIS (Netherlands)

    Werf, M.J. van der; Keijzer, P.M.; Schaft, P.H. van der

    2000-01-01

    Xanthobacter sp. C20 was isolated from sediment of the river Rhine using cyclohexane as sole source of carbon and energy. Xanthobacter sp. C20 converted both enantiomers of limonene quantitatively into limonene-8,9-epoxide, a not previously described bioconversion product of limonene. With

  12. Multidisciplinary research program directed toward utilization of solar energy through bioconversion of renewable resources. Progress report

    Energy Technology Data Exchange (ETDEWEB)

    Finnerty, W. R.

    1976-07-01

    Progress is reported in four research areas of solar bioconversion. The first program deals with the genetic selection of superior trees, physiological basis of vigor, tissue culture, haploid cell lines, and somatic hybridization. The second deals with the physiology of paraquat-induced oleoresin biogenesis. Separate abstracts were prepared for the other two program areas: biochemical basis of paraquat-induced oleoresin production in pines and biochemistry of methanogenesis. (JSR)

  13. Design of a tailor‐made platform for syngas bioconversion into polyhydroxybutyrate

    OpenAIRE

    Narancic, Tanja; O'Connor, Kevin E.

    2017-01-01

    Summary Biodegradable polymers such as polyhydroxybutyrate (PHB) are part of the emerging portfolio of renewable materials, which are addressing the issue of plastic waste. Syngas, as a cheap, renewable and sustainable resource that can be obtained from biomass or waste, is viewed as an excellent feedstock for different bioprocesses, including syngas to PHB bioconversion. However, due to the hazardous nature of syngas, it is of utmost importance to consider safety aspects of the process. This...

  14. Production of (R)-3-hydroxybutyric acid by fermentation and bioconversion processes with Azohydromonas lata.

    Science.gov (United States)

    Ugwu, Charles U; Tokiwa, Yutaka; Ichiba, Toshio

    2011-06-01

    Feasibility of producing (R)-3-hydroxybutyric acid ((R)-3-HB) using wild type Azohydromonas lata and its mutants (derived by UV mutation) was investigated. A. lata mutant (M5) produced 780 m g/l in the culture broth when sucrose was used as the carbon source. M5 was further studied in terms of its specificity with various bioconversion substrates for production of (R)-3-HB. (R)-3-HB concentration produced in the culture broth by M5 mutant was 2.7-fold higher than that of the wild type strain when sucrose (3% w/v) and (R,S)-1,3-butanediol (3% v/v) were used as carbon source and bioconversion substrate, respectively. Bioconversion of resting cells (M5) with glucose (1% v/w), ethylacetoacetate (2% v/v), and (R,S)-1,3-butanediol (3% v/v), resulted in (R)-3-HB concentrations of 6.5 g/l, 7.3g/l and 8.7 g/l, respectively. Copyright © 2011 Elsevier Ltd. All rights reserved.

  15. Bioconversion of dilute-acid pretreated sorghum bagasse to ethanol by Neurospora crassa

    Energy Technology Data Exchange (ETDEWEB)

    Dogaris, Ioannis; Gkounta, Olga; Mamma, Diomi; Kekos, Dimitris [National Technical Univ. of Athens, Zografou (Greece). Biotechnology Lab.

    2012-07-15

    Bioethanol production from sweet sorghum bagasse (SB), the lignocellulosic solid residue obtained after extraction of sugars from sorghum stalks, can further improve the energy yield of the crop. The aim of the present work was to evaluate a cost-efficient bioconversion of SB to ethanol at high solids loadings (16 % at pretreatment and 8 % at fermentation), low cellulase activities (1-7 FPU/g SB) and co-fermentation of hexoses and pentoses. The fungus Neurospora crassa DSM 1129 was used, which exhibits both depolymerase and co-fermentative ability, as well as mixed cultures with Saccharomyces cerevisiae 2541. A dilute-acid pretreatment (sulfuric acid 2 g/100 g SB; 210 C; 10 min) was implemented, with high hemicellulose decomposition and low inhibitor formation. The bioconversion efficiency of N. crassa was superior to S. cerevisiae, while their mixed cultures had negative effect on ethanol production. Supplementing the in situ produced N. crassa cellulolytic system (1.0 FPU/g SB) with commercial cellulase and {beta}-glucosidase mixture at low activity (6.0 FPU/g SB) increased ethanol production to 27.6 g/l or 84.7 % of theoretical yield (based on SB cellulose and hemicellulose sugar content). The combined dilute-acid pretreatment and bioconversion led to maximum cellulose and hemicellulose hydrolysis 73.3 % and 89.6 %, respectively. (orig.)

  16. Bioconversion of R-(+)-limonene to perillic acid by the yeast Yarrowia lipolytica

    Science.gov (United States)

    Ferrara, Maria Antonieta; Almeida, Débora S.; Siani, Antonio C.; Lucchetti, Leonardo; Lacerda, Paulo S.B.; Freitas, André; Tappin, Marcelo R.R.; Bon, Elba P.S.

    2013-01-01

    Perillyl derivatives are increasingly important due to their flavouring and antimicrobial properties as well as their potential as anticancer agents. These terpenoid species, which are present in limited amounts in plants, may be obtained via bioconversion of selected monoterpene hydrocarbons. In this study, seventeen yeast strains were screened for their ability to oxidize the exocyclic methyl group in the p-menthene moiety of limonene into perillic acid. Of the yeast tested, the highest efficiency was observed for Yarrowia lipolytica ATCC 18942. The conversion of R (+)-limonene by Y. lipolytica was evaluated by varying the pH (3 to 8) and the temperature (25 to 30 °C) in a reaction medium containing 0.5% v/v limonene and 10 g/L of stationary phase cells (dry weight). The best results, corresponding to 564 mg/L of perillic acid, were obtained in buffered medium at pH 7.1 that was incubated at 25 °C for 48 h. The stepwise addition of limonene increased the perillic acid concentration by over 50%, reaching 855 mg/L, whereas the addition of glucose or surfactant to the reaction medium did not improve the bioconversion process. The use of Y. lipolytica showed promise for ease of further downstream processing, as perillic acid was the sole oxidised product of the bioconversion reaction. Moreover, bioprocesses using safe and easy to cultivate yeast cells have been favoured in industry. PMID:24688495

  17. Bioconversion of R-(+-limonene to perillic acid by the yeast Yarrowia lipolytica

    Directory of Open Access Journals (Sweden)

    Maria Antonieta Ferrara

    2013-12-01

    Full Text Available Perillyl derivatives are increasingly important due to their flavouring and antimicrobial properties as well as their potential as anticancer agents. These terpenoid species, which are present in limited amounts in plants, may be obtained via bioconversion of selected monoterpene hydrocarbons. In this study, seventeen yeast strains were screened for their ability to oxidize the exocyclic methyl group in the p-menthene moiety of limonene into perillic acid. Of the yeast tested, the highest efficiency was observed for Yarrowia lipolytica ATCC 18942. The conversion of R (+-limonene by Y. lipolytica was evaluated by varying the pH (3 to 8 and the temperature (25 to 30 ºC in a reaction medium containing 0.5% v/v limonene and 10 gµL of stationary phase cells (dry weight. The best results, corresponding to 564 mgµL of perillic acid, were obtained in buffered medium at pH 7.1 that was incubated at 25 ºC for 48 h. The stepwise addition of limonene increased the perillic acid concentration by over 50%, reaching 855 mgµL, whereas the addition of glucose or surfactant to the reaction medium did not improve the bioconversion process. The use of Y. lipolytica showed promise for ease of further downstream processing, as perillic acid was the sole oxidised product of the bioconversion reaction. Moreover, bioprocesses using safe and easy to cultivate yeast cells have been favoured in industry.

  18. Bioconversion of dilute-acid pretreated sorghum bagasse to ethanol by Neurospora crassa.

    Science.gov (United States)

    Dogaris, Ioannis; Gkounta, Olga; Mamma, Diomi; Kekos, Dimitris

    2012-07-01

    Bioethanol production from sweet sorghum bagasse (SB), the lignocellulosic solid residue obtained after extraction of sugars from sorghum stalks, can further improve the energy yield of the crop. The aim of the present work was to evaluate a cost-efficient bioconversion of SB to ethanol at high solids loadings (16 % at pretreatment and 8 % at fermentation), low cellulase activities (1-7 FPU/g SB) and co-fermentation of hexoses and pentoses. The fungus Neurospora crassa DSM 1129 was used, which exhibits both depolymerase and co-fermentative ability, as well as mixed cultures with Saccharomyces cerevisiae 2541. A dilute-acid pretreatment (sulfuric acid 2 g/100 g SB; 210 °C; 10 min) was implemented, with high hemicellulose decomposition and low inhibitor formation. The bioconversion efficiency of N. crassa was superior to S. cerevisiae, while their mixed cultures had negative effect on ethanol production. Supplementing the in situ produced N. crassa cellulolytic system (1.0 FPU/g SB) with commercial cellulase and β-glucosidase mixture at low activity (6.0 FPU/g SB) increased ethanol production to 27.6 g/l or 84.7 % of theoretical yield (based on SB cellulose and hemicellulose sugar content). The combined dilute-acid pretreatment and bioconversion led to maximum cellulose and hemicellulose hydrolysis 73.3 % and 89.6 %, respectively.

  19. COST-BENEFIT ANALYSIS OF BIOCONVERSION NEUFCHATEL WHEY INTO RECTIFIED ETHANOL AND ORGANIC LIQUID FERTILIZER IN SEMI PILOT SCALE

    Directory of Open Access Journals (Sweden)

    Gemilang Lara UTAMA

    2015-10-01

    Full Text Available Aims of the study was to determine the cost-benefit analysis in neufchatel whey bioconversion into rectified ethanol and organic liquid fertilizer. Bioconversion whey into rectified ethanol and organic liquid fertilizer has shown great potential as a way to reduce the pollution resulting from cheese-making process. Semi pilot scale experiment was done to ferment 5 L neufchatel whey using 5% K. lactis at 33°C for 24 h in semi anaerobic plastic container without agitation and then distilled into 96.2% purity. Data collected and analyzed descriptively related to benefit cost ratio/BCR, net present value/NPV and internal rate returns/IRR. The result showed that semi pilot scale bioconversion of neufchatel whey resulting in 106.42 ml rectified ethanol and 4404.22 ml distillery residue. Economic benefit could achieved by the support of distillery residue sales as organic liquid fertilizer.

  20. Bioconversion of D-psicose to D-tagatose and D-talitol by Mucoraceae fungi.

    Science.gov (United States)

    Yoshihara, Kazutoshi; Shinohara, Yoshihiro; Hirotsu, Takahiro; Izumori, Ken

    2006-03-01

    Rhizopus oryzae MYA-2483, which cannot utilize D-psicose as a sole source of carbon, converted D-psicose to two other compounds. These compounds were identified by NMR and IR as D-tagatose and D-talitol. In this study, we describe for the first time the bioconversion of D-psicose to D-tagatose. Various strains of Mucoraceae fungi, to which R. oryzae MYA-2483 belongs, exhibited conversion activity similar to that of R. oryzae MYA-2483. There is the possibility that a considerable number of fungi belonging to Mucoraceae possess such D-psicose conversion activity.

  1. Xanthobacter sp. C20 contains a novel bioconversion pathway for limonene

    OpenAIRE

    Werf, M.J. van der; Keijzer, P.M.; Schaft, P.H. van der

    2000-01-01

    Xanthobacter sp. C20 was isolated from sediment of the river Rhine using cyclohexane as sole source of carbon and energy. Xanthobacter sp. C20 converted both enantiomers of limonene quantitatively into limonene-8,9-epoxide, a not previously described bioconversion product of limonene. With (4R)-limonene, (4R,8R)-limonene-8,9-epoxide was formed as the only reaction product, while (4S)-limonene was converted into a (78:22) mixture of (4S,8R)- and (4S,8S)-limonene-8,9-epoxide. Cytochrome P-450 w...

  2. Enantioselectivity of the bioconversion of chiral citronellal during the inhibition of wheat seeds germination.

    Science.gov (United States)

    Cavalieri, Andrea; Fischer, Ravit; Larkov, Olga; Dudai, Nativ

    2014-03-01

    Citronellal is one of the most prominent monoterpenes present in many essential oils. Low persistence of essential oils as bioherbicides has often been addressed because of the high volatility of these compounds. Bioconversion of citronellal by wheat seeds releases less aggressive and injurious compounds as demonstrated by their diminished germination. We demonstrated that optically pure citronellal enantiomers were reduced to optically pure citronellol enantiomers with retention of the configuration both in isolated wheat embryos and endosperms. Our findings reveal the potential of essential oils as allelopathic agents providing an insight into their mechanism of action and persistence. Copyright © 2014 Verlag Helvetica Chimica Acta AG, Zürich.

  3. Biofilm reactors for industrial bioconversion processes: employing potential of enhanced reaction rates

    Directory of Open Access Journals (Sweden)

    Karcher Patrick

    2005-08-01

    Full Text Available Abstract This article describes the use of biofilm reactors for the production of various chemicals by fermentation and wastewater treatment. Biofilm formation is a natural process where microbial cells attach to the support (adsorbent or form flocs/aggregates (also called granules without use of chemicals and form thick layers of cells known as "biofilms." As a result of biofilm formation, cell densities in the reactor increase and cell concentrations as high as 74 gL-1 can be achieved. The reactor configurations can be as simple as a batch reactor, continuous stirred tank reactor (CSTR, packed bed reactor (PBR, fluidized bed reactor (FBR, airlift reactor (ALR, upflow anaerobic sludge blanket (UASB reactor, or any other suitable configuration. In UASB granular biofilm particles are used. This article demonstrates that reactor productivities in these reactors have been superior to any other reactor types. This article describes production of ethanol, butanol, lactic acid, acetic acid/vinegar, succinic acid, and fumaric acid in addition to wastewater treatment in the biofilm reactors. As the title suggests, biofilm reactors have high potential to be employed in biotechnology/bioconversion industry for viable economic reasons. In this article, various reactor types have been compared for the above bioconversion processes.

  4. Application of recombinant Pediococcus acidilactici BD16 (fcs +/ech +) for bioconversion of agrowaste to vanillin.

    Science.gov (United States)

    Chakraborty, Debkumar; Selvam, Ammaiyappan; Kaur, Baljinder; Wong, Jonathan Woon Chung; Karthikeyan, Obulisamy Parthiba

    2017-07-01

    Biotechnological production of vanillin is gaining momentum as the natural synthesis of vanillin that is very expensive. Ferulic acid (FA), a costly compound, is used as the substrate to produce vanillin biotechnologically and the making process is still expensive. Therefore, this study investigated the practical use of an agrobiomass waste, rice bran, and provides the first evidence of a cost-effective production of vanillin within 24 h of incubation using recombinant Pediococcus acidilactici BD16 (fcs + /ech + ). Introduction of two genes encoding feruloyl CoA synthetase and enoyl CoA hydratase into the native strain increased vanillin yield to 4.01 g L -1 . Bioconversion was monitored through the transformation of phenolic compounds. A hypothetical metabolic pathway of rice bran during the vanillin bioconversion was proposed with the inserted pathway from ferulic acid to vanillin and compared with that of other metabolic engineered strains. These results could be a gateway of using recombinant lactic acid bacteria for industrial production of vanillin from agricultural waste.

  5. Biofilm reactors for industrial bioconversion processes: employing potential of enhanced reaction rates

    Science.gov (United States)

    Qureshi, Nasib; Annous, Bassam A; Ezeji, Thaddeus C; Karcher, Patrick; Maddox, Ian S

    2005-01-01

    This article describes the use of biofilm reactors for the production of various chemicals by fermentation and wastewater treatment. Biofilm formation is a natural process where microbial cells attach to the support (adsorbent) or form flocs/aggregates (also called granules) without use of chemicals and form thick layers of cells known as "biofilms." As a result of biofilm formation, cell densities in the reactor increase and cell concentrations as high as 74 gL-1 can be achieved. The reactor configurations can be as simple as a batch reactor, continuous stirred tank reactor (CSTR), packed bed reactor (PBR), fluidized bed reactor (FBR), airlift reactor (ALR), upflow anaerobic sludge blanket (UASB) reactor, or any other suitable configuration. In UASB granular biofilm particles are used. This article demonstrates that reactor productivities in these reactors have been superior to any other reactor types. This article describes production of ethanol, butanol, lactic acid, acetic acid/vinegar, succinic acid, and fumaric acid in addition to wastewater treatment in the biofilm reactors. As the title suggests, biofilm reactors have high potential to be employed in biotechnology/bioconversion industry for viable economic reasons. In this article, various reactor types have been compared for the above bioconversion processes. PMID:16122390

  6. Changes in the Anti-Allergic Activities of Sesame by Bioconversion

    Directory of Open Access Journals (Sweden)

    Tae-Dong Jung

    2018-02-01

    Full Text Available Sesame is an important oilseed crop, which has been used as a traditional health food to ameliorate the prevention of various diseases. We evaluated the changes in the anti-allergic activities of sesame by bioconversion. SDS-PAGE of non-fermented sesame proteins showed major allergen bands, while that of fermented sesame showed only a few protein bands. Additionally, we investigated the effectiveness of fermented sesame by bioconversion in tumor necrosis factor-α (TNF-α- and interferon-γ (IFN-γ-induced HaCaT cells. In HaCaT cells, fermented sesame inhibited the mRNA expression of interleukin-6 (IL-6 and interleukin-1β (IL-1β, thymus and macrophage-derived chemokine (MDC/CCL22, activation-regulated chemokine (TARC/CCL17, and intercellular adhesion molecule-1 (ICAM-1. Moreover, fermented sesame inhibited the activation of nuclear factor-κB (NF-κB and signal transducer and activator of transcription 1 (STAT1. Fermented sesame exerts anti-allergic effects by suppressing the expression of chemokines and cytokines via blockade of NF-κB and STAT1 activation.

  7. Biofilm reactors for industrial bioconversion processes: employing potential of enhanced reaction rates.

    Science.gov (United States)

    Qureshi, Nasib; Annous, Bassam A; Ezeji, Thaddeus C; Karcher, Patrick; Maddox, Ian S

    2005-08-25

    This article describes the use of biofilm reactors for the production of various chemicals by fermentation and wastewater treatment. Biofilm formation is a natural process where microbial cells attach to the support (adsorbent) or form flocs/aggregates (also called granules) without use of chemicals and form thick layers of cells known as "biofilms." As a result of biofilm formation, cell densities in the reactor increase and cell concentrations as high as 74 gL(-1) can be achieved. The reactor configurations can be as simple as a batch reactor, continuous stirred tank reactor (CSTR), packed bed reactor (PBR), fluidized bed reactor (FBR), airlift reactor (ALR), upflow anaerobic sludge blanket (UASB) reactor, or any other suitable configuration. In UASB granular biofilm particles are used. This article demonstrates that reactor productivities in these reactors have been superior to any other reactor types. This article describes production of ethanol, butanol, lactic acid, acetic acid/vinegar, succinic acid, and fumaric acid in addition to wastewater treatment in the biofilm reactors. As the title suggests, biofilm reactors have high potential to be employed in biotechnology/bioconversion industry for viable economic reasons. In this article, various reactor types have been compared for the above bioconversion processes.

  8. Characterization of hydrocortisone bioconversion and 16S RNA gene in Synechococcus nidulans cultures.

    Science.gov (United States)

    Rasoul-Amini, S; Ghasemi, Y; Morowvat, M H; Ghoshoon, M B; Raee, M J; Mosavi-Azam, S B; Montazeri-Najafabady, N; Nouri, F; Parvizi, R; Negintaji, N; Khoubani, S

    2010-01-01

    A unicellular cyanobacterium, Synechococcus nidulans (Pringsheim) Komárek, was isolated from paddy-fields and applied in the biotransformation experiment of hydrocortisone (1). This strain has not been previously tested for steroid bioconversion. Fermentation was carried out in BG-11 medium supplemented with 0.05% substrate at 25 degrees C for 14 days of incubation. The obtained products were chromatographically purified followed by their characterization using spectroscopic methods. 11beta,17beta-dihydroxyandrost-4-en-3-one (2), 11beta-hydroxyandrost-4-en-3,17-dione (3), and androst-4-ene-3,17-dione (4) were the main bioproducts in the hydrocortisone bioconversion. The observed bioreaction characteristics were the side chain degradation of the substrate to prepare compounds (2) and (3) following the 11beta-dehydroxylation for accumulation of the compound (4). Time course study showed the accumulation of the product (2) from the second day of the fermentation and compounds (3) and (4) from the third day. All the metabolites reached their maximum concentration in seven days. Cyanobacterial 16S rRNA gene was also amplified by PCR. Sequences were amplified using the universal prokaryotic primers which amplify a approximately 400-bp region of the 16S rRNA gene. PCR products were sequenced to confirm their authenticity as 16S rRNA gene of cyanobacteria. The result of PCR blasted with other sequenced cyanobacteria in NCBI showed 99% identity to the 16S small subunit rRNA of seven Synechococcus species.

  9. Bioconversion of Airborne Methylamine by Immobilized Recombinant Amine Oxidase from the Thermotolerant Yeast Hansenula polymorpha

    Directory of Open Access Journals (Sweden)

    Sasi Sigawi

    2014-01-01

    Full Text Available Aliphatic amines, including methylamine, are air-pollutants, due to their intensive use in industry and the natural degradation of proteins, amino acids, and other nitrogen-containing compounds in biological samples. It is necessary to develop systems for removal of methylamine from the air, since airborne methylamine has a negative effect on human health. The primary amine oxidase (primary amine : oxygen oxidoreductase (deaminating or amine oxidase, AMO; EC 1.4.3.21, a copper-containing enzyme from the thermotolerant yeast Hansenula polymorpha which was overexpressed in baker’s yeast Saccharomyces cerevisiae, was tested for its ability to oxidize airborne methylamine. A continuous fluidized bed bioreactor (CFBR was designed to enable bioconversion of airborne methylamine by AMO immobilized in calcium alginate (CA beads. The results demonstrated that the bioreactor with immobilized AMO eliminates nearly 97% of the airborne methylamine. However, the enzymatic activity of AMO causes formation of formaldehyde. A two-step bioconversion process was therefore proposed. In the first step, airborne methylamine was fed into a CFBR which contained immobilized AMO. In the second step, the gas flow was passed through another CFBR, with alcohol oxidase from the yeast H. polymorpha immobilized in CA, in order to decompose the formaldehyde formed in the first step. The proposed system provided almost total elimination of the airborne methylamine and the formaldehyde.

  10. Microbial community structures in algae cultivation ponds for bioconversion of agricultural wastes from livestock industry for feed production

    Science.gov (United States)

    Dynamics of seasonal microbial community compositions in algae cultivation ponds are complex. There is very limited knowledge on community compositions that may play significant roles in the bioconversion of manure nu¬trients to animal feed. Algae production is an alternative where land area for pro...

  11. [Organic waste treatment by earthworm vermicomposting and larvae bioconversion: review and perspective].

    Science.gov (United States)

    Zhang, Zhi-jian; Liu, Meng; Zhu, Jun

    2013-05-01

    There is a growing attention on the environmental pollution and loss of potential regeneration of resources due to the poor handling of organic wastes, while earthworm vermicomposting and larvae bioconversion are well-known as two promising biotechnologies for sustainable wastes treatments, where earthworms or housefly larvae are employed to convert the organic wastes into humus like material, together with value-added worm product. Taken earthworm ( Eisenia foetida) and housefly larvae ( Musca domestica) as model species, this work illustrates fundamental definition and principle, operational process, technical mechanism, main factors, and bio-chemical features of organisms of these two technologies. Integrated with the physical and biochemical mechanisms, processes of biomass conversion, intestinal digestion, enzyme degradation and microflora decomposition are comprehensively reviewed on waste treatments with purposes of waste reduction, value-addition, and stabilization.

  12. Fibrous Agricultural Biomass as a Potential Source for Bioconversion to Vanillic Acid

    Directory of Open Access Journals (Sweden)

    Pei-Ling Tang

    2014-01-01

    Full Text Available This study was conducted to assess the potential of six fibrous agricultural residues, namely, oil palm empty fruit bunch fiber (OPEFBF, coconut coir fiber (CCF, pineapple peel (PP, pineapple crown leaves (PCL, kenaf bast fiber (KBF, and kenaf core fiber (KCF, as a source of ferulic acid and phenolic compounds for bioconversion into vanillic acid. The raw samples were pretreated with organosolv (NaOH-glycerol and alkaline treatment (NaOH, to produce phenol-rich black liquor. The finding showed that the highest amount of phenolic compounds and ferulic acid was produced from CCF and PP, respectively. This study also found that organosolv treatment was the superior method for phenolic compound extraction, whereas alkaline treatment was the selective method for lignin extraction. Vanillic acid production by Aspergillus niger I-1472 was only observed when the fermentation broth was fed with liquors from PP and PCL, possibly due to the higher levels of ferulic acid in those samples.

  13. Optimising the anaerobic co-digestion of urban organic waste using dynamic bioconversion mathematical modelling

    DEFF Research Database (Denmark)

    Fitamo, Temesgen Mathewos; Boldrin, Alessio; Dorini, G.

    2016-01-01

    Mathematical anaerobic bioconversion models are often used as a convenient way to simulate the conversion of organic materials to biogas. The aim of the study was to apply a mathematical model for simulating the anaerobic co-digestion of various types of urban organic waste, in order to develop...... in a continuously stirred tank reactor. The model's outputs were validated with experimental results obtained in thermophilic conditions, with mixed sludge as a single substrate and urban organic waste as a co-substrate at hydraulic retention times of 30, 20, 15 and 10 days. The predicted performance parameter...... (methane productivity and yield) and operational parameter (concentration of ammonia and volatile fatty acid) values were reasonable and displayed good correlation and accuracy. The model was later applied to identify optimal scenarios for an urban organic waste co-digestion process. The simulation...

  14. An alternative approach to the bioconversion of sweet sorghum carbohydrates to ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Mamma, D.; Christakopoulos, P.; Koullas, D.; Kekos, D.; Macris, B.J.; Koukios, E. [National Technical Univ. of Athens (Greece). Dept. of Chemical Engineering

    1995-10-01

    The ethanol fermentation of juice and press case, resulting from the squeezing of sweet sorghum stalks at high pressure was investigated. The juice was fermented by Saccharomyces cerevisiae and yielded 4.8 g ethanol per 100 g of fresh stalks. The press cake was fermented directly to ethanol by a mixed culture of Fusarium oxysporum and Saccharomyces cerevisiae and yielded 5.1 g ethanol per 100 g of fresh stalks. An overall ethanol concentration and yield of 5.6% (w/v) and 9.9 g of ethanol per 100 g of fresh stalks respectively was obtained. Based on soluble carbohydrates, the ethanol yield from press cake was doubled while the overall theoretical yield was enhanced by 20.7% due to the bioconversion of a significant portion of cell wall polysaccharides to ethanol. The process was found promising for further investigation. (Author)

  15. Bioconversion of (+)-valencene in submerged cultures of the ascomycete Chaetomium globosum.

    Science.gov (United States)

    Kaspera, Rüdiger; Krings, Ulrich; Nanzad, Tsevegsuren; Berger, Ralf G

    2005-06-01

    Submerged cultures of the ascomycete Chaetomium globosum oxidised the exogenous sesquiterpene (+)-valencene to nootkatone via the stereoselective generation of alpha-nootkatol. Inhibition experiments suggested that the first introduction of oxygen, the rate-limiting step of the bioconversion, may have been catalysed by a cytochrome-P450-monooxygenase. However, nootkatone was not the final metabolite: further flavour-active and inactive, non-volatile oxidation products were identified. (+)-Valencene and the flavour-active mono-oxyfunctionalised transformation products, alpha-nootkatol, nootkatone, and valencene-11,12-epoxide accumulated preferably inside the fungal cells. Di- and poly-oxygenated products, such as nootkatone-11,12-epoxide, were found solely in the culture medium, indicating an active transport of these metabolites into the extracellular compartment during (+)-valencene detoxification. These metabolic properties may have contributed to the high tolerance of the fungus towards the exogenous hydrocarbon.

  16. A novel process for enhancing oil production in algae biorefineries through bioconversion of solid by-products.

    Science.gov (United States)

    Trzcinski, Antoine P; Hernandez, Ernesto; Webb, Colin

    2012-07-01

    This paper focuses on a novel process for adding value to algae residue. In current processes oleaginous microalgae are grown and harvested for lipid production leaving a lipid-free algae residue. The process described here includes conversion of the carbohydrate fraction into glucose prior to lipid extraction. This can be fermented to produce up to 15% additional lipids using another oleaginous microorganism. It was found that in situ enzymes can hydrolyze storage carbohydrates in the algae into glucose and that a temperature of 55 °C for about 20 h gave the best glucose yield. Up to 75% of available carbohydrates were converted to a generic fermentation feedstock containing 73 g/L glucose. The bioconversion step was found to increase the free water content by 60% and it was found that when the bioconversion was carried out prior to the extraction step, it improved the solvent extractability of lipids from the algae. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. An efficient approach to bioconversion kinetic model generation based on automated microscale experimentation integrated with model driven experimental design

    DEFF Research Database (Denmark)

    Chen, B. H.; Micheletti, M.; Baganz, F.

    2009-01-01

    -erythrulose. Experiments were performed using automated microwell studies at the 150 or 800 mu L scale. The derived kinetic parameters were then verified in a second round of experiments where model predictions showed excellent agreement with experimental data obtained under conditions not included in the original......Reliable models of enzyme kinetics are required for the effective design of bioconversion processes. Kinetic expressions of the enzyme-catalysed reaction rate however, are frequently complex and establishing accurate values of kinetic parameters normally requires a large number of experiments....... These can be both time consuming and expensive when working with the types of non-natural chiral intermediates important in pharmaceutical syntheses. This paper presents ail automated microscale approach to the rapid and cost effective generation of reliable kinetic models useful for bioconversion process...

  18. Comparative study of the bioconversion process using R-(+)- and S-(-)-limonene as substrates for Fusarium oxysporum 152B.

    Science.gov (United States)

    Molina, Gustavo; Bution, Murillo L; Bicas, Juliano L; Dolder, Mary Anne Heidi; Pastore, Gláucia M

    2015-05-01

    This study compared the bioconversion process of S-(-)-limonene into limonene-1,2-diol with the already established biotransformation of R-(+)-limonene into α-terpineol using the same biocatalyst in both processes, Fusarium oxysporum 152B. The bioconversion of the S-(-)-isomer was tested on cell permeabilisation under anaerobic conditions and using a biphasic system. When submitted to permeabilisation trials, this biocatalyst has shown a relatively high resistance; still, no production of limonene-1,2-diol and a loss of activity of the biocatalyst were observed after intense cell treatment, indicating a complete loss of cell viability. Furthermore, the results showed that this process can be characterised as an aerobic system that was catalysed by limonene-1,2-epoxide hydrolase, had an intracellular nature and was cofactor-dependent because the final product was not detected by an anaerobic process. Finally, this is the first report to characterise the bioconversion of R-(+)- and S-(-)-limonene by cellular detoxification using ultra-structural analysis. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Combinatorial pretreatment and fermentation optimization enabled a record yield on lignin bioconversion.

    Science.gov (United States)

    Liu, Zhi-Hua; Xie, Shangxian; Lin, Furong; Jin, Mingjie; Yuan, Joshua S

    2018-01-01

    Lignin valorization has recently been considered to be an essential process for sustainable and cost-effective biorefineries. Lignin represents a potential new feedstock for value-added products. Oleaginous bacteria such as Rhodococcus opacus can produce intracellular lipids from biodegradation of aromatic substrates. These lipids can be used for biofuel production, which can potentially replace petroleum-derived chemicals. However, the low reactivity of lignin produced from pretreatment and the underdeveloped fermentation technology hindered lignin bioconversion to lipids. In this study, combinatorial pretreatment with an optimized fermentation strategy was evaluated to improve lignin valorization into lipids using R. opacus PD630. As opposed to single pretreatment, combinatorial pretreatment produced a 12.8-75.6% higher lipid concentration in fermentation using lignin as the carbon source. Gas chromatography-mass spectrometry analysis showed that combinatorial pretreatment released more aromatic monomers, which could be more readily utilized by lignin-degrading strains. Three detoxification strategies were used to remove potential inhibitors produced from pretreatment. After heating detoxification of the lignin stream, the lipid concentration further increased by 2.9-9.7%. Different fermentation strategies were evaluated in scale-up lipid fermentation using a 2.0-l fermenter. With laccase treatment of the lignin stream produced from combinatorial pretreatment, the highest cell dry weight and lipid concentration were 10.1 and 1.83 g/l, respectively, in fed-batch fermentation, with a total soluble substrate concentration of 40 g/l. The improvement of the lipid fermentation performance may have resulted from lignin depolymerization by the combinatorial pretreatment and laccase treatment, reduced inhibition effects by fed-batch fermentation, adequate oxygen supply, and an accurate pH control in the fermenter. Overall, these results demonstrate that combinatorial

  20. Engineering Ligninolytic Consortium for Bioconversion of Lignocelluloses to Ethanol and Chemicals.

    Science.gov (United States)

    Bilal, Muhammad; Nawaz, Muhammad Zohaib; Iqbal, Hafiz M N; Hou, Jialin; Mahboob, Shahid; Al-Ghanim, Khalid A; Cheng, Hairong

    2018-01-01

    Rising environmental concerns and recent global scenario of cleaner production and consumption are leading to the design of green industrial processes to produce alternative fuels and chemicals. Although bioethanol is one of the most promising and eco-friendly alternatives to fossil fuels yet its production from food and feed has received much negative criticism. The main objective of this study was to present the noteworthy potentialities of lignocellulosic biomass as an enormous and renewable biological resource. The particular focus was also given on engineering ligninolytic consortium for bioconversion of lignocelluloses to ethanol and chemicals on sustainable and environmentally basis. Herein, an effort has been made to extensively review, analyze and compile salient information related to the topic of interest. Several authentic bibliographic databases including PubMed, Scopus, Elsevier, Springer, Bentham Science and other scientific databases were searched with utmost care, and inclusion/ exclusion criterion was adopted to appraise the quality of retrieved peer-reviewed research literature. Bioethanol production from lignocellulosic biomass can largely satisfy the possible inconsistency of first-generation ethanol since it utilizes inedible lignocellulosic feedstocks, primarily sourced from agriculture and forestry wastes. Two major polysaccharides in lignocellulosic biomass namely, cellulose and hemicellulose constitute a complex lignocellulosic network by connecting with lignin, which is highly recalcitrant to depolymerization. Several attempts have been made to reduce the cost involved in the process through improving the pretreatment process. While, the ligninolytic enzymes of white rot fungi (WRF) including laccase, lignin peroxidase (LiP), and manganese peroxidase (MnP) have appeared as versatile biocatalysts for delignification of several lignocellulosic residues. The first part of the review is mainly focused on engineering ligninolytic consortium

  1. Hydrocarbon bio-jet fuel from bioconversion of poplar biomass: life cycle assessment.

    Science.gov (United States)

    Budsberg, Erik; Crawford, Jordan T; Morgan, Hannah; Chin, Wei Shan; Bura, Renata; Gustafson, Rick

    2016-01-01

    Bio-jet fuels compatible with current aviation infrastructure are needed as an alternative to petroleum-based jet fuel to lower greenhouse gas emissions and reduce dependence on fossil fuels. Cradle to grave life cycle analysis is used to investigate the global warming potential and fossil fuel use of converting poplar biomass to drop-in bio-jet fuel via a novel bioconversion platform. Unique to the biorefinery designs in this research is an acetogen fermentation step. Following dilute acid pretreatment and enzymatic hydrolysis, poplar biomass is fermented to acetic acid and then distilled, hydroprocessed, and oligomerized to jet fuel. Natural gas steam reforming and lignin gasification are proposed to meet hydrogen demands at the biorefineries. Separate well to wake simulations are performed using the hydrogen production processes to obtain life cycle data. Both biorefinery designs are assessed using natural gas and hog fuel to meet excess heat demands. Global warming potential of the natural gas steam reforming and lignin gasification bio-jet fuel scenarios range from CO2 equivalences of 60 to 66 and 32 to 73 g MJ(-1), respectively. Fossil fuel usage of the natural gas steam reforming and lignin gasification bio-jet fuel scenarios range from 0.78 to 0.84 and 0.71 to 1.0 MJ MJ(-1), respectively. Lower values for each impact category result from using hog fuel to meet excess heat/steam demands. Higher values result from using natural gas to meet the excess heat demands. Bio-jet fuels produced from the bioconversion of poplar biomass reduce the global warming potential and fossil fuel use compared with petroleum-based jet fuel. Production of hydrogen is identified as a major source of greenhouse gas emissions and fossil fuel use in both the natural gas steam reforming and lignin gasification bio-jet simulations. Using hog fuel instead of natural gas to meet heat demands can help lower the global warming potential and fossil fuel use at the biorefineries.

  2. Improvement in irradiation pasteurization on sugarcane bagasse for its fungal bioconversion to animal feed

    International Nuclear Information System (INIS)

    Nguyen Duy Lam

    2002-01-01

    Goals of this study were to reduce radiation dose required for bagase pasteurization and to convert the pasteurized bagasse into animal feed by using fungal fermentation. Comparative study on the effectiveness of radiation decontamination on moisturized and dried bagasse showed different doses required for pasteurization. Radiation treatment on wetted substratum bags required 20 kGy, while dried bagasse needed only 10 kGy for pasteurization. In comparison with wetted bagasse substratum, the pasteurized dry bagasse has more dominant advantages because it can be kept for storage, transportation and distribution to household producers. Moisturizing substratum with tap water can be done just before inoculation with mycelial seed. Bioconversion of sugarcane bagasse to ruminant feed by using fungal fermentation was investigated. The in sacco digestibility of fermented substratum increased with incubation period and it was higher than that of paddy rice straw and comparable to Pangola grass after 35 days of fermentation. As the digestibility of mushroom-harvested residue was still higher than that of non-fermented bagasse, the fermentation by using Pleurotus spp. could simultaneously provide edible mushroom and animal feed as well. (Author)

  3. Bioconversion of D-galactose into D-tagatose by expression of L-arabinose isomerase.

    Science.gov (United States)

    Roh, H J; Kim, P; Park, Y C; Choi, J H

    2000-02-01

    D-Tagatose is a potential bulking agent in food as a non-calorific sweetener. To produce D-tagatose from cheaper resources, plasmids harbouring the L-arabinose isomerase gene (araA) from Escherichia coli, Bacillus subtilis and Salmonella typhimurium were constructed because L-arabinose isomerase was suggested previously as an enzyme that mediates the bioconversion of galactose into tagatose as well as that of arabinose to ribulose. The constructed plasmids were named pTC101, pTC105 and pTC106, containing araA from E. coli, B. subtilis and S. typhimurium respectively. In the cultures of recombinant E. coli with pTC101, pTC105 and pTC106, tagatose was produced from galactose in 9.9, 7.1 and 6.9% yields respectively. The enzyme extract of E. coli with the plasmid pTC101 also converted galactose into tagatose with a 96.4% yield.

  4. Direct bioconversion of brown algae into ethanol by thermophilic bacterium Defluviitalea phaphyphila.

    Science.gov (United States)

    Ji, Shi-Qi; Wang, Bing; Lu, Ming; Li, Fu-Li

    2016-01-01

    Brown algae are promising feedstocks for biofuel production with inherent advantages of no structural lignin, high growth rate, and no competition for land and fresh water. However, it is difficult for one microorganism to convert all components of brown algae with different oxidoreduction potentials to ethanol. Defluviitalea phaphyphila Alg1 is the first characterized thermophilic bacterium capable of direct utilization of brown algae. Defluviitalea phaphyphila Alg1 can simultaneously utilize mannitol, glucose, and alginate to produce ethanol, and high ethanol yields of 0.47 g/g-mannitol, 0.44 g/g-glucose, and 0.3 g/g-alginate were obtained. A rational redox balance system under obligate anaerobic condition in fermenting brown algae was revealed in D. phaphyphila Alg1 through genome and redox analysis. The excess reducing equivalents produced from mannitol metabolism were equilibrated by oxidizing forces from alginate assimilation. Furthermore, D. phaphyphila Alg1 can directly utilize unpretreated kelp powder, and 10 g/L of ethanol was accumulated within 72 h with an ethanol yield of 0.25 g/g-kelp. Microscopic observation further demonstrated the deconstruction process of brown algae cell by D. phaphyphila Alg1. The integrated biomass deconstruction system of D. phaphyphila Alg1, as well as its high ethanol yield, provided us an excellent alternative for brown algae bioconversion at elevated temperature.

  5. Glucose bioconversion profile in the syngas-metabolizing species Clostridium carboxidivorans.

    Science.gov (United States)

    Fernández-Naveira, Ánxela; Veiga, María C; Kennes, Christian

    2017-11-01

    Some clostridia produce alcohols (ethanol, butanol, hexanol) from gases (CO, CO 2 , H 2 ) and others from carbohydrates (e.g., glucose). C. carboxidivorans can metabolize both gases as well as glucose. However, its bioconversion profile on glucose had not been reported. It was observed that C. carboxidivorans does not follow a typical solventogenic stage when grown on glucose. Indeed, at pH 6.2, it produced first a broad range of acids (acetic, butyric, hexanoic, formic, and lactic acids), several of which are generally not found, under similar conditions, during gas fermentation. Medium acidification did not allow the conversion of fatty acids into solvents. Production of some alcohols from glucose was observed in C. carboxidivorans but at high pH rather than under acidic conditions, and the total concentration of those solvents was low. At high pH, formic acid was produced first and later converted to acetic acid, but organic acids were not metabolized at low pH. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Novel Magnetic Cross-Linked Cellulase Aggregates with a Potential Application in Lignocellulosic Biomass Bioconversion

    Directory of Open Access Journals (Sweden)

    Junqi Jia

    2017-02-01

    Full Text Available The utilization of renewable biomass resources to produce high-value chemicals by enzymatic processes is beneficial for alternative energy production, due to the accelerating depletion of fossil fuels. As immobilization techniques can improve enzyme stability and reusability, a novel magnetic cross-linked cellulase aggregate has been developed and applied for biomass bioconversion. The crosslinked aggregates could purify and immobilize enzymes in a single operation, and could then be combined with magnetic nanoparticles (MNPs, which provides easy separation of the materials. The immobilized cellulase showed a better activity at a wider temperature range and pH values than that of the free cellulase. After six cycles of consecutive reuse, the immobilized cellulase performed successful magnetic separation and retained 74% of its initial activity when carboxylmethyl cellulose (CMC was used as the model substrate. Furthermore, the structure and morphology of the immobilized cellulase were studied by Fourier transform infrared spectroscopy (FTIR and scanning electron microscopy (SEM. Moreover, the immobilized cellulase was shown to hydrolyze bamboo biomass with a yield of 21%, and was re-used in biomass conversion up to four cycles with 38% activity retention, which indicated that the immobilized enzyme has good potential for biomass applications.

  7. Novel Magnetic Cross-Linked Cellulase Aggregates with a Potential Application in Lignocellulosic Biomass Bioconversion.

    Science.gov (United States)

    Jia, Junqi; Zhang, Weiwei; Yang, Zengjie; Yang, Xianling; Wang, Na; Yu, Xiaoqi

    2017-02-10

    The utilization of renewable biomass resources to produce high-value chemicals by enzymatic processes is beneficial for alternative energy production, due to the accelerating depletion of fossil fuels. As immobilization techniques can improve enzyme stability and reusability, a novel magnetic cross-linked cellulase aggregate has been developed and applied for biomass bioconversion. The crosslinked aggregates could purify and immobilize enzymes in a single operation, and could then be combined with magnetic nanoparticles (MNPs), which provides easy separation of the materials. The immobilized cellulase showed a better activity at a wider temperature range and pH values than that of the free cellulase. After six cycles of consecutive reuse, the immobilized cellulase performed successful magnetic separation and retained 74% of its initial activity when carboxylmethyl cellulose (CMC) was used as the model substrate. Furthermore, the structure and morphology of the immobilized cellulase were studied by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). Moreover, the immobilized cellulase was shown to hydrolyze bamboo biomass with a yield of 21%, and was re-used in biomass conversion up to four cycles with 38% activity retention, which indicated that the immobilized enzyme has good potential for biomass applications.

  8. Bioconversion of fish solid waste into PHB using Bacillus subtilis based submerged fermentation process.

    Science.gov (United States)

    Mohapatra, S; Sarkar, B; Samantaray, D P; Daware, A; Maity, S; Pattnaik, S; Bhattacharjee, S

    2017-12-01

    Currently, one of the major problem affecting the world is solid waste management, predominantly petroleum-based plastic and fish solid waste (FSW). However, it is very difficult to reduce the consumption of plastic as well as fish products, but it is promising to convert FSW to biopolymer to reduce eco-pollution. On account of that, the bioconversion of FSW extract to polyhydroxybutyrate (PHB) was undertaken by using Bacillus subtilis (KP172548). Under optimized conditions, 1.62 g/L of PHB has been produced by the bacterium. The purified compound was further characterized by advanced analytical technologies to elucidate its chemical structure. Results indicated that the biopolymer was found to be PHB, the most common homopolymer of polyhydroxyalkanoates (PHAs). This is the first report demonstrating the efficacy of B. subtilis to utilize FSW extract to produce biopolymer. The biocompatibility of the PHB against murine macrophage cell line RAW264.7 demonstrated that, it was comparatively less toxic, favourable for surface attachment and proliferation in comparison with poly-lactic acid (PLA) and commercially available PHB. Thus, further exploration is highly indispensable to use FSW extract as a substrate for production of PHB at pilot scale.

  9. Physiological and Chemical Studies on the Bioconversion of Glycyrrhizin by Aspergillus niger NRRL595

    Directory of Open Access Journals (Sweden)

    El-Refai, A. M. H.

    2012-06-01

    Full Text Available Glycyrrhizin (GL, the well-known sweet saponin of licorice, has been used as a food-additive and as a medicine. Its aglycone, glycyrrhetic acid (GA showed antiinflamatory, antiulcer and antiviral properties. GA is now produced form GL by acid hydrolysis. However, it is difficult to obtain GA in a good yield by using this method, because many by-productsare also produced. Screening of different microorganisms (13 bacteria, 2 yeasts and 23 fungi for production of GA from GL revealed that Aspergillus niger NRRL 595 produced the highest yield of GA. The bioconversion of GL by A. niger NRRL 595 for 96 h, followed by isolation and purification of the transformation products led to the separation of two conversion products, namely: GA and 3-oxo-GA. Confirmation of the identity of these products was established by determination of their Rf values, m.p., and IR, UV, MS and NMR spectra. The conditions for cultivation of this fungus with the maximum hydrolytic activity for the maximum yield of GA were investigated. Based on the results, A. niger NRRL 595 was cultivated with a medium composed of 1.75 % GL, 0.5 % glucose, 0.8 % corn steep liquor at pH 6.5 at 32 °C for 96 h. The cultivation of fungal cells under the latter conditions afforded GA and 3-oxo-GA in a yield of 65 % and 22 %, respectively.

  10. Assessing the environmental sustainability of early stage design for bioprocesses under uncertainties: An analysis of glycerol bioconversion

    DEFF Research Database (Denmark)

    Loureiro da Costa Lira Gargalo, Carina; Cheali, Peam; Posada, John A.

    2016-01-01

    The development of a bio-based economy is seen as a key strategy towards a sustainable society in a world facing climate change, energy security and social distress. However, since substantial uncertainty is involved in early-stage design analyses, the ranking and identification of potential......; and lastly, (v) rank the alternatives within the design space. Finally, the methodology's applicability is highlighted by screening early-stage glycerol bioconversion routes to value-added chemicals for future biorefinery concepts. Through the proposed methodology, it was demonstrated that the statistical...

  11. Growth, bioconversion of isoflavones and probiotic properties of parent and subsequent passages of Lactobacillus upon ultraviolet radiation.

    Science.gov (United States)

    Yeo, Siok-Koon; Liong, Min-Tze

    2012-11-01

    The objective of this study was to evaluate the effects of ultraviolet (UV) radiation (UVB; 90 J/m²) on growth, bioconversion of isoflavones and probiotic properties of parent and subsequent passages of L. casei FTDC 2113. UV radiation significantly enhanced (P radiation also promoted (P radiation were only prevalent in the parent cells without inheritance by first, second and third passage of cells. Although temporary, our results suggested that UV radiation could enhance the bioactive and probiotic potentials of L. casei FTDC 2113, and thus could be applied for the production of probiotic products with enhanced bioactivity.

  12. Bioconversion of isoeugenol to vanillin and vanillic acid using the resting cells of Trichosporon asahii.

    Science.gov (United States)

    Ashengroph, Morahem; Amini, Jahanshir

    2017-12-01

    40 isoeugenol-tolerant yeasts were isolated from the rhizosphere soil samples which in turn were collected from aromatic plants in different regions of Iran, and further tested for their ability to grow on a minimal medium containing isoeugenol as the sole carbon and energy source. Nine isolates which were able to grow on isoeugenol were examined for their ability to convert isoeugenol into vanillin under growing cell experiments. Of the tested yeasts, the highest conversion efficiency was observed in isolate MP24. The isolate was identified as Trichosporon asahii based on morphological, biochemical and molecular (ITS region) characters and tested to effectively convert isoeugenol into vanillin under resting cell system. A comparative analysis of thin layer chromatography (TLC), UV-Vis spectrometry, and high-performance liquid chromatography (HPLC) verified that vanillin and vanillic acid are accumulated as two major metabolites using T. asahii strain MP24 resting cells. In the presence of 7.5 g/l of wet weight cells of the strain MP24 pre-grown on isoeugenol and harvested at the end of the exponential growth phase, the optimal concentration of vanillin reached 2.4 g/l with a molar conversion of 52.5% in the potassium phosphate buffer (100 mM, pH 5.8) supplemented with 5 g/l of isoeugenol and 2% (v/v) N , N -dimethylformamide (DMF). The total concentration of vanillin and vanillic acid obtained from the bioconversion process was 4.2 g/l (total molar yield of 88.3%). Until now, no data has been published on the conversion of isoeugenol into vanillin by the strains of the genus Trichosporon .

  13. Bioconversion of Radiation Processed Dried Tomato Pomace to High Protein Animal Fee

    International Nuclear Information System (INIS)

    Farag, H.; Diaa El-Din, M.; El-Niely, H. F.G.

    2006-01-01

    The increasing expansion of agro-industrial activity over the last 50 years has led to the accumulation of a large quantity of organic residues all over the world that they have become a threat to the environment. Bioconversion of these wastes seems to be a practical and promising alternative for increasing their nutritional value, transforming them into animal feed and thus producing a value added product. Radiation processing has the capability to reduce or eliminate pathogenic bacteria, insects and parasites, thereby increasing the utilization and sustainable management of waste organic matter from food production and processing while contributing to improve food quality and reducing the environmental impact of the wastes. The main purpose of this study was to evaluate the effect of radiation treatment at 25 kGy and fermentation process by Aspergillus niger, on crude and soluble protein, amino acid profile, available lysine and in vitro digestibility of dried tomato pomace (DTP), the by-product of the tomato canning industry. The study has also, investigated the effect of supplementation of 30% of raw or processed DTP meal in food of male Albino rats for six weeks on body and liver weight evaluation and the effect on blood lipid pattern. The work concluded that the combination between the irradiation of DTP at 25 kGy and fermentation process has increased the nutritional value of treated DTP meal and improved the plasma and liver lipid pattern of rats. Therefore, the combination treatment has beneficial effects on recycling of DTP and permits it to be included in monogastric animals' food without any health hazard or nutritional problem

  14. Metabolic responses in Candida tropicalis to complex inhibitors during xylitol bioconversion.

    Science.gov (United States)

    Wang, Shizeng; Li, Hao; Fan, Xiaoguang; Zhang, Jingkun; Tang, Pingwah; Yuan, Qipeng

    2015-09-01

    During xylitol fermentation, Candida tropicalis is often inhibited by inhibitors in hemicellulose hydrolysate. The mechanisms involved in the metabolic responses to inhibitor stress and the resistances to inhibitors are still not clear. To understand the inhibition mechanisms and the metabolic responses to inhibitors, a GC/MS-based metabolomics approach was performed on C. tropicalis treated with and without complex inhibitors (CI, including furfural, phenol and acetic acid). Partial least squares discriminant analysis was used to determine the metabolic variability between CI-treated groups and control groups, and 25 metabolites were identified as possible entities responsible for the discrimination caused by inhibitors. We found that xylose uptake rate and xylitol oxidation rate were promoted by CI treatment. Metabolomics analysis showed that the flux from xylulose to pentose phosphate pathway increased, and tricarboxylic acid cycle was disturbed by CI. Moreover, the changes in levels of 1,3-propanediol, trehalose, saturated fatty acids and amino acids showed different mechanisms involved in metabolic responses to inhibitor stress. The increase of 1,3-propanediol was considered to be correlated with regulating redox balance and osmoregulation. The increase of trehalose might play a role in protein stabilization and cellular membranes protection. Saturated fatty acids could cause the decrease of membrane fluidity and make the plasma membrane rigid to maintain the integrity of plasma membrane. The deeper understanding of the inhibition mechanisms and the metabolic responses to inhibitors will provide us with more information on the metabolism regulation during xylitol bioconversion and the construction of industrial strains with inhibitor tolerance for better utilization of bioresource. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. The prospects of cellulase-producing bacteria for the bioconversion of lignocellulosic biomass.

    Science.gov (United States)

    Maki, Miranda; Leung, Kam Tin; Qin, Wensheng

    2009-07-29

    Lignocellulosic biomass is a renewable and abundant resource with great potential for bioconversion to value-added bioproducts. However, the biorefining process remains economically unfeasible due to a lack of biocatalysts that can overcome costly hurdles such as cooling from high temperature, pumping of oxygen/stirring, and, neutralization from acidic or basic pH. The extreme environmental resistance of bacteria permits screening and isolation of novel cellulases to help overcome these challenges. Rapid, efficient cellulase screening techniques, using cellulase assays and metagenomic libraries, are a must. Rare cellulases with activities on soluble and crystalline cellulose have been isolated from strains of Paenibacillus and Bacillus and shown to have high thermostability and/or activity over a wide pH spectrum. While novel cellulases from strains like Cellulomonas flavigena and Terendinibacter turnerae, produce multifunctional cellulases with broader substrate utilization. These enzymes offer a framework for enhancement of cellulases including: specific activity, thermalstability, or end-product inhibition. In addition, anaerobic bacteria like the clostridia offer potential due to species capable of producing compound multienzyme complexes called cellulosomes. Cellulosomes provide synergy and close proximity of enzymes to substrate, increasing activity towards crystalline cellulose. This has lead to the construction of designer cellulosomes enhanced for specific substrate activity. Furthermore, cellulosome-producing Clostridium thermocellum and its ability to ferment sugars to ethanol; its amenability to co-culture and, recent advances in genetic engineering, offer a promising future in biofuels. The exploitation of bacteria in the search for improved enzymes or strategies provides a means to upgrade feasibility for lignocellulosic biomass conversion, ultimately providing means to a 'greener' technology.

  16. In vitro bioconversion of chitin to pyruvate with thermophilic enzymes.

    Science.gov (United States)

    Honda, Kohsuke; Kimura, Keisuke; Ninh, Pham Huynh; Taniguchi, Hironori; Okano, Kenji; Ohtake, Hisao

    2017-09-01

    Chitin is the second most abundant organic compound on the planet and thus has been regarded as an alternative resource to petroleum feedstocks. One of the key challenges in the biological conversion of biomass-derived polysaccharides, such as cellulose and chitin, is to close the gap between optimum temperatures for enzymatic saccharification and microbial fermentation and to implement them in a single bioreactor. To address this issue, in the present study, we aimed to perform an in vitro, one-pot bioconversion of chitin to pyruvate, which is a precursor of a wide range of useful metabolites. Twelve thermophilic enzymes, including that for NAD + regeneration, were heterologously produced in Escherichia coli and semi-purified by heat treatment of the crude extract of recombinant cells. When the experimentally decided concentrations of enzymes were incubated with 0.5 mg mL -1 colloidal chitin (equivalent to 2.5 mM N-acetylglucosamine unit) and an adequate set of cofactors at 70°C, 0.62 mM pyruvate was produced in 5 h. Despite the use of a cofactor-balanced pathway, determination of the pool sizes of cofactors showed a rapid decrease in ATP concentration, most probably due to the thermally stable ATP-degrading enzyme(s) derived from the host cell. Integration of an additional enzyme set of thermophilic adenylate kinase and polyphosphate kinase led to the deceleration of ATP degradation, and the final product titer was improved to 2.1 mM. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  17. Directed evolution of toluene dioxygenase from Pseudomonas putida for improved selectivity toward cis-indandiol during indene bioconversion.

    Science.gov (United States)

    Zhang, N; Stewart, B G; Moore, J C; Greasham, R L; Robinson, D K; Buckland, B C; Lee, C

    2000-10-01

    Toluene dioxygenase (TDO) from Pseudomonas putida F1 converts indene to a mixture of cis-indandiol (racemic), 1-indenol, and 1-indanone. The desired product, cis-(1S,2R)-indandiol, is a potential key intermediate in the chemical synthesis of indinavir sulfate (Crixivan), Merck's HIV-1 protease inhibitor for the treatment of AIDS. To reduce the undesirable byproducts 1-indenol and 1-indanone formed during indene bioconversion, the recombinant TDO expressed in Escherichia coli was evolved by directed evolution using the error-prone polymerase chain reaction (epPCR) method. High-throughput fluorometric and spectrophotometric assays were developed for rapid screening of the mutant libraries in a 96-well format. Mutants with reduced 1-indenol by-product formation were identified, and the individual indene bioconversion product profiles of the selected mutants were confirmed by HPLC. Changes in the amino acid sequence of the mutant enzymes were identified by analyzing the nucleotide sequence of the genes. A mutant with the most desirable product profile from each library, defined as the most reduced 1-indenol concentration and with the highest cis-(1S,2R)-indandiol enantiomeric excess, was used to perform each subsequent round of mutagenesis. After three rounds of mutagenesis and screening, mutant 1C4-3G was identified to have a threefold reduction in 1-indenol formation over the wild type (20% vs 60% of total products) and a 40% increase of product (cis-indandiol) yield.

  18. A liquid chromatography-mass spectrometry method for the quantification of bioavailability and bioconversion of beta-carotene to retinol in humans

    NARCIS (Netherlands)

    Yan Wang,; Xiaoying Xu,; Lieshout, van M.; West, C.E.; Lugtenburg, J.; Verhoeven, M.A.; Creemers, A.F.L.

    2000-01-01

    A method based on high-performance liquid chromatography-atmospheric pressure chemical ionization mass spectrometry (APCI LC-MS) was developed for the quantification of the bioavailability of retinyl palmitate and -carotene and the bioconversion of -carotene to retinol in humans. Following oral

  19. Application of continuous stirred membrane reactor to 3-cyanopyridine bioconversion using the nitrile hydratase–amidase cascade system of Microbacterium imperiale CBS 498-74

    Czech Academy of Sciences Publication Activity Database

    Cantarella, L.; Gallifuoco, A.; Malandra, A.; Martínková, Ludmila; Pasquarelli, F.; Spera, A.; Cantarella, M.

    2010-01-01

    Roč. 47, č. 3 (2010), s. 64-70 ISSN 0141-0229 R&D Projects: GA MŠk OC09046 Institutional research plan: CEZ:AV0Z50200510 Keywords : Nitrile hydratase-amidase cascade system * 3-Cyanopyridine bioconversion * Nicotinamide Subject RIV: EE - Microbiology, Virology Impact factor: 2.287, year: 2010

  20. Development of thermophilic tailor-made enzyme mixtures for the bioconversion of agricultural and forest residues

    Directory of Open Access Journals (Sweden)

    Anthi eKarnaouri

    2016-02-01

    Full Text Available Even though the main components of all lignocellulosic feedstocks include cellulose, hemicellulose, as well as the protective lignin matrix, there are some differences in structure, such as in hardwoods and softwoods, which may influence the degradability of the materials. Under this view, various types of biomass might require a minimal set of enzymes that has to be tailor-made. Partially defined complex mixtures that are currently commercially used are not adapted to efficiently degrade different materials, so novel enzyme mixtures have to be customized. Development of these cocktails requires better knowledge about the specific activities involved, in order to optimize hydrolysis. The role of filamentous fungus Myceliophthora thermophila and its complete enzymatic repertoire for the bioconversion of complex carbohydrates has been widely proven. In this study, four core cellulases (MtCBH7, MtCBH6, MtEG5 and MtEG7, in the presence of other four accessory enzymes (mannanase, lytic polyssacharide monooxygenase MtGH61, xylanase, MtFae1a and β-glucosidase MtBGL3, were tested as a 9-component cocktail against one model substrate (phosphoric acid swollen cellulose and four hydrothermally pretreated natural substrates (wheat straw as an agricultural waste, birch and spruce biomass, as forest residues. Synergistic interactions among different enzymes were determined using a suitable design of experiments methodology. The results suggest that for the hydrolysis of the pure substrate (PASC, high proportions of MtEG7 are needed for efficient yields. MtCBH7 and MtEG7 are enzymes of major importance during the hydrolysis of pretreated wheat straw, while MtCBH7 plays a crucial role in case of spruce. Cellobiohydrolases MtCBH6 and MtCBH7 act in combination and are key enzymes for the hydrolysis of the hardwood (birch. Optimum combinations were predicted from suitable statistical models which were able to further increase hydrolysis yields, suggesting that

  1. Effects of moisture content of food waste on residue separation, larval growth and larval survival in black soldier fly bioconversion.

    Science.gov (United States)

    Cheng, Jack Y K; Chiu, Sam L H; Lo, Irene M C

    2017-09-01

    In order to foster sustainable management of food waste, innovations in food waste valorization technologies are crucial. Black soldier fly (BSF) bioconversion is an emerging technology that can turn food waste into high-protein fish feed through the use of BSF larvae. The conventional method of BSF bioconversion is to feed BSF larvae with food waste directly without any moisture adjustment. However, it was reported that difficulty has been experienced in the separation of the residue (larval excreta and undigested material) from the insect biomass due to excessive moisture. In addition to the residue separation problem, the moisture content of the food waste may also affect the growth and survival aspects of BSF larvae. This study aims to determine the most suitable moisture content of food waste that can improve residue separation as well as evaluate the effects of the moisture content of food waste on larval growth and survival. In this study, pre-consumer and post-consumer food waste with different moisture content (70%, 75% and 80%) was fed to BSF larvae in a temperature-controlled rotary drum reactor. The results show that the residue can be effectively separated from the insect biomass by sieving using a 2.36mm sieve, for both types of food waste at 70% and 75% moisture content. However, sieving of the residue was not feasible for food waste at 80% moisture content. On the other hand, reduced moisture content of food waste was found to slow down larval growth. Hence, there is a trade-off between the sieving efficiency of the residue and the larval growth rate. Furthermore, the larval survival rate was not affected by the moisture content of food waste. A high larval survival rate of at least 95% was achieved using a temperature-controlled rotary drum reactor for all treatment groups. The study provides valuable insights for the waste management industry on understanding the effects of moisture content when employing BSF bioconversion for food waste recycling

  2. Real-time monitoring of intracellular redox changes in Methylococcus capsulatus (Bath) for efficient bioconversion of methane to methanol.

    Science.gov (United States)

    Ishikawa, Masahito; Tanaka, Yuya; Suzuki, Risa; Kimura, Kota; Tanaka, Kenya; Kamiya, Kazuhide; Ito, Hidehiro; Kato, Souichiro; Kamachi, Toshiaki; Hori, Katsutoshi; Nakanishi, Shuji

    2017-10-01

    This study aimed to develop a novel method for real-time monitoring of the intracellular redox states in a methanotroph Methylococcus capsulatus, using Peredox as a genetically encoded fluorescent sensor of the NADH:NAD + ratio. As expected, the fluorescence derived from the Peredox-expressing M. capsulatus transformant increased by supplementation of electron donor compounds (methane and formate), while it decreased by specifically inhibiting the methanol oxidation reaction. Electrochemical measurements confirmed that the Peredox fluorescence reliably represents the intracellular redox changes. This study is the first to construct a reliable redox-monitoring method for methanotrophs, which will facilitate to develop more efficient methane-to-methanol bioconversion processes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Dynamic bioconversion mathematical modelling and simulation of urban organic waste co-digestion in continuously stirred tank reactor

    DEFF Research Database (Denmark)

    Fitamo, Temesgen Mathewos; Boldrin, Alessio; Dorini, G.

    of this study was to apply a dynamic mathematical model to simulate the co-digestion of different urban organic wastes (UOW). The modelling was based on experimental activities, during which two reactors (R1, R2) were operated at hydraulic retention times (HRT) of 30, 20, 15, 10 days, in thermophilic conditions......The application of anaerobic digestion (AD) as process technology is increasing worldwide: the production of biogas, a versatile form of renewable energy, from biomass and organic waste materials allows mitigating greenhouse gas emission from the energy and transportation sectors while treating...... waste. However, the successful operation of AD processes is challenged by economic and technological issues. To overcome these barriers, mathematical modelling of the bioconversion process can provide support to develop strategies for controlling and optimizing the AD process. The objective...

  4. An Effective Method to Detect Volatile Intermediates Generated in the Bioconversion of Coal to Methane by Gas Chromatography-Mass Spectrometry after In-Situ Extraction Using Headspace Solid-Phase Micro-Extraction under Strict Anaerobic Conditions.

    Science.gov (United States)

    Liu, Jianmin; Wang, Baoyu; Tai, Chao; Wu, Li; Zhao, Han; Guan, Jiadong; Chen, Linyong

    2016-01-01

    Bioconversion of coal to methane has gained increased attention in recent decades because of its economic and environmental advantages. However, the mechanism of this process is difficult to study in depth, partly because of difficulties associated with the analysis of intermediates generated in coal bioconversion. In this investigation, we report on an effective method to analyze volatile intermediates generated in the bioconversion of coal under strict anaerobic conditions. We conduct in-situ extraction of intermediates using headspace solid-phase micro-extraction followed by detection by gas chromatography-mass spectrometry. Bioconversion simulation equipment was modified and combined with a solid-phase micro-extraction device. In-situ extraction could be achieved by using the combined units, to avoid a breakdown in anaerobic conditions and to maintain the experiment continuity. More than 30 intermediates were identified qualitatively in the conversion process, and the variation in trends of some typical intermediates has been discussed. Volatile organic acids (C2-C7) were chosen for a quantitative study of the intermediates because of their importance during coal bioconversion to methane. Fiber coating, extraction time, and solution acidity were optimized in the solid-phase micro-extraction procedure. The pressure was enhanced during the bioconversion process to investigate the influence of headspace pressure on analyte extraction. The detection limits of the method ranged from 0.0006 to 0.02 mmol/L for the volatile organic acids and the relative standard deviations were between 4.6% and 11.5%. The volatile organic acids (C2-C7) generated in the bioconversion process were 0.01-1.15 mmol/L with a recovery range from 80% to 105%. The developed method is useful for further in-depth research on the bioconversion of coal to methane.

  5. Bioconversion of Gibberellin Fermentation Residue into Feed Supplement and Organic Fertilizer Employing Housefly (Musca domestica L. Assisted by Corynebacterium variabile.

    Directory of Open Access Journals (Sweden)

    Sen Yang

    Full Text Available The accumulation of a considerable quantity of gibberellin fermentation residue (GFR during gibberellic acid A3 (GA3 production not only results in the waste of many resources, but also poses a potential hazard to the environment, indicating that the safe treatment of GFR has become an urgent issue for GA3 industry. The key to recycle GFR is converting it into an available resource and removing the GA3 residue. To this end, we established a co-bioconversion process in this study using house fly larvae (HFL and microbes (Corynebacterium variabile to convert GFR into insect biomass and organic fertilizer. About 85.5% GA3 in the GFR was removed under the following optimized solid-state fermentation conditions: 60% GFR, 40% rice straw powder, pH 8.5 and 6 days at 26 °C. A total of 371 g housefly larvae meal and 2,064 g digested residue were bio-converted from 3,500 g raw GFR mixture contaning1, 400 g rice straw in the unit of (calculated dry matter. HFL meal derived from GFR contained 56.4% protein, 21.6% fat, and several essential amino acids, suggesting that it is a potential alternative animal feed protein source. Additionally, the digested GFR could be utilized as an organic fertilizer with a content of 3.2% total nitrogen, 2.0% inorganic phosphorus, 1.3% potassium and 91.5% organic matter. This novel GFR bio-conversion method can mitigate potential environmental pollution and recycle the waste resources.

  6. Bioconversion of Gibberellin Fermentation Residue into Feed Supplement and Organic Fertilizer Employing Housefly (Musca domestica L.) Assisted by Corynebacterium variabile

    Science.gov (United States)

    Yang, Sen; Xie, Jiufeng; Hu, Nan; Liu, Yixiong; Zhang, Jiner; Ye, Xiaobin; Liu, Ziduo

    2015-01-01

    The accumulation of a considerable quantity of gibberellin fermentation residue (GFR) during gibberellic acid A3 (GA3) production not only results in the waste of many resources, but also poses a potential hazard to the environment, indicating that the safe treatment of GFR has become an urgent issue for GA3 industry. The key to recycle GFR is converting it into an available resource and removing the GA3 residue. To this end, we established a co-bioconversion process in this study using house fly larvae (HFL) and microbes (Corynebacterium variabile) to convert GFR into insect biomass and organic fertilizer. About 85.5% GA3 in the GFR was removed under the following optimized solid-state fermentation conditions: 60% GFR, 40% rice straw powder, pH 8.5 and 6 days at 26°C. A total of 371g housefly larvae meal and 2,064g digested residue were bio-converted from 3,500g raw GFR mixture contaning1, 400g rice straw in the unit of (calculated) dry matter. HFL meal derived from GFR contained 56.4% protein, 21.6% fat, and several essential amino acids, suggesting that it is a potential alternative animal feed protein source. Additionally, the digested GFR could be utilized as an organic fertilizer with a content of 3.2% total nitrogen, 2.0% inorganic phosphorus, 1.3% potassium and 91.5% organic matter. This novel GFR bio-conversion method can mitigate potential environmental pollution and recycle the waste resources. PMID:25992605

  7. The synthesis of alternatives for the bioconversion of waste-monoethanolamine from large-scale CO{sub 2}-removal processes

    Energy Technology Data Exchange (ETDEWEB)

    Ohtaguchi, Kazuhisa; Yokoyama, Takahisa [Tokyo Inst. of Tech. (Japan). Dept. of Chemical Engineering

    1998-12-31

    The alternatives for bioconversion of monoethanolamine (MEA), which would appear in large quantities in industrial effluent of CO{sub 2}-removal process of power companies, have been proposed by investigating the ability of some microorganisms to deaminate MEA. An evaluation of biotechnology, which includes productions from MEA of acetic acid and acetaldehyde with Escherichia coli, of formic and acetic acids with Clostridium formicoaceticum, confirms and extends our earlier remarks on availability of ecotechnology for solving the above problem. (Author)

  8. Research report of fiscal 1997. Survey on creation of high-efficiency renewable resources, and bioconversion technology; 1997 nendo chosa hokokusho. Kokoritsu saisei kano shigen no sosei narabi ni bioconversion gijutsu ni kansuru chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    Survey was made on material production technology using creation technology of high-efficiency renewable resources (photosynthesis reaction of plants). Industrially usable plant resources in overseas countries and Japan were arranged, and plant resources unused for food were also surveyed. The present state of genetic engineering necessary for metabolic engineering of higher plants such as fit and high-expression technology of genes, plant cell cultivation, and control technology of plant cell multiplication is described, and elementary technologies required for future gene-recombined plants are predicted. Survey was also made on the trend of creation technology of industrial plants for fat and oil, biodegradable polyester, amino acid, cellulose, fiber (cotton) and forest wood. A patent list on plant biotechnology was prepared, and study on bioconversion of plant resources was also surveyed. Overseas R & D trends on conversion and effective use technologies of renewable bio- resources are reported, and process design and its profitability were evaluated through a case study. 414 refs., 87 figs., 55 tabs.

  9. The bioconversion of mountain pine beetle-killed lodgepole pine to fuel ethanol using the organosolv process.

    Science.gov (United States)

    Pan, Xuejun; Xie, Dan; Yu, Richard W; Saddler, Jack N

    2008-09-01

    Lodgepole pine (Pinus contorta) killed by mountain pine beetle (Dendroctonus ponderosae) (BLP) was compared with healthy lodgepole pine (HLP) for bioconversion to ethanol and high-value co-products. The BLP and HLP chips were pretreated using an ethanol organosolv process at a variety of severities. It was shown that the BLP was easier to pretreat and delignify than were the HLP chips. The resulting pretreated BLP substrate had a lower residual lignin, lower degree of polymerization of cellulose, lower cellulose crystallinity, smaller fiber size and thereby a better enzymatic hydrolysability than did the HLP substrates. However, under the same conditions, the BLP showed lower substrate yield and cellulose recovery than did the HLP, which likely resulted from the excessive hydrolysis and subsequent decomposition of the cellulose and hemicellulose during the pretreatment. The BLP wood yielded more ethanol organosolv lignin than was obtained with the HLP material. The HLP lignin had a lower molecular weight and narrower distribution than did the BLP lignin. It appears that the beetle killed LP is more receptive to organosolv pretreatment other than a slightly lower recovery of carbohydrates.

  10. Fermentation products of solvent tolerant marine bacterium Moraxella spp. MB1 and its biotechnological applications in salicylic acid bioconversion.

    Directory of Open Access Journals (Sweden)

    Solimabi Wahidullah

    Full Text Available As part of a proactive approach to environmental protection, emerging issues with potential impact on the environment is the subject of ongoing investigation. One emerging area of environmental research concerns pharmaceuticals like salicylic acid, which is the main metabolite of various analgesics including aspirin. It is a common component of sewage effluent and also an intermediate in the degradation pathway of various aromatic compounds which are introduced in the marine environment as pollutants. In this study, biotransformation products of salicylic acid by seaweed, Bryopsis plumosa, associated marine bacterium, Moraxella spp. MB1, have been investigated. Phenol, conjugates of phenol and hydroxy cinnamic acid derivatives (coumaroyl, caffeoyl, feruloyl and trihydroxy cinnamyl with salicylic acid (3-8 were identified as the bioconversion products by electrospray ionization mass spectrometry. These results show that the microorganism do not degrade phenolic acid but catalyses oxygen dependent transformations without ring cleavage. The degradation of salicylic acid is known to proceed either via gentisic acid pathway or catechol pathway but this is the first report of biotransformation of salicylic acid into cinnamates, without ring cleavage. Besides cinnamic acid derivatives (9-12, metabolites produced by the bacterium include antimicrobial indole (13 and β-carbolines, norharman (14, harman (15 and methyl derivative (16, which are beneficial to the host and the environment.

  11. Development of rapid bioconversion with integrated recycle technology for ethanol production from extractive ammonia pretreated corn stover.

    Science.gov (United States)

    Jin, Mingjie; Liu, Yanping; da Costa Sousa, Leonardo; Dale, Bruce E; Balan, Venkatesh

    2017-08-01

    High enzyme loading and low productivity are two major issues impeding low cost ethanol production from lignocellulosic biomass. This work applied rapid bioconversion with integrated recycle technology (RaBIT) and extractive ammonia (EA) pretreatment for conversion of corn stover (CS) to ethanol at high solids loading. Enzymes were recycled via recycling unhydrolyzed solids. Enzymatic hydrolysis with recycled enzymes and fermentation with recycled yeast cells were studied. Both enzymatic hydrolysis time and fermentation time were shortened to 24 h. Ethanol productivity was enhanced by two times and enzyme loading was reduced by 30%. Glucan and xylan conversions reached as high as 98% with an enzyme loading of as low as 8.4 mg protein per g glucan. The overall ethanol yield was 227 g ethanol/kg EA-CS (191 g ethanol/kg untreated CS). Biotechnol. Bioeng. 2017;114: 1713-1720. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  12. Utilization of fruit peels as carbon source for white rot fungi biomass production under submerged state bioconversion

    Directory of Open Access Journals (Sweden)

    Olorunnisola Kola Saheed

    2016-04-01

    Full Text Available The present generation of nutrient rich waste streams within the food and hospitality industry is inevitable and remained a matter of concern to stakeholders. Three white rot fungal strains were cultivated under submerged state bioconversion (SmB. Fermentable sugar conversion efficiency, biomass production and substrate utilization constant were indicators used to measure the success of the process. The substrates – banana peel (Bp, pineapple peel (PAp and papaya peel (Pp were prepared in wet and dried forms as substrates. Phanerochaete chrysosporium (P. chrysosporium, Panus tigrinus M609RQY, and RO209RQY were cultivated on sole fruit wastes and their composites. All fungal strains produced profound biomass on dry sole wet substrates, but wet composite substrates gave improved results. P. tigrinus RO209RQY was the most efficient in sugar conversion (99.6% on sole substrates while P. tigrinus M609RQY was efficient on composite substrates. Elevated substrate utilization constant (Ku and biomass production heralded wet composite substrates. P. chrysosporium was the most performing fungal strain for biomass production, while PApBp was the best composite substrate.

  13. Highly Selective Bioconversion of Ginsenoside Rb1 to Compound K by the Mycelium of Cordyceps sinensis under Optimized Conditions

    Directory of Open Access Journals (Sweden)

    Wei-Nan Wang

    2015-10-01

    Full Text Available Compound K (CK, a highly active and bioavailable derivative obtained from protopanaxadiol ginsenosides, displays a wide variety of pharmacological properties, especially antitumor activity. However, the inadequacy of natural sources limits its application in the pharmaceutical industry. In this study, we firstly discovered that Cordyceps sinensis was a potent biocatalyst for the biotransformation of ginsenoside Rb1 into CK. After a series of investigations on the biotransformation parameters, an optimal composition of the biotransformation culture was found to be lactose, soybean powder and MgSO4 without controlling the pH. Also, an optimum temperature of 30 °C for the biotransformation process was suggested in a range of 25 °C–50 °C. Then, a biotransformation pathway of Rb1 → Rd → F2 → CK was established using high performance liquid chromatography/quadrupole time-of-flight mass spectrometry (HPLC-Q-TOF-MS. Our results demonstrated that the molar bioconversion rate of Rb1 to CK was more than 82% and the purity of CK produced by C. sinensis under the optimized conditions was more than 91%. In conclusion, the combination of C. sinensis and the optimized conditions is applicable for the industrial preparation of CK for medicinal purposes.

  14. A Two-Step Bioconversion Process for Canolol Production from Rapeseed Meal Combining an Aspergillus niger Feruloyl Esterase and the Fungus Neolentinus lepideus.

    Science.gov (United States)

    Odinot, Elise; Fine, Frédéric; Sigoillot, Jean-Claude; Navarro, David; Laguna, Oscar; Bisotto, Alexandra; Peyronnet, Corinne; Ginies, Christian; Lecomte, Jérôme; Faulds, Craig B; Lomascolo, Anne

    2017-10-14

    Rapeseed meal is a cheap and abundant raw material, particularly rich in phenolic compounds of biotechnological interest. In this study, we developed a two-step bioconversion process of naturally occurring sinapic acid (4-hydroxy-3,5-dimethoxycinnamic acid) from rapeseed meal into canolol by combining the complementary potentialities of two filamentous fungi, the micromycete Aspergillus niger and the basidiomycete Neolentinus lepideus . Canolol could display numerous industrial applications because of its high antioxidant, antimutagenic and anticarcinogenic properties. In the first step of the process, the use of the enzyme feruloyl esterase type-A (named AnFaeA) produced with the recombinant strain A. niger BRFM451 made it possible to release free sinapic acid from the raw meal by hydrolysing the conjugated forms of sinapic acid in the meal (mainly sinapine and glucopyranosyl sinapate). An amount of 39 nkat AnFaeA per gram of raw meal, at 55 °C and pH 5, led to the recovery of 6.6 to 7.4 mg of free sinapic acid per gram raw meal, which corresponded to a global hydrolysis yield of 68 to 76% and a 100% hydrolysis of sinapine. Then, the XAD2 adsorbent (a styrene and divinylbenzene copolymer resin), used at pH 4, enabled the efficient recovery of the released sinapic acid, and its concentration after elution with ethanol. In the second step, 3-day-old submerged cultures of the strain N. lepideus BRFM15 were supplied with the recovered sinapic acid as the substrate of bioconversion into canolol by a non-oxidative decarboxylation pathway. Canolol production reached 1.3 g/L with a molar yield of bioconversion of 80% and a productivity of 100 mg/L day. The same XAD2 resin, when used at pH 7, allowed the recovery and purification of canolol from the culture broth of N. lepideus . The two-step process used mild conditions compatible with green chemistry.

  15. [Phase transfer catalyzed bioconversion of penicillin G to 6-APA by immobilized penicillin acylase in recyclable aqueous two-phase systems with light/pH sensitive copolymers].

    Science.gov (United States)

    Jin, Ke-ming; Cao, Xue-jun; Su, Jin; Ma, Li; Zhuang, Ying-ping; Chu, Ju; Zhang, Si-liang

    2008-03-01

    Immobilized penicillin acylase was used for bioconversion of penicillin PG into 6-APA in aqueous two-phase systems consisting of a light-sensitive polymer PNBC and a pH-sensitive polymer PADB. Partition coefficients of 6-APA was found to be about 5.78 in the presence of 1% NaCl. Enzyme kinetics showed that the reaction reached equilibrium at roughly 7 h. The 6-APA mole yields were 85.3% (pH 7.8, 20 degrees C), with about 20% increment as compared with the reaction of single aqueous phase buffer. The partition coefficient of PG (Na) varied scarcely, while that of the product, 6-APA and phenylacetic acid (PA) significantly varied due to Donnan effect of the phase systems and hydrophobicity of the products. The variation of the partition coefficients of the products also affected the bioconversion yield of the products. In the aqueous two-phase systems, the substrate, PG, the products of 6-APA and PA were biased in the top phase, while immobilized penicillin acylase at completely partitioned at the bottom. The substrate and PG entered the bottom phase, where it was catalyzed into 6-APA and PA and entered the top phase. Inhibition of the substrate and products was removed to result in improvement of the product yield, and the immobilized enzyme showed higher efficiency than the immobilized cells and occupied smaller volume. Compared with the free enzyme, immobilized enzyme had greater stability, longer life-time, and was completely partitioned in the bottom phase and recycle. Bioconversion in two-phase systems using immobilized penicillin acylase showed outstanding advantage. The light-sensitive copolymer forming aqueous two-phase systems could be recovered by laser radiation at 488 nm or filtered 450 nm light, while pH-sensitive polymer PADB could be recovered at the isoelectric point (pH 4.1). The recovery of the two copolymers was between 95% and 99%.

  16. Temperature Increase Negatively Affects the Fatty Acid Bioconversion Capacity of Rainbow Trout (Oncorhynchus mykiss) Fed a Linseed Oil-Based Diet.

    Science.gov (United States)

    Mellery, Julie; Geay, Florian; Tocher, Douglas R; Kestemont, Patrick; Debier, Cathy; Rollin, Xavier; Larondelle, Yvan

    2016-01-01

    Aquaculture is meant to provide fish rich in omega-3 long chain polyunsaturated fatty acids (n-3 LC-PUFA). This objective must be reached despite (1) the necessity to replace the finite and limited fish oil in feed production and (2) the increased temperature of the supply water induced by the global warming. The objective of the present paper was to determine to what extent increased water temperature influences the fatty acid bioconversion capacity of rainbow trout (Oncorhynchus mykiss) fed a plant-derived diet. Fish were fed two diets formulated with fish oil (FO) or linseed oil (LO) as only added lipid source at the optimal water temperature of 15°C or at the increased water temperature of 19°C for 60 days. We observed that a temperature increase close to the upper limit of the species temperature tolerance range negatively affected the feed efficiency of rainbow trout fed LO despite a higher feed intake. The negative impact of increased water temperature on fatty acid bioconversion capacity appeared also to be quite clear considering the reduced expression of fatty acid desaturase 2 in liver and intestine and the reduced Δ6 desaturase enzymatic activity in intestinal microsomes. The present results also highlighted a negative impact of increased temperature on the apparent in vivo enzymatic activity of Δ5 and Δ6 desaturases of fish fed LO. Interestingly, this last parameter appeared less affected than those mentioned above. This study highlights that the increased temperature that rainbow trout may face due to global warming could reduce their fatty acid bioconversion capacity. The unavoidable replacement of finite fish oil by more sustainable, readily available and economically viable alternative lipid sources in aquaculture feeds should take this undeniable environmental issue on aquaculture productivity into account.

  17. Microbial community structures in high rate algae ponds for bioconversion of agricultural wastes from livestock industry for feed production.

    Science.gov (United States)

    Mark Ibekwe, A; Murinda, Shelton E; Murry, Marcia A; Schwartz, Gregory; Lundquist, Trygve

    2017-02-15

    Dynamics of seasonal microbial community compositions in algae cultivation ponds are complex. However, there is very limited knowledge on bacterial communities that may play significant roles with algae in the bioconversion of manure nutrients to animal feed. In this study, water samples were collected during winter, spring, summer, and fall from the dairy lagoon effluent (DLE), high rate algae ponds (HRAP) that were fed with diluted DLE, and municipal waste water treatment plant (WWTP) effluent which was included as a comparison system for the analysis of total bacteria, Cyanobacteria, and microalgae communities using MiSeq Illumina sequencing targeting the 16S V4 rDNA region. The main objective was to examine dynamics in microbial community composition in the HRAP used for the production of algal biomass. DNA was extracted from the different sample types using three commercially available DNA extraction kits; MoBio Power water extraction kit, Zymo fungi/bacterial extraction kit, and MP Biomedicals FastDNA SPIN Kit. Permutational analysis of variance (PERMANOVA) using distance matrices on each variable showed significant differences (P=0.001) in beta-diversity based on sample source. Environmental variables such as hydraulic retention time (HRT; P<0.031), total N (P<0.002), total inorganic N (P<0.002), total P (P<0.002), alkalinity (P<0.002), pH (P<0.022), total suspended solid (TSS; P<0.003), and volatile suspended solids (VSS; P<0.002) significantly affected microbial communities in DLE, HRAP, and WWTP. Of the operational taxonomic units (OTUs) identified to phyla level, the dominant classes of bacteria identified were: Cyanobacteria, Alpha-, Beta-, Gamma-, Epsilon-, and Delta-proteobacteria, Bacteroidetes, Firmicutes, and Planctomycetes. Our data suggest that microbial communities were significantly affected in HRAP by different environmental variables, and care must be taken in extraction procedures when evaluating specific groups of microbial communities for

  18. Optimization of Eisenia fetida stocking density for the bioconversion of rock phosphate enriched cow dung–waste paper mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Unuofin, F.O., E-mail: funmifrank2009@gmail.com; Mnkeni, P.N.S., E-mail: pmnkeni@ufh.ac.za

    2014-11-15

    Highlights: • Vermidegradation of RP-enriched waste mixtures is dependent on E. fetida stocking density. • A stocking density of 12.5 g-worms kg{sup -1} resulted in highly humified vermicomposts. • P release from RP-enriched waste vermicomposts increases with E. fetida stocking density. • RP-enriched waste vermicomposts had no inhibitory effect on seed germination. - Abstract: Vermitechnology is gaining recognition as an environmental friendly waste management strategy. Its successful implementation requires that the key operational parameters like earthworm stocking density be established for each target waste/waste mixture. One target waste mixture in South Africa is waste paper mixed with cow dung and rock phosphate (RP) for P enrichment. This study sought to establish optimal Eisenia fetida stocking density for maximum P release and rapid bioconversion of RP enriched cow dung–paper waste mixtures. E. fetida stocking densities of 0, 7.5, 12.5, 17.5 and 22.5 g-worms kg{sup −1} dry weight of cow dung–waste paper mixtures were evaluated. The stocking density of 12.5 g-worms kg{sup −1} resulted in the highest earthworm growth rate and humification of the RP enriched waste mixture as reflected by a C:N ratio of <12 and a humic acid/fulvic acid ratio of >1.9 in final vermicomposts. A germination test revealed that the resultant vermicompost had no inhibitory effect on the germination of tomato, carrot, and radish. Extractable P increased with stocking density up to 22.5 g-worm kg{sup −1} feedstock suggesting that for maximum P release from RP enriched wastes a high stocking density should be considered.

  19. Optimization of Eisenia fetida stocking density for the bioconversion of rock phosphate enriched cow dung–waste paper mixtures

    International Nuclear Information System (INIS)

    Unuofin, F.O.; Mnkeni, P.N.S.

    2014-01-01

    Highlights: • Vermidegradation of RP-enriched waste mixtures is dependent on E. fetida stocking density. • A stocking density of 12.5 g-worms kg -1 resulted in highly humified vermicomposts. • P release from RP-enriched waste vermicomposts increases with E. fetida stocking density. • RP-enriched waste vermicomposts had no inhibitory effect on seed germination. - Abstract: Vermitechnology is gaining recognition as an environmental friendly waste management strategy. Its successful implementation requires that the key operational parameters like earthworm stocking density be established for each target waste/waste mixture. One target waste mixture in South Africa is waste paper mixed with cow dung and rock phosphate (RP) for P enrichment. This study sought to establish optimal Eisenia fetida stocking density for maximum P release and rapid bioconversion of RP enriched cow dung–paper waste mixtures. E. fetida stocking densities of 0, 7.5, 12.5, 17.5 and 22.5 g-worms kg −1 dry weight of cow dung–waste paper mixtures were evaluated. The stocking density of 12.5 g-worms kg −1 resulted in the highest earthworm growth rate and humification of the RP enriched waste mixture as reflected by a C:N ratio of <12 and a humic acid/fulvic acid ratio of >1.9 in final vermicomposts. A germination test revealed that the resultant vermicompost had no inhibitory effect on the germination of tomato, carrot, and radish. Extractable P increased with stocking density up to 22.5 g-worm kg −1 feedstock suggesting that for maximum P release from RP enriched wastes a high stocking density should be considered

  20. Tartronate semialdehyde reductase defines a novel rate-limiting step in assimilation and bioconversion of glycerol in Ustilago maydis.

    Directory of Open Access Journals (Sweden)

    Yanbin Liu

    Full Text Available BACKGROUND: Glycerol is a by-product of biodiesel production. Currently, it has limited applications with low bioconversion efficiency to most metabolites reported. This is partly attributed to the poor knowledge on the glycerol metabolic pathway in bacteria and fungi. METHODOLOGY/PRINCIPAL FINDINGS: We have established a fast screening method for identification of genes that improve glycerol utilization in Ustilago maydis. This was done by comparing the growth rates of T-DNA tagged mutant colonies on solid medium using glycerol as the sole carbon source. We present a detailed characterization of one of the mutants, GUM1, which contains a T-DNA element inserted into the promoter region of UM02592 locus (MIPS Ustilago maydis database, MUMDB, leading to enhanced and constitutive expression of its mRNA. We have demonstrated that um02592 encodes a functional tartronate semialdehyde reductase (Tsr1, which showed dual specificity to cofactors NAD(+ and NADP(+ and strong substrate specificity and enantioselectivity for D-glycerate. Improved glycerol assimilation in GUM1 was associated with elevated expression of tsr1 mRNA and this could be phenocopied by over-expression of the gene. Glycolipid accumulation was reduced by 45.2% in the knockout mutant whereas introduction of an extra copy of tsr1 driven by the glyceraldehyde phosphate dehydrogenase promoter increased it by 40.4%. CONCLUSIONS/SIGNIFICANCE: Our results demonstrate that tartronate semialdehyde reductase (TSR plays an important role in glycerol assimilation in U. maydis and defines a novel target in genetic engineering for improved conversion of glycerol to higher value products. Our results add significant depth to the understanding of the glycerol metabolic pathway in fungi. We have demonstrated, for the first time, a biological role of a eukaryotic TSR.

  1. Shiitake Medicinal Mushroom, Lentinus edodes (Higher Basidiomycetes) Productivity and Lignocellulolytic Enzyme Profiles during Wheat Straw and Tree Leaf Bioconversion.

    Science.gov (United States)

    Elisashvili, Vladimir; Kachlishvili, Eva; Asatiani, Mikheil D

    2015-01-01

    Two commercial strains of Lentinus edodes have been comparatively evaluated for their productivity and lignocellulolytic enzyme profiles in mushroom cultivation using wheat straw or tree leaves as the growth substrates. Both substrates are profitable for recycling into shiitake fruit bodies. L. edodes 3715 gave the lowest yield of mushroom during tree leaves bioconversion with the biological efficiency (BE) 74.8% while the L. edodes 3721 BE achieved 83.4%. Cultivation of shiitake on wheat straw, especially in the presence of additional nitrogen source, increased the L. edodes 3721 BE to 92-95.3% owing to the high hydrolases activity and favorable conditions. Despite the quantitative variations, each strain of L. edodes had a similar pattern for secreting enzymes into the wheat straw and tree leaves. The mushrooms laccase and MnP activities were high during substrate colonization and declined rapidly during primordia appearance and fruit body development. While oxidase activity decreased, during the same period cellulases and xylanase activity raised sharply. Both cellulase and xylanase activity peaked at the mature fruit body stage. When mushrooms again shifted to the vegetative growth, oxidase activity gradually increased, whereas the hydrolases activity dropped rapidly. The MnP, CMCase, and FP activities of L. edodes 3721 during cultivation on wheat straw were higher than those during mushroom growth on tree leaves whereas the laccase activity was rather higher in fermentation of tree leaves. Enrichment of wheat straw with an additional nitrogen source rather favored to laccase, MnP, and FPA secretion during the vegetative stage of the L. edodes 3721 growth.

  2. Bioconversion of Scutellaria baicalensis extract can increase recovery of auditory function in a mouse model of noise-induced hearing loss.

    Science.gov (United States)

    Rodriguez, Isabel; Hong, Bin Na; Nam, Youn Hee; Kim, Eun Young; Park, Geun Ha; Ji, Min Gun; Kang, Tong Ho

    2017-09-01

    In noise-induced hearing loss (NIHL), noise exposure damages cochlear sensory hair cells, which lack the capacity to regenerate. Following noise insult, intense metabolic activity occurs, resulting in a cochlear free radical imbalance. Oxidative stress and antioxidant enzyme alterations, including lipoxygenase upregulation, have been linked to chronic inflammation, which contributes to hearing impairment. We previously proposed Scutellaria baicalensis (SB) extract as an alternative therapeutic for preventing NIHL and attributed its pharmacological effects to baicalein. Although baicalein was most effective, its concentration in SB extract is much lower compared to baicalin. In this study, we performed enzymatic bioconversion using an Sumizyme (SM) enzyme to increase baicalein concentration in SB extract and consequently improve its therapeutic efficacy. HPLC analysis revealed that baicalein concentration in SB extract after bioconversion (BSB) was significantly increased. Moreover, BSB-treated mice exhibited significantly improved auditory function compared with control mice and tended to have improved auditory function compared with SB-treated mice. We also demonstrated that BSB effectively stimulates hair cell regeneration compared to SB that did not achieve the same effect in a zebrafish model. Finally, when compared the abilities of SB and BSB to inhibit lipoxygenase (LOX), BSB showed a greater efficacy. Cumulatively, our data suggest that BSB exhibits improved pharmacological properties for treating NIHL compared with SB. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  3. Effect of gamma irradiation on the structure of corn stalks and their subsequent bioconversion into protein-rich mycelial biomass of pleurotus sajor-caju

    Energy Technology Data Exchange (ETDEWEB)

    Awafo, V [Quebec Univ., Montreal, PQ (Canada)

    1994-12-31

    Lignocellulosic biomass like corn stalk is an abundant and renewable resource from which food, feed and chemicals may be derived. Enzymatic hydrolysis of native lignocellulosic material is prohibitively slow due to their compositional heterogeneity and structural complexity. In this work, ground corn stalks (20 mesh) were subjected to gamma irradiation (10-170 Mrads) as pretreatments to make them more susceptible for bioconversion into protein-rich mycelial biomass of Pleurotus sajor-caju NRRL 18757. The irradiation was carried out in air in a {sup 60}Co Underwater Calibrator (UC-15, Nordion International) at a dose rate of 2.5 Mrads/h as measured by Fricke dosimetry. No apparent structural differences were observed under the light microscope. However, the protein synthesis and the proportion of mycelial biomass increased with the increase in both the dose of irradiation and time of fermentation during the bioconversion of 1% corn stalk into mycelial biomass of Pleurotus sajor-caju. Gamma irradiation at the dose of 50 Mrads or lower did not produce any appreciable increase in the amount of protein synthesised. At 170 Mrads, the final product contained 28% protein representing a 2-fold increase from non-irradiated corn stalk and an efficiency of 36% conversion of total utilizable polysaccharides of corn stalks into mycelial biomass. The lag phase during mycelial biomass production was much more prolonged at very high doses indicating possible production of some toxic substances during irradiation. (author). 2 tabs., 6 figs.

  4. Molecular characterization of genes of Pseudomonas sp. strain HR199 involved in bioconversion of vanillin to protocatechuate.

    Science.gov (United States)

    Priefert, H; Rabenhorst, J; Steinbüchel, A

    1997-01-01

    The gene loci vdh, vanA, and vanB, which are involved in the bioconversion of vanillin to protocatechuate by Pseudomonas sp. strain HR199 (DSM 7063), were identified as the structural genes of a novel vanillin dehydrogenase (vdh) and the two subunits of a vanillate demethylase (vanA and vanB), respectively. These genes were localized on an EcoRI fragment (E230), which was cloned from a Pseudomonas sp. strain HR199 genomic library in the cosmid pVK100. The vdh gene was identified on a subfragment (HE35) of E230, and the vanA and vanB genes were localized on a different subfragment (H110) of E230. The nucleotide sequences of fragment HE35 and part of fragment H110 were determined, revealing open reading frames of 1062, 951, and 1446 bp, representing vanA, vanB, and vdh, respectively. The vdh gene was organized in one operon together with a fourth open reading frame (ORF2), of 735 bp, which was located upstream of vdh. The deduced amino acid sequences of vanA and vanB exhibited 78.8 and 62.1% amino acid identity, respectively, to the corresponding gene products from Pseudomonas sp. strain ATCC 19151 (F. Brunel and J. Davison, J. Bacteriol. 170:4924-4930, 1988). The deduced amino acid sequence of the vdh gene exhibited up to 35.3% amino acid identity to aldehyde dehydrogenases from different sources. The deduced amino acid sequence of ORF2 exhibited up to 28.4% amino acid identity to those of enoyl coenzyme A hydratases. Escherichia coli strains harboring fragment E230 cloned in pBluescript SK- converted vanillin to protocatechuate via vanillate, indicating the functional expression of vdh, vanA, and vanB in E. coli. High expression of vdh in E. coli was achieved with HE35 cloned in pBluescript SK-. The resulting recombinant strains converted vanillin to vanillate at a rate of up to 0.3 micromol per min per ml of culture. Transfer of vanA, vanB, and vdh to Alcaligenes eutrophus and to different Pseudomonas strains, which were unable to utilize vanillin or vanillate as

  5. Bioconversion of α-linolenic acid into n-3 long-chain polyunsaturated fatty acid in hepatocytes and ad hoc cell culture optimisation.

    Directory of Open Access Journals (Sweden)

    Ramez Alhazzaa

    Full Text Available This study aimed to establish optimal conditions for a cell culture system that would allow the measurement of 18:3n-3 (ALA bioconversion into n-3 long-chain polyunsaturated fatty acid (n-3 LC-PUFA, and to determine the overall pathway kinetics. Using rat hepatocytes (FaO as model cells, it was established that a maximum 20:5n-3 (EPA production from 50 µM ALA initial concentration was achieved after 3 days of incubation. Next, it was established that a gradual increase in the ALA concentration from 0 up to 125 µM lead to a proportional increase in EPA, without concomitant increase in further elongated or desaturated products, such as 22:5n-3 (DPA and 22:6n-3 (DHA in 3 day incubations. Of interest, ALA bioconversion products were observed in the culture medium. Therefore, in vitro experiments disregarding the medium fatty acid content are underestimating the metabolism efficiency. The novel application of the fatty acid mass balance (FAMB method on cell culture system (cells with medium enabled quantifying the apparent enzymatic activities for the biosynthesis of n-3 LC-PUFA. The activity of the key enzymes was estimated and showed that, under these conditions, 50% (Km of the theoretical maximal (V max = 3654 µmol.g(-1 of cell protein.hour(-1 Fads2 activity on ALA can be achieved with 81 µM initial ALA. Interestingly, the apparent activity of Elovl2 (20:5n-3 elongation was the slowest amongst other biosynthesis steps. Therefore, the possible improvement of Elovl2 activity is suggested toward a more efficient DHA production from ALA. The present study proposed and described an ad hoc optimised cell culture conditions and methodology towards achieving a reliable experimental platform, using FAMB, to assist in studying the efficiency of ALA bioconversion into n-3 LC-PUFA in vitro. The FAMB proved to be a powerful and inexpensive method to generate a detailed description of the kinetics of n-3 LC-PUFA biosynthesis enzymes activities in vitro.

  6. A Two-Step Bioconversion Process for Canolol Production from Rapeseed Meal Combining an Aspergillus niger Feruloyl Esterase and the Fungus Neolentinus lepideus

    Directory of Open Access Journals (Sweden)

    Elise Odinot

    2017-10-01

    Full Text Available Rapeseed meal is a cheap and abundant raw material, particularly rich in phenolic compounds of biotechnological interest. In this study, we developed a two-step bioconversion process of naturally occurring sinapic acid (4-hydroxy-3,5-dimethoxycinnamic acid from rapeseed meal into canolol by combining the complementary potentialities of two filamentous fungi, the micromycete Aspergillus niger and the basidiomycete Neolentinus lepideus. Canolol could display numerous industrial applications because of its high antioxidant, antimutagenic and anticarcinogenic properties. In the first step of the process, the use of the enzyme feruloyl esterase type-A (named AnFaeA produced with the recombinant strain A. niger BRFM451 made it possible to release free sinapic acid from the raw meal by hydrolysing the conjugated forms of sinapic acid in the meal (mainly sinapine and glucopyranosyl sinapate. An amount of 39 nkat AnFaeA per gram of raw meal, at 55 °C and pH 5, led to the recovery of 6.6 to 7.4 mg of free sinapic acid per gram raw meal, which corresponded to a global hydrolysis yield of 68 to 76% and a 100% hydrolysis of sinapine. Then, the XAD2 adsorbent (a styrene and divinylbenzene copolymer resin, used at pH 4, enabled the efficient recovery of the released sinapic acid, and its concentration after elution with ethanol. In the second step, 3-day-old submerged cultures of the strain N. lepideus BRFM15 were supplied with the recovered sinapic acid as the substrate of bioconversion into canolol by a non-oxidative decarboxylation pathway. Canolol production reached 1.3 g/L with a molar yield of bioconversion of 80% and a productivity of 100 mg/L day. The same XAD2 resin, when used at pH 7, allowed the recovery and purification of canolol from the culture broth of N. lepideus. The two-step process used mild conditions compatible with green chemistry.

  7. Bioconversion of Agave tequilana fructans by exo-inulinases from indigenous Aspergillus niger CH-A-2010 enhances ethanol production from raw Agave tequilana juice.

    Science.gov (United States)

    Huitrón, Carlos; Pérez, Rosalba; Gutiérrez, Luís; Lappe, Patricia; Petrosyan, Pavel; Villegas, Jesús; Aguilar, Cecilia; Rocha-Zavaleta, Leticia; Blancas, Abel

    2013-01-01

    Agave tequilana fructans are the source of fermentable sugars for the production of tequila. Fructans are processed by acid hydrolysis or by cooking in ovens at high temperature. Enzymatic hydrolysis is considered an alternative for the bioconversion of fructans. We previously described the isolation of Aspergillus niger CH-A-2010, an indigenous strain that produces extracellular inulinases. Here we evaluated the potential application of A. niger CH-A-2010 inulinases for the bioconversion of A. tequilana fructans, and its impact on the production of ethanol. Inulinases were analyzed by Western blotting and thin layer chromatography. Optimal pH and temperature conditions for inulinase activity were determined. The efficiency of A. niger CH-A-2010 inulinases was compared with commercial enzymes and with acid hydrolysis. The hydrolysates obtained were subsequently fermented by Saccharomyces cerevisiae to determine the efficiency of ethanol production. Results indicate that A. niger CH-A-2010 predominantly produces an exo-inulinase activity. Optimal inulinase activity occurred at pH 5.0 and 50 °C. Hydrolysis of raw agave juice by CH-A-2010 inulinases yielded 33.5 g/l reducing sugars, compared with 27.3 g/l by Fructozyme(®) (Novozymes Corp, Bagsværd, Denmark) and 29.4 g/l by acid hydrolysis. After fermentation of hydrolysates, we observed that the conversion efficiency of sugars into ethanol was 97.5 % of the theoretical ethanol yield for enzymatically degraded agave juice, compared to 83.8 % for acid-hydrolyzed juice. These observations indicate that fructans from raw Agave tequilana juice can be efficiently hydrolyzed by using A. niger CH-A-2010 inulinases, and that this procedure impacts positively on the production of ethanol.

  8. Soymilk residue (okara) as a natural immobilization carrier for Lactobacillus plantarum cells enhances soymilk fermentation, glucosidic isoflavone bioconversion, and cell survival under simulated gastric and intestinal conditions.

    Science.gov (United States)

    Xiudong, Xia; Ying, Wang; Xiaoli, Liu; Ying, Li; Jianzhong, Zhou

    2016-01-01

    Cell immobilization is an alternative to microencapsulation for the maintenance of cells in a liquid medium. However, artificial immobilization carriers are expensive and pose a high safety risk. Okara, a food-grade byproduct from soymilk production, is rich in prebiotics. Lactobacilli could provide health enhancing effects to the host. This study aimed to evaluate the potential of okara as a natural immobilizer for L. plantarum 70810 cells. The study also aimed to evaluate the effects of okara-immobilized L. plantarum 70810 cells (IL) on soymilk fermentation, glucosidic isoflavone bioconversion, and cell resistance to simulated gastric and intestinal stresses. Scanning electron microscopy (SEM) was used to show cells adherence to the surface of okara. Lactic acid, acetic acid and isoflavone analyses in unfermented and fermented soymilk were performed by HPLC with UV detection. Viability and growth kinetics of immobilized and free L. plantarum 70810 cells (FL) were followed during soymilk fermentation. Moreover, changes in pH, titrable acidity and viscosity were measured by conventional methods. For in vitro testing of simulated gastrointestinal resistance, fermented soymilk was inoculated with FL or IL and an aliquot incubated into acidic MRS broth which was conveniently prepared to simulate gastric, pancreatic juices and bile salts. Survival to simulated gastric and intestinal stresses was evaluated by plate count of colony forming units on MRS agar. SEM revealed that the lactobacilli cells attached and bound to the surface of okara. Compared with FL, IL exhibited a significantly higher specific growth rate, shorter lag phase of growth, higher productions of lactic and acetic acids, a faster decrease in pH and increase in titrable acidity, and a higher soymilk viscosity. Similarly, IL in soymilk showed higher productions of daizein and genistein compared with the control. Compared with FL, IL showed reinforced resistance to simulatedgastric and intestinal

  9. Soymilk residue (okara as a natural immobilization carrier for Lactobacillus plantarum cells enhances soymilk fermentation, glucosidic isoflavone bioconversion, and cell survival under simulated gastric and intestinal conditions

    Directory of Open Access Journals (Sweden)

    Xia Xiudong

    2016-11-01

    Full Text Available Cell immobilization is an alternative to microencapsulation for the maintenance of cells in a liquid medium. However, artificial immobilization carriers are expensive and pose a high safety risk. Okara, a food-grade byproduct from soymilk production, is rich in prebiotics. Lactobacilli could provide health enhancing effects to the host. This study aimed to evaluate the potential of okara as a natural immobilizer for L. plantarum 70810 cells. The study also aimed to evaluate the effects of okara-immobilized L. plantarum 70810 cells (IL on soymilk fermentation, glucosidic isoflavone bioconversion, and cell resistance to simulated gastric and intestinal stresses. Scanning electron microscopy (SEM was used to show cells adherence to the surface of okara. Lactic acid, acetic acid and isoflavone analyses in unfermented and fermented soymilk were performed by HPLC with UV detection. Viability and growth kinetics of immobilized and free L. plantarum 70810 cells (FL were followed during soymilk fermentation. Moreover, changes in pH, titrable acidity and viscosity were measured by conventional methods. For in vitro testing of simulated gastrointestinal resistance, fermented soymilk was inoculated with FL or IL and an aliquot incubated into acidic MRS broth which was conveniently prepared to simulate gastric, pancreatic juices and bile salts. Survival to simulated gastric and intestinal stresses was evaluated by plate count of colony forming units on MRS agar. SEM revealed that the lactobacilli cells attached and bound to the surface of okara. Compared with FL, IL exhibited a significantly higher specific growth rate, shorter lag phase of growth, higher productions of lactic and acetic acids, a faster decrease in pH and increase in titrable acidity, and a higher soymilk viscosity. Similarly, IL in soymilk showed higher productions of daizein and genistein compared with the control. Compared with FL, IL showed reinforced resistance to simulatedgastric and

  10. Characterization of hemicellulase and cellulase from the extremely thermophilic bacterium Caldicellulosiruptor owensensis and their potential application for bioconversion of lignocellulosic biomass without pretreatment.

    Science.gov (United States)

    Peng, Xiaowei; Qiao, Weibo; Mi, Shuofu; Jia, Xiaojing; Su, Hong; Han, Yejun

    2015-01-01

    Pretreatment is currently the common approach for improving the efficiency of enzymatic hydrolysis on lignocellulose. However, the pretreatment process is expensive and will produce inhibitors such as furan derivatives and phenol derivatives. If the lignocellulosic biomass can efficiently be saccharified by enzymolysis without pretreatment, the bioconversion process would be simplified. The genus Caldicellulosiruptor, an obligatory anaerobic and extreme thermophile can produce a diverse set of glycoside hydrolases (GHs) for deconstruction of lignocellulosic biomass. It gives potential opportunities for improving the efficiency of converting native lignocellulosic biomass to fermentable sugars. Both of the extracellular (extra-) and intracellular (intra-) enzymes of C. owensensis cultivated on corncob xylan or xylose had cellulase (including endoglucanase, cellobiohydrolase and β-glucosidase) and hemicellulase (including xylanase, xylosidase, arabinofuranosidase and acetyl xylan esterase) activities. The enzymes of C. owensensis had high ability for degrading hemicellulose of native corn stover and corncob with the conversion rates of xylan 16.7 % and araban 60.0 %. Moreover, they had remarkable synergetic function with the commercial enzyme cocktail Cellic CTec2 (Novoyzmes). When the native corn stover and corncob were respectively, sequentially hydrolyzed by the extra-enzymes of C. owensensis and CTec2, the glucan conversion rates were 31.2 and 37.9 %,which were 1.7- and 1.9-fold of each control (hydrolyzed by CTec2 alone), whereas the glucan conversion rates of the steam-exploded corn stover and corncob hydrolyzed by CTec2 alone on the same loading rate were 38.2 and 39.6 %, respectively. These results show that hydrolysis by the extra-enzyme of C. owensensis made almost the same contribution as steam-exploded pretreatment on degradation of native lignocellulosic biomass. A new process for saccharification of lignocellulosic biomass by sequential hydrolysis

  11. Bioconversion of biodiesel-derived crude glycerol into lipids and carotenoids by an oleaginous red yeast Sporidiobolus pararoseus KM281507 in an airlift bioreactor.

    Science.gov (United States)

    Manowattana, Atchara; Techapun, Charin; Watanabe, Masanori; Chaiyaso, Thanongsak

    2018-01-01

    Here we tested the bioconversion of biodiesel-derived crude glycerol by the oleaginous red yeast Sporidiobolus pararoseus KM281507 in two bioreactors types (stirred-tank and airlift). High production yields (biomass, 10.62 ± 0.21 g/L; lipids, 3.26 ± 0.13 g/L; β-carotene, 30.64 ± 0.05 mg/L; total carotenoids, 46.59 ± 0.07 mg/L) were achieved in a 3.0 L airlift bioreactor under uncontrolled pH regimes (initial pH 5.63). Under optimized conditions (6.0 vvm aeration rate; 60 ± 5% constant dissolved oxygen [DO] maintained by flushing pure oxygen [O 2 ] into the vessel; 10,000 Lux light irradiation) volumetric production in the airlift bioreactor was further increased (biomass, 19.30 ± 1.07 g/L; lipids, 6.61 ± 0.04 g/L, β-carotene, 109.75 ± 0.21 mg/L; total carotenoids 151.00 ± 2.71 mg/L). Production was also recorded at a S. pararoseus KM281507 growth rate of 0.16 ± 0.00 h -1 (lipids, 0.94 ± 0.04 g/L/d; β-carotene, 15.68 ± 0.40 mg/L/d; total carotenoids, 21.56 ± 0.20 mg/L/d). Lipids from S. pararoseus KM281507 had a high unsaturated fatty acid content, with oleic acid (C18:1) accounting for 80% of all fatty acids. This high oleic acid content makes S. pararoseus KM281507 well-suited as a third generation biodiesel feedstock. Our findings show that airlift bioreactors are suitable for bioconversion of crude glycerol into lipids and carotenoids using S. pararoseus KM281507. This approach is advantageous because of its ease of operation, cost efficiency, and low energy consumption. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  12. Effect of irradiation, as a pretreatment, on bioconversion of corn stover into protein-rich mycelial biomass of Pleurotus sajor-caju

    Energy Technology Data Exchange (ETDEWEB)

    Awafo, V.A.; Chahal, D.S.; Charbonneau, R. [Universite du Quebec (Canada). Applied Microbiology Research Center

    1995-10-01

    Application of irradiation for food preservation, for pretreatment of lignocellulosic materials for their hydrolysis and to increase the digestibility of lignocellulosic materials for rumen animals have been reported in the literature. In the present study, irradiation (100 KGy to 1.7 MGy) of corn stover as a pretreatment to make it susceptible for its bioconversion into protein-rich mycelial biomass of Pleurotus sajor-caju NRRL 18757 has been compared with that of mild alkali treatment (0.01 to 0.15 g NaOH/g corn stover), the most commonly used pretreatment. Protein synthesis increased with the increase in doses of irradiation as well as with the increase in concentration of NaOH. Combination pretreatment with NaOH and {gamma}-irradiation reduced the quantity of NaOH and doses of irradiation required to get optimum yields of protein indicating a strong synergistic effect. The highest protein content of the final product, mycelial biomass, was about 45% on dry weight basis. More than 90% utilization of corn stover polysaccharides for the synthesis of protein-rich mycelial biomass of P. sajor-caju was recorded. (author).

  13. Effect of irradiation, as a pretreatment, on bioconversion of corn stover into protein-rich mycelial biomass of Pleurotus sajor-caju

    International Nuclear Information System (INIS)

    Awafo, V.A.; Chahal, D.S.; Charbonneau, R.

    1995-01-01

    Application of irradiation for food preservation, for pretreatment of lignocellulosic materials for their hydrolysis and to increase the digestibility of lignocellulosic materials for rumen animals have been reported in the literature. In the present study, irradiation (100 KGy to 1.7 MGy) of corn stover as a pretreatment to make it susceptible for its bioconversion into protein-rich mycelial biomass of Pleurotus sajor-caju NRRL 18757 has been compared with that of mild alkali treatment (0.01 to 0.15 g NaOH/g corn stover), the most commonly used pretreatment. Protein synthesis increased with the increase in doses of irradiation as well as with the increase in concentration of NaOH. Combination pretreatment with NaOH and γ-irradiation reduced the quantity of NaOH and doses of irradiation required to get optimum yields of protein indicating a strong synergistic effect. The highest protein content of the final product, mycelial biomass, was about 45% on dry weight basis. More than 90% utilization of corn stover polysaccharides for the synthesis of protein-rich mycelial biomass of P. sajor-caju was recorded. (author)

  14. Effect of irradiation, as a pretreatment, on bioconversion of corn stover into protein-rich mycelial biomass of Pleurotus sajor-caju

    International Nuclear Information System (INIS)

    Awafo, V.A.; Chahal, D.S.; Charbonneau, R.

    1995-01-01

    Application of irradiation for food preservation, for pretreatment of lignocellulosic materials for their hydrolysis and to increase the digestibility of lignocellulosic materials for rumen animals have been reported in the literature. In the present study, irradiation (100 KGy to 1.7 MGy) of corn stover as a pretreatment to make it susceptible for its bioconversion into protein-rich mycelial biomass of Pleurotus sajor-caju NRRL 18757 has been compared with that of mied alkali treatment (0.01 to 0.15 g NaOH/g corn stover), the most commonly used pretreatment. Protein synthesis increased with the increase in doses of irradiation as well as with the increase in concentration of NaOH. Combination pretreatment with NaOH and γ-irradiation reduced the quantity of NaOH and doses of irradiation required to get optimum yields of protein indicating a strong synergistic effect. This highest protein content of the final product, mycelial biomass, was about 45% on dry weight basis. More than 90% utilization of corn stover polysaccharides for the synthesis of protein-rich mycelial biomass of P.sajor-caju was recorded. (author)

  15. Bioconversion of D-galactose to D-tagatose: continuous packed bed reaction with an immobilized thermostable L-arabinose isomerase and efficient purification by selective microbial degradation.

    Science.gov (United States)

    Liang, Min; Chen, Min; Liu, Xinying; Zhai, Yafei; Liu, Xian-wei; Zhang, Houcheng; Xiao, Min; Wang, Peng

    2012-02-01

    The continuous enzymatic conversion of D-galactose to D-tagatose with an immobilized thermostable L-arabinose isomerase in packed-bed reactor and a novel method for D-tagatose purification were studied. L-arabinose isomerase from Thermoanaerobacter mathranii (TMAI) was recombinantly overexpressed and immobilized in calcium alginate. The effects of pH and temperature on D-tagatose production reaction catalyzed by free and immobilized TMAI were investigated. The optimal condition for free enzyme was pH 8.0, 60°C, 5 mM MnCl(2). However, that for immobilized enzyme was pH 7.5, 75°C, 5 mM MnCl(2). In addition, the catalytic activity of immobilized enzyme at high temperature and low pH was significantly improved compared with free enzyme. The optimum reaction yield with immobilized TMAI increased by four percentage points to 43.9% compared with that of free TMAI. The highest productivity of 10 g/L h was achieved with the yield of 23.3%. Continuous production was performed at 70°C; after 168 h, the reaction yield was still above 30%. The resultant syrup was then incubated with Saccharomyces cerevisiae L1 cells. The selective degradation of D-galactose was achieved, obtaining D-tagatose with the purity above 95%. The established production and separation methods further potentiate the industrial production of D-tagatose via bioconversion and biopurification processes.

  16. Nitrile, amide and temperature effects on amidase-kinetics during acrylonitrile bioconversion by nitrile-hydratase/amidase in situ cascade system.

    Science.gov (United States)

    Cantarella, Laura; Gallifuoco, Alberto; Spera, Agata; Cantarella, Maria

    2013-08-01

    In this study the amidase kinetics of an in situ NHase/AMase cascade system was explored as a function of operational parameters such as temperature, substrate concentration and product formation. The results indicated that controlling amidase inactivation, during acrylonitrile bioconversion, makes it possible to recover the intermediate product of the two-step reaction in almost a pure form, without using purified enzyme. It has been demonstrated, in long-term experiments performed in continuous stirred UF-membrane bioreactors, that amidase is kinetically controlled by its proper substrate, depending on the structure, and by acrylonitrile. Using acrylamide, AMase-stability is temperature dependent (5°C, kd=0.008 h(-1); 30°C kd=0.023 h(-1)). Using benzamide, amidase is thermally stable up to 50°C and no substrate inhibition/inactivation occurs. With acrylonitrile, AMase-activity and -stability remain unchanged at concentrations <200 mM but at 200 mM, 35°C, after 70 h process, 90% irreversible inactivation occurs as no AMase-activity on benzamide revives. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Functional characterization of CYP52G3 from Aspergillus oryzae and its application for bioconversion and synthesis of hydroxyl flavanone and steroids.

    Science.gov (United States)

    Uno, Tomohide; Yanase, Takeshi; Imaishi, Hiromasa

    2017-05-01

    Aspergillus oryzae is a fungus widely used in traditional Japanese fermentation industries. Cytochrome P450 (CYP) proteins are ubiquitously distributed in nature and display a broad range of enzymatic activities. A novel CYP52 (CYP52G3) gene was found in A. oryzae. In this study, we report the functional characterization of CYP52G3. The recombinant protein was expressed heterologously in Escherichia coli, and its membrane fraction isolated. CYP52G3 showed activities for 7-ethoxycoumarin and α-naphtoflavone. Furthermore, CYP52G3 hydroxylated flavanone at the 4' and 6 position and metabolized some hydroxyl-flavanones and steroids. Bioconversion experiments indicated that CYP52G3 could convert flavanone and testosterone in a synthetic medium. The conversion rates of flavanone and testosterone at 24 H were 50% and 70%, respectively. These results support that CYP52G3 could prove a useful enzyme for the efficient production of new compounds from flavonoids and steroids. © 2016 International Union of Biochemistry and Molecular Biology, Inc.

  18. Transcriptome analysis of Pseudomonas mediterranea and P. corrugata plant pathogens during accumulation of medium-chain-length PHAs by glycerol bioconversion.

    Science.gov (United States)

    Licciardello, Grazia; Ferraro, Rosario; Russo, Marcella; Strozzi, Francesco; Catara, Antonino F; Bella, Patrizia; Catara, Vittoria

    2017-07-25

    Pseudomonas corrugata and P. mediterranea are soil inhabitant bacteria, generally living as endophytes on symptomless plants and bare soil, but also capable of causing plant diseases. They share a similar genome size and a high proteome similarity. P. corrugata produces many biomolecules which play an important role in bacterial cell survival and fitness. Both species produce different medium-chain-length PHAs (mcl-PHAs) from the bioconversion of glycerol to a transparent film in P. mediterranea and a sticky elastomer in P. corrugata. In this work, using RNA-seq we investigated the transcriptional profiles of both bacteria at the early stationary growth phase with glycerol as the carbon source. Quantitative analysis of P. mediterranea transcripts versus P. corrugata revealed that 1756 genes were differentially expressed. A total of 175 genes were significantly upregulated in P. mediterranea, while 217 were downregulated. The largest group of upregulated genes was related to transport systems and stress response, energy and central metabolism, and carbon metabolism. Expression levels of most genes coding for enzymes related to PHA biosynthesis and central metabolic pathways showed no differences or only slight variations in pyruvate metabolism. The most relevant result was the significantly increased expression in P. mediterranea of genes involved in alginate production, an important exopolysaccharide, which in other Pseudomonas spp. plays a key role as a virulence factor or in stress tolerance and shows many industrial applications. In conclusion, the results provide useful information on the co-production of mcl-PHAs and alginate from glycerol as carbon source by P. mediterranea in the design of new strategies of genetic regulation to improve the yield of bioproducts or bacterial fitness. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Isolation and Characterization of a Novel Rebaudioside M Isomer from a Bioconversion Reaction of Rebaudioside A and NMR Comparison Studies of Rebaudioside M Isolated from Stevia rebaudiana Bertoni and Stevia rebaudiana Morita

    Directory of Open Access Journals (Sweden)

    Indra Prakash

    2014-03-01

    Full Text Available A minor product, rebaudioside M2 (2, from the bioconversion reaction of rebaudioside A (4 to rebaudioside D (3, was isolated and the complete structure of the novel steviol glycoside was determined. Rebaudioside M2 (2 is considered an isomer of rebaudioside M (1 and contains a relatively rare 1→6 sugar linkage. It was isolated and characterized with NMR (1H, 13C, COSY, HSQC-DEPT, HMBC, 1D-TOCSY, and NOESY and mass spectral data. Additionally, we emphasize the importance of 1D and 2D NMR techniques when identifying complex steviol glycosides. Numerous NMR spectroscopy studies of rebaudioside M (1, rebaudioside D (3, and mixture of 1 and 3 led to the discovery that SG17 which was previously reported in literature, is a mixture of rebaudioside D (3, rebaudioside M (1, and possibly other related steviol glycosides.

  20. Fed-batch hydrolysate addition and cell separation by settling in high cell density lignocellulosic ethanol fermentations on AFEX™ corn stover in the Rapid Bioconversion with Integrated recycling Technology process.

    Science.gov (United States)

    Sarks, Cory; Jin, Mingjie; Balan, Venkatesh; Dale, Bruce E

    2017-09-01

    The Rapid Bioconversion with Integrated recycling Technology (RaBIT) process uses enzyme and yeast recycling to improve cellulosic ethanol production economics. The previous versions of the RaBIT process exhibited decreased xylose consumption using cell recycle for a variety of different micro-organisms. Process changes were tested in an attempt to eliminate the xylose consumption decrease. Three different RaBIT process changes were evaluated in this work including (1) shortening the fermentation time, (2) fed-batch hydrolysate addition, and (3) selective cell recycling using a settling method. Shorting the RaBIT fermentation process to 11 h and introducing fed-batch hydrolysate addition eliminated any xylose consumption decrease over ten fermentation cycles; otherwise, decreased xylose consumption was apparent by the third cell recycle event. However, partial removal of yeast cells during recycle was not economical when compared to recycling all yeast cells.

  1. Isolation and Characterization of a Novel Rebaudioside M Isomer from a Bioconversion Reaction of Rebaudioside A and NMR Comparison Studies of Rebaudioside M Isolated from Stevia rebaudiana Bertoni and Stevia rebaudiana Morita

    Science.gov (United States)

    Prakash, Indra; Bunders, Cynthia; Devkota, Krishna P.; Charan, Romila D.; Ramirez, Catherine; Priedemann, Christopher; Markosyan, Avetik

    2014-01-01

    A minor product, rebaudioside M2 (2), from the bioconversion reaction of rebaudioside A (4) to rebaudioside D (3), was isolated and the complete structure of the novel steviol glycoside was determined. Rebaudioside M2 (2) is considered an isomer of rebaudioside M (1) and contains a relatively rare 1→6 sugar linkage. It was isolated and characterized with NMR (1H, 13C, COSY, HSQC-DEPT, HMBC, 1D-TOCSY, and NOESY) and mass spectral data. Additionally, we emphasize the importance of 1D and 2D NMR techniques when identifying complex steviol glycosides. Numerous NMR spectroscopy studies of rebaudioside M (1), rebaudioside D (3), and mixture of 1 and 3 led to the discovery that SG17 which was previously reported in literature, is a mixture of rebaudioside D (3), rebaudioside M (1), and possibly other related steviol glycosides. PMID:24970220

  2. Survey report for fiscal 1998. Survey of creation of highly efficient renewable resources and bioconversion technologies; 1998 nendo chosa hokokusho. Kokoritsu saisei kano shigen no sosei narabini bio conversion gijutsu ni kansuru chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    A survey is conducted concerning environmentally friendly industrial technologies that utilize renewable resources, which are technologies of creating highly renewable resources and converting renewable resources by breeding industrial vegetation. In relation with the creation technologies, the state of research and development of basic technologies is surveyed, which involves the fabrication of environmental stress resisting vegetation, studies for the application of the gene expression control mechanism, introduction of multigenes and site-directed genes, etc. Concerning the respective target products expected to be produced by industrial vegetation, as much information as possible relative to genes is collected on the current state of production, metabolism in vegetation and microbials, and biosynthesis. Surveyed in relation with the bioconversion technology are the conversion of vegetation-derived polymers, construction of environmentally friendly ligno-bioprocess, conversion of sugar, production of biofuels, etc. Furthermore, the technology of treating ligneous wastes with supercritical water is surveyed, this to determine the practicality of the technology at the current stage. (NEDO)

  3. Bioconversion of cellulose to ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Hahn-Haegerdal, B; Mandenius, C F; Mattiasson, B; Nilsson, B; Axelsson, J P; Hagander, P

    1985-06-20

    Enzymatic hydrolysis of steam pretreated sallow gives highest yields of soluble sugars when hemicellulose is degraded already in the pretreatment step. The steam pretreatment equipment is rebuilt so that 75 g (dry matter) material instead of 7 g can be treated each time. The cellulose production has been increased 123% by the utilization of aqueous two-phase systems as compared to regular growth medium. The cellulase activity per gram of cellulose has been increased from 42 FPU in regular growth medium to 156 FPU in aqueous two-phase systems. Crude dextran can be used for enzyme production. Enzyme recovery up to 75% has been achieved by combining aqueous two-phase technique with membrane technique. Using the enzyme glucose isomerase in combination with S. cerevisiae theoretical yields in pentose fermentations have been achieved, with a product concentration of 60 g/L and a productivity of 2 g/L x h. Yeast and enzyme can be recirculated using membrane technique. Computer simulation shows that the rate equation for enzymatic hydrolysis with respect to inhibiting sugar concentrations can be used to interpolate with respect to sugar concentrations. Computer simulations show that hydrolysis experiments should focus on high substrate concentrations (>10%) using fed-batch technique and enzyme concentrations in the range of 2-8% in relation to substrate dry matter. The combined 'flow injection analysis', FIA, and enzyme reactor probe has been adapted to enzymatic saccarifications of sodium hydroxide pretreated sallow. The gas membrane sensor for ethanol has been utilized in simultaneous saccharification and fermentation of sodium hydroxide pretreated sallow. A literature study concerning pervaporation for ethanol up-grading has been made.(Author).

  4. Environmental aspects of bioconversion processes

    International Nuclear Information System (INIS)

    Klein, J.; Pfeifer, F.; Schacht, S.; Sinder, C.

    1997-01-01

    Investigations were carried out on selection, adaptation and validation of bioassays suited for a sensitive and reproducible valuation of coal relevant products. Bioassays with organisms representing different trophic levels like bacteria, daphnia and algae were used for determination of ecotoxicological/toxicological effects. The results show the suitability of these bioassays for the valuation of ecotoxicological effects of coal-relevant substances and different model compounds similar to microbial transformation/conversion products of coal. 5 refs., 3 figs., 5 tabs

  5. Bioconversion of α-linolenic acid to n-3 LCPUFA and expression of PPAR-alpha, acyl Coenzyme A oxidase 1 and carnitine acyl transferase I are incremented after feeding rats with α-linolenic acid-rich oils.

    Science.gov (United States)

    González-Mañán, Daniel; Tapia, Gladys; Gormaz, Juan Guillermo; D'Espessailles, Amanda; Espinosa, Alejandra; Masson, Lilia; Varela, Patricia; Valenzuela, Alfonso; Valenzuela, Rodrigo

    2012-07-01

    High dietary intake of n-6 fatty acids in relation to n-3 fatty acids may generate health disorders, such as cardiovascular and other chronic diseases. Fish consumption rich in n-3 fatty acids is low in Latin America, it being necessary to seek other alternatives to provide α-linolenic acid (ALA), precursor of n-3 LCPUFA (EPA and DHA). Two innovative oils were assayed, chia (Salvia hispanica) and rosa mosqueta (Rosa rubiginosa). This study evaluated hepatic bioconversion of ALA to EPA and DHA, expression of PPAR-α, acyl-Coenzyme A oxidase 1 (ACOX1) and carnitine acyltransferase I (CAT-I), and accumulation of EPA and DHA in plasma and adipose tissue in Sprague-Dawley rats. Three experimental groups were fed 21 days: sunflower oil (SFO, control); chia oil (CO); rosa mosqueta oil (RMO). Fatty acid composition of total lipids and phospholipids from plasma, hepatic and adipose tissue was assessed by gas-liquid chromatography and TLC. Expression of PPAR-α (RT-PCR) and ACOX1 and CAT-I (Western blot). CO and RMO increased plasma, hepatic and adipose tissue levels of ALA, EPA and DHA and decreased n-6:n-3 ratio compared to SFO (p oil.

  6. INDUSTRIAL WASTE BIOCONVERSION INTO SURFACTANTS BY Rhodococcus erythropolis ІMV Ас-5017, Acinetobacter calcoaceticus ІMV В-7241 and Nocardia vaccinii ІMV В-7405

    Directory of Open Access Journals (Sweden)

    T. P. Pirog

    2017-04-01

    pollution in water (3−6 g/l and soil (20 g/kg after 20 days was 82−92%. Bioconversion of industrial waste into surfactants for environmental technology allows recycling toxic waste, reducing costs of microbial surfactants and provides double effect of environmental purification, which is achieved in the production and use of microbial surfactants.

  7. Evaluation of the hepatic bioconversion of α-linolenic acid (ALA to eicosapentaenoic acid (EPA and docosahexaenoic acid (DHA in rats fed with oils from chia (Salvia hispánica or rosa mosqueta (Rosa rubiginosa

    Directory of Open Access Journals (Sweden)

    Tapia O., G.

    2012-03-01

    Full Text Available The high dietary intake of n-6 fatty acids in relation to n-3 fatty acids generates health disorders, such as cardiovascular diseases, inflammatory diseases and other chronic diseases. The consumption of fish, which is rich in n-3 fatty acids, is low in Latin America and it is necessary to seek other alternatives, such as chia oil (CO or rosa mosqueta oil (RMO, which are rich in α-linolenic acid (ALA, the precursor of the n -3 fatty acids, eicosapentaenoic acid (EPA and docosahexaenoic acid (DHA. This study evaluates the hepatic bioconversion of ALA to EPA and DHA and the damage to the liver (histology and transaminase in Sprague- Dawley rats fed different vegetable oils. Four experimental groups (n = 9 animals each group were fed the following dietary supplements for 21 days: a sunflower oil (SFO, b RMO, c CO d olive oil with fish oil added (EPA and DHA (OO/FO. RMO and CO increased the hepatic levels of ALA, EPA and DHA and decreased the n-6/n-3 ratio compared to SFO (p El elevado aporte en la dieta de ácidos grasos omega- 6, en relación a los ácidos grasos omega-3, genera alteraciones de la salud cardiovascular, inflamación y otras patologías crónicas no transmisibles. Por otro lado, el pescado rico en ácidos grasos omega-3 es de bajo consumo en Latinoamérica, siendo necesario buscar otras alternativas de aporte de ácidos grasos omega-3, como lo son el aceite de chía (CO o el de rosa mosqueta (RMO, ricos en ácido α-linolénico (ALA, que es el precursor de los ácidos grasos omega-3, eicosapentaenoico (EPA y docosahexaenoico (DHA. Este trabajo evaluó en forma preliminar la bioconversión hepática del ALA en EPA y DHA y el daño hepático (histología y transaminasas en ratas Sprague-Dawley alimentadas con diferentes aceites vegetales. Se conformaron cuatro grupos experimentales (n = 9 animales por grupo que recibieron durante 21 días: a aceite de girasol (SFO; b RMO, c CO y d aceite de oliva adicionado de aceite de pescado (EPA

  8. Bioconversion of petroleum hydrocarbons in soil using apple filter cake Bioconversão de hidrocarbonetos de petróleo no solo pelo uso de bagaço de maçã

    Directory of Open Access Journals (Sweden)

    M. Cecilia Medaura

    2008-09-01

    Full Text Available The aim of this study was to investigate the feasibility of using apple filter cake, a fruit-processing waste to enhance the bioremediation of petroleum contaminated soil. A rotating barrel system was used to study the bioconversion of the xenobiotic compound by natural occurring microbial population. The soil had been accidentally polluted with a total petroleum hydrocarbon concentration of 41,000 ppm. Although this global value was maintained during the process, microbial intervention was evidenced through transformation of the petroleum fractions. Thus, fractions that represent a risk for the environment (GRO, Gasoline Range Organics i.e., C6 to C10-12; DRO, Diesel Range Organics i.e., C8-12 to C24-26 and RRO, Residual Range Organics i.e., C25 to C35 were significantly reduced, from 2.95% to 1.39%. On the contrary, heavier weight fraction from C35 plus other organics increased in value from 1.15% to 3.00%. The noticeable diminution of low molecular weight hydrocarbons content and hence environmental risk by the process plus the improvement of the physical characteristics of the soil, are promising results with regard to future application at large scale.O objetivo deste estudo foi investigara viabilidade de aplicação de bagaço de maçã, um resíduo do processamento de frutas, para melhorar a biorremediação de solo contaminado com petróleo. Para estudar a bioconversão de compostos xenobióticos pela população microbiana naturalmente presente empregou-se um sistema de barril rotativo. O solo havia sido acidentalmente contaminado com um total de hidrocarbonetos de petróleo na concentração de 41.000 ppm. Embora esse valor tenha se mantido durante o processo, a intervenção microbiana ficou evidenciada através da transformação de frações do petróleo. Assim, as frações de risco para o meio ambiente (GRO, Gasoline Range Organics, i.e., C6 a C10-12; DRO, Diesel Ramge Organics, i.e. C8-12 a C24-26 e RRO, Residual Range Organics

  9. Evaluasi Perlakuan Pendahuluan Menggunakan Kalsium Hidroksida untuk Biokonversi Jerami Padi Menjadi L-Asam Laktat oleh Rhizopus oryzae AT3 (Evaluation of Lime Pretreatment for Bioconversion of Rice Straw to L-Lactic Acid by Rhizopus Oryzae AT3

    Directory of Open Access Journals (Sweden)

    Dhina Aprilia Nurani Widyahapsari

    2016-12-01

    Full Text Available L-lactic acid can be used as a precursor of polylactic acid (PLA. PLA is a biodegradable biomaterial commonly used for biodegradable plastics. Lactic acid can be produced from lignocelluloses materials such as rice straw. Rice straw is composed of cellulose and hemicellulose that can be hydrolyzed to fermentable sugar by cellulolytic and hemicellulolytic enzymes then converted to L-lactic acid by Rhizopus oryzae. As most cellulose and hemicellulose present in lignocellulose biomass are not readily accessible for these enzyme, pretreatment is required to alter the structure of lignocellulose substrates. This research aimed to investigate the effect of lime pretreatment on rice straw bioconversion to L-lactic acid by Rhizopus oryzae AT3. Rice straw was pretreated with lime (Ca(OH2 at 85 °C for 16 hours. Unpretreated and pretreated rice straw were hydrolyzed using crude enzyme that produced by Trichoderma reesei Pk1J2. Enzyme production was carried out by solid state fermentation using rice straw and rice brand as substrate. Enzymatic hydrolysis was carried out in flasks. Each flask was added with unpretreated or pretreated rice straw, buffer citrate solution and crude enzyme then hydrolyzed for 0-96 hours. Hydrolysate was fermented by Rhizopus oryzae AT3 for 0-6 days by using adsorbed carrier solid-state fermentation method with polyurethane foam as inert support material. Lime pretreatment at 85 °C for 16 hour led to significant solubilisation of lignin and hemicellulose. It involved lignocellulose structure modified that enhance enzymatic hydrolysis and resulted higher reducing sugars than unpretreated rice straw. The high reducing sugars was not related to high lactic acid yields. Fermentation of pretreated rice straw hydrolysate by Rhizopus oryzae AT3 did not only produce L-lactic acid but also other compound. On the other hand, fermentation of unpretreated rice straw hydrolysate only produced L-lactic acid.   ABSTRAK Polimerisasi asam

  10. Biodiesel byproduct bioconversion to rhamnolipids: Upstream aspects.

    Science.gov (United States)

    Salazar-Bryam, Ana Maria; Lovaglio, Roberta Barros; Contiero, Jonas

    2017-06-01

    This study focused on two important aspects of the upstream process: the appropriate use of crude glycerol as a low-cost carbon source, and strain selection. The effect of different crude glycerol concentrations on rhamnolipid biosynthesis by two Pseudomonas aeruginosa strains (wild type LBI and mutant LBI 2A1) was studied. Finally, the synthesized rhamnolipids were characterized by mass spectrometry. When both strains were compared, 50 g/L was the most favorable concentration for both, but P. aeruginosa LBI 2A1 showed an increase in rhamnolipid production (2.55 g/L) of 192% over wild type (1.3 g/L). The higher rhamnolipid production could be related to a possible mechanism developed after the mutation process at high antibiotic concentrations. Mass spectrometry confirmed the glycolipid nature of the produced biosurfactant, and the homologue composition showed a wide mixture of mono and di-rhamnolipids. These results show that high glycerol concentrations can inhibit microbial metabolism, due to osmotic stress, leading to a better understanding of glycerol metabolism towards its optimization in fermentation media. Since P. aeruginosa LBI 2A1 showed higher conversion yields than P. aeruginosa LBI, the use of a mutant strain associated with a low cost carbon source might improve biosurfactant biosynthesis, therefore yielding an important upstream improvement.

  11. Biodiesel byproduct bioconversion to rhamnolipids: Upstream aspects

    OpenAIRE

    Salazar-Bryam, Ana Maria; Lovaglio, Roberta Barros; Contiero, Jonas

    2017-01-01

    This study focused on two important aspects of the upstream process: the appropriate use of crude glycerol as a low-cost carbon source, and strain selection. The effect of different crude glycerol concentrations on rhamnolipid biosynthesis by two Pseudomonas aeruginosa strains (wild type LBI and mutant LBI 2A1) was studied. Finally, the synthesized rhamnolipids were characterized by mass spectrometry. When both strains were compared, 50 g/L was the most favorable concentration for both, but P...

  12. Biodiesel byproduct bioconversion to rhamnolipids: Upstream aspects

    Directory of Open Access Journals (Sweden)

    Ana Maria Salazar-Bryam

    2017-06-01

    Full Text Available This study focused on two important aspects of the upstream process: the appropriate use of crude glycerol as a low-cost carbon source, and strain selection. The effect of different crude glycerol concentrations on rhamnolipid biosynthesis by two Pseudomonas aeruginosa strains (wild type LBI and mutant LBI 2A1 was studied. Finally, the synthesized rhamnolipids were characterized by mass spectrometry. When both strains were compared, 50 g/L was the most favorable concentration for both, but P. aeruginosa LBI 2A1 showed an increase in rhamnolipid production (2.55 g/L of 192% over wild type (1.3 g/L. The higher rhamnolipid production could be related to a possible mechanism developed after the mutation process at high antibiotic concentrations. Mass spectrometry confirmed the glycolipid nature of the produced biosurfactant, and the homologue composition showed a wide mixture of mono and di-rhamnolipids. These results show that high glycerol concentrations can inhibit microbial metabolism, due to osmotic stress, leading to a better understanding of glycerol metabolism towards its optimization in fermentation media. Since P. aeruginosa LBI 2A1 showed higher conversion yields than P. aeruginosa LBI, the use of a mutant strain associated with a low cost carbon source might improve biosurfactant biosynthesis, therefore yielding an important upstream improvement. Keywords: Biotechnology, Microbiology

  13. SMART BIOCONVERSION OF PELT WASTE FROM TANNERIES

    Directory of Open Access Journals (Sweden)

    ZAINESCU Gabriel

    2017-05-01

    Full Text Available The area of interest is the synthesis and study of properties of new types of hydrogels made from pelt waste, in order to recover waste from tanneries. Leather processing in tanneries results in about 500-600 kg of pelt waste from a ton of raw hides. These hydrogels are made using smart processes in order to then be applied in agriculture, for preservation of water in the soil or for controlled release of fertilizers, pesticides but also for the development of additivated agricultural film biodegradable over time (between 1 month and 6 months. Hydrogels that are based on biopolymers, compared with hydrogels based on synthetic polymers, have the advantage of biodegradability, biocompatibility, and a low level of toxicity. The paper presents the production of biodegradable polymer mixtures obtained from hydrolysis and enrichment of the resulting hydrolysate with phosphorus and potassium. Hydrogels with collagenous structure are tested using a high-performance instrumental analysis system (FT-IR-ATR, UV-VIS-NIR, SEM, EDAX, etc. The paper presents an experimental model for obtaining hydrogels with collagenous structure from pelt waste resulting from the liming process.

  14. Enzymology of lignocellulose bioconversion by Streptomyces viridosporus

    International Nuclear Information System (INIS)

    Ramachandra, M.

    1989-01-01

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

  15. Bioconversion of Capsaicin by Aspergillus oryzae.

    Science.gov (United States)

    Lee, Minji; Cho, Jeong-Yong; Lee, Yu Geon; Lee, Hyoung Jae; Lim, Seong-Il; Park, So-Lim; Moon, Jae-Hak

    2015-07-08

    This study identified metabolites of capsaicin bioconverted by Aspergillus oryzae, which is generally used for mass production of gochujang prepared by fermenting red pepper powder in Korea. A. oryzae was incubated with capsaicin in potato dextrose broth. Capsaicin decreased depending on the incubation period, but new metabolites increased. Five capsaicin metabolites purified from the ethyl acetate fraction of the capsaicin culture were identified as N-vanillylcarbamoylbutyric acid, N-vanillyl-9-hydroxy-8-methyloctanamide, ω-hydroxycapsaicin, 8-methyl-N-vanillylcarbamoyl-6(E)-octenoic acid, and 2-methyl-N-vanillylcarbamoyl-6(Z)-octenoic acid by nuclear magnetic resonance (NMR) and mass spectrometry (MS). The capsaicin metabolites in gochujang were confirmed and quantitated by selective multiple reaction monitoring detection after liquid chromatography electrospray ionization MS using the isolated compounds as external standards. On the basis of the structures of the capsaicin metabolites, it is proposed that capsaicin metabolites were converted by A. oryzae by ω-hydroxylation, alcohol oxidation, hydrogenation, isomerization, and α- and/or β-oxidation.

  16. Lignocellulose biotechnology: issues of bioconversion and enzyme ...

    African Journals Online (AJOL)

    Admin

    Water, which is essential for microbial activities, is present in an absorbed or in complexed-form with the solid matrix and the substrate (Cannel and Moo-Young,. 1980). These cultivation conditions are especially suitable for the growth of fungi, known to grow at relatively low water activities. As the microorganisms in.

  17. Bioconversion of renewable resources into lactic acid: an industrial view.

    Science.gov (United States)

    Yadav, A K; Chaudhari, A B; Kothari, R M

    2011-03-01

    Lactic acid, an anaerobic product of glycolysis, can be theoretically produced by synthetic route; however, it is commercially produced by homo-fermentative batch mode of operations. Factors affecting its production and strategies improving it are considered while devising an optimized protocol. Although a hetero-fermentative mode of production exists, it is rarely used for commercial production. Attempts to use Rhizopus sp. for lactic acid production through either hetero-fermentative or thermophilic conditions were not economical. Since almost 70% of the cost of its production is accounted by raw materials, R & D efforts are still focused to find economically attractive agri-products to serve as sources of carbon and complex nitrogen inputs to meet fastidious nutrient needs for microbial growth and lactic acid production. Therefore, need exists for using multi-pronged strategies for higher productivity. Its present production and consumption scenario is examined. Its optically active isomers and chemical structure permit its use for the production of several industrially important chemicals, health products (probiotics), food preservatives, and bio-plastics. In addition, its salts and esters appear to have a variety of applications.

  18. Bioconversion of sago residue into value added products

    African Journals Online (AJOL)

    USER

    2010-04-05

    Apr 5, 2010 ... In Sarawak, East Malaysia, agro-residues from sago starch processing industries are ... conversion to animal food or fuel ethanol (Species. Profiles for Pacific Island ..... serious contamination of the rivers. Based on study by.

  19. Bioconversion of palm kernel meal for aquaculture: Experiences ...

    African Journals Online (AJOL)

    SERVER

    2008-04-17

    Apr 17, 2008 ... es as well as food supplies have existed traditionally with coastal regions of Liberia and ..... Contamination of palm kernel meal with Aspergillus ... Sciences, Universiti Sains Malaysia, Penang 11800, Malaysia. Aquacult. Res.

  20. The bioconversion process of deoxypodophyllotoxin with Linum flavum cell cultures

    NARCIS (Netherlands)

    Koulman, A; Beekman, A.C; Pras, N.; Quax, Wim

    2003-01-01

    The in vitro cell suspension culture of Linum flavum is able to convert high amounts of the 2,7'-cyclolignan deoxypodophyllotoxin into 6-methoxypodophyllotoxin 7-O-glucoside. We studied this conversion in detail by monitoring the intermediates and side-products after feeding different concentrations

  1. Renewable biofuels bioconversion of lignocellulosic biomass by microbial community

    CERN Document Server

    Rana, Vandana

    2017-01-01

    This book offers a complete introduction for novices to understand key concepts of biocatalysis and how to produce in-house enzymes that can be used for low-cost biofuels production. The authors discuss the challenges involved in the commercialization of the biofuel industry, given the expense of commercial enzymes used for lignocellulose conversion. They describe the limitations in the process, such as complexity of lignocellulose structure, different microbial communities’ actions and interactions for degrading the recalcitrant structure of lignocellulosic materials, hydrolysis mechanism and potential for bio refinery. Readers will gain understanding of the key concepts of microbial catalysis of lignocellulosic biomass, process complexities and selection of microbes for catalysis or genetic engineering to improve the production of bioethanol or biofuel.

  2. Bioconversion of crude glycerol feedstocks into ethanol by Pachysolen tannophilus

    DEFF Research Database (Denmark)

    Liu, Xiaoying; Jensen, Peter Ruhdal; Workman, Mhairi

    2012-01-01

    Glycerol, the by-product of biodiesel production, is considered as a waste by biodiesel producers. This study demonstrated the potential of utilising the glycerol surplus through conversion to ethanol by the yeast Pachysolen tannophilus (CBS4044). This study demonstrates a robust bioprocess which...... was not sensitive to the batch variability in crude glycerol dependent on raw materials used for biodiesel production. The oxygen transfer rate (OTR) was a key factor for ethanol production, with lower OTR having a positive effect on ethanol production. The highest ethanol production was 17.5 g/L on 5% (v/v) crude...... glycerol, corresponding to 56% of the theoretical yield. A staged batch process achieved 28.1 g/L ethanol, the maximum achieved so far for conversion of glycerol to ethanol in a microbial bioprocess. The fermentation physiology has been investigated as a means to designing a competitive bioethanol...

  3. Bioconversion of lignocellulosic biomass to xylitol: An overview.

    Science.gov (United States)

    Venkateswar Rao, Linga; Goli, Jyosthna Khanna; Gentela, Jahnavi; Koti, Sravanthi

    2016-08-01

    Lignocellulosic wastes include agricultural and forest residues which are most promising alternative energy sources and serve as potential low cost raw materials that can be exploited to produce xylitol. The strong physical and chemical construction of lignocelluloses is a major constraint for the recovery of xylose. The large scale production of xylitol is attained by nickel catalyzed chemical process that is based on xylose hydrogenation, that requires purified xylose as raw substrate and the process requires high temperature and pressure that remains to be cost intensive and energy consuming. Therefore, there is a necessity to develop an integrated process for biotechnological conversion of lignocelluloses to xylitol and make the process economical. The present review confers about the pretreatment strategies that facilitate cellulose and hemicellulose acquiescent for hydrolysis. There is also an emphasis on various detoxification and fermentation methodologies including genetic engineering strategies for the efficient conversion of xylose to xylitol. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Bioconversion of sago residue into value added products | Awg ...

    African Journals Online (AJOL)

    ... value added products. DS Awg-Adeni, S Abd-Aziz, K Bujang, MA Hassan ... sago processing mills. This review focuses on the developments in processes and products for the value addition of sago residues through biotechnological means.

  5. Bioconversion of rape straw into a nutritionally enriched substrate by ...

    African Journals Online (AJOL)

    Jane

    2011-06-22

    Jun 22, 2011 ... rape straw substrate and the secretion of ligninolytic enzyme system including laccase (Lac), manganese ... results are mostly fields burning or natural degradation. The former ... Microbial conversion, especially fungal bio- conversion ... out at 27°C in plastic bags containing 200 g of lignocellulosic substrate ...

  6. Bioconversion of paper sludge with low cellulosic content to ethanol ...

    African Journals Online (AJOL)

    The purpose of the present work was to evaluate the possibility of converting paper sludge into ethanol using xylose-fermenting yeast SHY07-1 in separate hydrolysis and fermentation. In the enzymatic hydrolysis step, sludge on 2% (w/v, expressed in terms of total carbohydrate mass) substrate consistency was incubated ...

  7. Bioconversion of corncob to hydrogen using anaerobic mixed microflora

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Chunmei [Department of Chemistry, Zhengzhou University, Daxue Road, Zhengzhou 450052 (China); Biotechnology Department, Zhengzhou College of Animal Husbandry Engineering, Zhengzhou 450011 (China); Zhang, Shufang; Fan, Yaoting; Hou, Hongwei [Department of Chemistry, Zhengzhou University, Daxue Road, Zhengzhou 450052 (China)

    2010-04-15

    Biohydrogen production from corncob using natural anaerobic microflora was reported for the first time. The optimum pretreatment condition for the corncob was determined to be 100 C, 30 min, and 1% HCl (w/w). The maximum hydrogen yield of 107.9 ml/g-TVS and hydrogen production rate of 4.20 ml/g-TVS h{sup -1} was obtained under the condition of 10 g/l substrate concentration and initial pH 8.0. Butyrate and acetate were the dominant metabolic by-products of hydrogen fermentation. Chemical composition analysis, Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) were used to study the mechanism of degrading corncob for hydrogen production. The amorphous domains of cellulose and hemicellulose were hydrolyzed into fermentable saccharides through acid pretreatment and the microorganisms had a devastating effect on the crystallinity of the cellulose. The hydrogen yield from pretreated corncob was much higher than from raw corncob. Therefore, the acid pretreatment played a crucial role on hydrogen production from corncob. (author)

  8. Bioconversion process of rice straw by thermotolerant cellulolytic ...

    African Journals Online (AJOL)

    Administrator

    2011-09-26

    state fermentation for bioethanol production is a focus of current attention. ... Optimization of fermentation conditions showed highest cellulolytic enzymes ... using dilute acid pretreated rice straw hydrolysate with initial soluble ...

  9. Photoproduction of hydrogen - A potential system of solar energy bioconversion

    Energy Technology Data Exchange (ETDEWEB)

    Das, V S.R.

    1979-10-01

    The photoproduction of hydrogen from water utilizing the photosynthetic capacity of green plants is discussed as a possible means of solar energy conversion. Advantages of the biological production of H/sub 2/ over various physical and chemical processes are pointed out, and the system used for the production of hydrogen by biological agents, which comprises the photosynthetic electron transport chain, ferredoxin and hydrogenase, is examined in detail. The various types of biological hydrogen production systems in bacteria, algae, symbiotic systems and isolated chloroplast-ferredoxin-hydrogenase systems are reviewed. The limitations and the scope for further improvement of the promising symbiotic Azolli-Anabena azollae and chloroplast-ferredoxin-hydrogenase are discussed, and it is concluded that future research should concern itself with the identification of the environmental conditions that would maximize solar energy conversion efficiency, the elimination of the oxygen inhibition of biological hydrogen production, and the definition of the metabolic state for the maximal production of hydrogen.

  10. Bioconversion of cellulose into electrical energy in microbial fuel cells

    Science.gov (United States)

    Rismani-Yazdi, Hamid

    In microbial fuel cells (MFCs), bacteria generate electricity by mediating the oxidation of organic compounds and transferring the resulting electrons to an anode electrode. The first objective of this study was to test the possibility of generating electricity with rumen microorganisms as biocatalysts and cellulose as the electron donor in two-compartment MFCs. Maximum power density reached 55 mW/m2 (1.5 mA, 313 mV) with cellulose as the electron donor. Cellulose hydrolysis and electrode reduction were shown to support the production of current. The electrical current was sustained for over two months with periodic cellulose addition. Clarified rumen fluid and a soluble carbohydrate mixture, serving as the electron donors, could also sustain power output. The second objective was to analyze the composition of the bacterial communities enriched in the cellulose-fed MFCs. Denaturing gradient gel electrophoresis of PCR amplified 16S rRNA genes revealed that the microbial communities differed when different substrates were used in the MFCs. The anode-attached and the suspended consortia were shown to be different within the same MFC. Cloning and analysis of 16S rRNA gene sequences indicated that the most predominant bacteria in the anode-attached consortia were related to Clostridium spp., while Comamonas spp. was abundant in the suspended consortia. The external resistance affects the characteristic outputs of MFCs by controlling the flow of electrons from the anode to the cathode. The third objective of this study was to determine the effect of various external resistances on power output and coulombic efficiency of cellulose-fed MFCs. Four external resistances (20, 249, 480, and 1000 ohms) were tested with a systematic approach of operating parallel MFCs independently at constant circuit loads for three months. A maximum power density of 66 mWm-2 was achieved by MFCs with 20 ohms circuit load, while MFCs with 249, 480 and1000 ohms external resistances produced 57.5, 53 and 47 mWm-2, respectively. The anode potential varied under the different circuit loads employed. Higher coulombic efficiencies were achieved in MFCs with lower external resistance. The effect of different external resistances on the bacterial diversity and metabolism in cellulose-fed MFCs was investigated as the fourth objective. DGGE analysis of partial 16S rRNA genes showed clear differences between the planktonic and the anode-attached populations at various external resistances. Cellulose degradation was complete (anaerobic degradation of cellulose was accompanied by production of acetic, propionic, butyric, isobutyric, valeric, isovaleric, and lactic acids, with acetic acid being predominant. The profile of metabolites was different among the MFCs. The concentrations of SCFA were higher in MFCs with larger external resistance. High levels of SCFA indicated that fermentative metabolism dominated over anaerobic respiration, resulting in relatively low coulombic efficiencies. The accumulation of SCFA at higher circuit resistances corresponded to lower power outputs. Methanogenesis shifts the flow of electrons available from the substrate away from electricity generation in MFCs. The fifth objective of this research was to assess the influence of methane formation on the performance of cellulose-fed MFCs under long-term operation. A maximum volumetric power density of 3.5 W m-3 was achieved in R20O MFCs, which was three times greater than that obtained with R100O MFCs (1.03 W m-3). The diversity of methanogens in cellulose-fed MFCs was also characterized. It was shown that the suppression of methanogenesis was accompanied by a decrease in the diversity of methanogens and changes in the concentration of SCFA, as revealed by DGGE analysis of PCR-amplified 16S rRNA genes and HPLC analysis, respectively. Analysis of partial 16S rRNA gene Sequences indicated that the most predominant methanogens were related to the family Methanobacteriaceae . The results demonstrate that electricity can be generated from cellulose by exploiting rumen microorganisms as biocatalysts. Results suggest that oxidation of metabolites with the anode as an electron sink was a rate limiting step in the conversion of cellulose to electricity in MFCs. This study also demonstrates that the size of external resistance significantly affects the bacterial diversity and characteristic output of MFCs. Thus the external resistance may be a useful tool to control microbial communities and consequently enhance performance of MFCs. Furthermore, this study shows that methanogenesis competes with electricity generation at the early stages of MFC operation but operating conditions suppress methanogenic activity over time. An improved understanding of the microbial communities, interspecies interactions and processes involved in electricity generation is essential to effectively design and control cellulose-fed MFCs for enhanced performance. In addition, technical and biological optimization is needed to maximize power output of these systems.

  11. Bioconversion of rice straw as animal feed ingredient through solid state fermentation

    International Nuclear Information System (INIS)

    Mohamad Hanif Mohamad Jamil; Sepiah Muid

    1998-01-01

    Work was conducted to establish procedures and techniques to utilise microorganisms, particularly basidiomycetes, for solid fermentation of rice by-products. The purpose of the study was to determine the potential of biologically processed rice by-products as ingredients of feed formula for selected livestock. Fungal organisms Auriculariapolytrichia, Lentimus connatus, L. edodes, Pleurotus cystidiosus, P. florida, P. sajor-caju and Volvariella volvacea respectively were inoculated on sterilised rice straw and the mycelium produced were cultured for periods of 3-4 weeks by which time the straw was fully enmeshed with mycelia. Proximate analysis of the finished products gave increases of 93-172 % crude protein and reduction of 31-54 % crude fibre on comparison with untreated rice straw. Amino acid analysis showed general increases for solid fermented rice straw (SFRS) which were comparatively close to amino acid values of conventional feed ingredients such as wheat, corn, sorghum and barley. Solid fermented rice straw was also tested as an ingredient in the formulation of rations for broiler chickens. Feeding trials on poultry indicated a maximum substitution of 50% maize with SFRS in feed rations was possible to attain acceptable growth of chickens to an average live final weight of 1.8 - 2.0 kg. per chicken at age 7 weeks. From studies undertaken, it was observed that the cellulolytic straw could be developed as a potential feed material for livestock through solid fermentation with microorganisms. From the research results, the use of solid fermented rice straw as an alternative ingredient in animal feeds may be one way in reducing reliance on feed imports and at the same time controlling environmental pollution. (Author)

  12. Process development studies on the bioconversion of cellulose and production of ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Wilke, C.R.; Blanch, H.W.

    1978-12-01

    Progress is reported in the following areas: raw materials and process evaluation, enzyme fermentation studies, ethanol fermentation studies, hydrolysis reactor development, and utilization of hemi-cellulose sugars. (MHR)

  13. Process development studies on the bioconversion of cellulose and production of ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Wilke, C.R.

    1978-02-01

    Progress is reported on studies on the NO--O/sub 2/ pretreatment of wheat straw prior to enzymatic hydrolysis. Studies of the conversion of xylose to ethanol by Fusarium oxysporum were continued. Progress is also reported on pilot plant process development and design studies on continuous cellulase production, enzyme recovery, batch cellulase enzyme production from Trichoderma viride, and kinetic modelling of the enzymatic hydrolysis of 5 percent newsprint. (JGB)

  14. Pilot plant studies of the bioconversion of cellulose and production of ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Wilke, C.R.

    1977-09-30

    Work for the period July 1 to September 30, 1977 is summarized briefly. Results of the following studies are reported: analysis and evaluation of potential raw materials--chemical analysis of the Kudzu plant and effect of NO/sub x/ pretreatments on the hydrolysis of wheat straw; utilization of hemicellulose sugars; process design and economic studies--hydrolysis process and ethanol fermentation; pilot plant process development and design studies--enhanced cellulase production and continuous hydrolysis. (JGB)

  15. Bioconversion of mixed volatile fatty acids into microbial lipids by Cryptococcus curvatus ATCC 20509.

    Science.gov (United States)

    Liu, Jia; Yuan, Ming; Liu, Jia-Nan; Huang, Xiang-Feng

    2017-10-01

    The oleaginous yeast Cryptococcus curvatus ATCC 20509 can use 5-40g/L of acetic, propionic, or butyric acid as sole carbon source to produce lipids. High concentrations (30g/L) of mixed volatile fatty acids (VFAs) were used to cultivate C. curvatus to explore the effects of different ratios of mixed VFAs on lipid production and composition. When mixed VFAs (VFA ratio was 15:5:10) were used as carbon sources, the highest cell mass and lipid concentration were 8.68g/L and 4.93g/L, respectively, which were significantly higher than those when 30g/L of acetic acid was used as sole carbon source. The highest content and yield of odd-numbered fatty acids were 45.1% (VFA ratio was 0:15:15) and 1.62g/L (VFA ratio was 5:15:10), respectively. These results indicate that adjusting the composition ratios of mixed VFAs effectively improves microbial lipid synthesis and the yield of odd-numbered fatty acids. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Enhancing the Bioconversion of Azelaic Acid to Its Derivatives by Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Nurshafira Khairudin

    2018-02-01

    Full Text Available Azelaic acid (AzA and its derivatives have been known to be effective in the treatment of acne and various cutaneous hyperpigmentary disorders. The esterification of azelaic acid with lauryl alcohol (LA to produce dilaurylazelate using immobilized lipase B from Candida antarctica (Novozym 435 is reported. Response surface methodology was selected to optimize the reaction conditions. A well-fitting quadratic polynomial regression model for the acid conversion was established with regards to several parameters, including reaction time and temperature, enzyme amount, and substrate molar ratios. The regression equation obtained by the central composite design of RSM predicted that the optimal reaction conditions included a reaction time of 360 min, 0.14 g of enzyme, a reaction temperature of 46 °C, and a molar ratio of substrates of 1:4.1. The results from the model were in good agreement with the experimental data and were within the experimental range (R2 of 0.9732.The inhibition zone can be seen at dilaurylazelate ester with diameter 9.0±0.1 mm activities against Staphylococcus epidermidis S273. The normal fibroblasts cell line (3T3 was used to assess the cytotoxicity activity of AzA and AzA derivative, which is dilaurylazelate ester. The comparison of the IC50 (50% inhibition of cell viability value for AzA and AzA derivative was demonstrated. The IC50 value for AzA was 85.28 μg/mL, whereas the IC50 value for AzA derivative was more than 100 μg/mL. The 3T3 cell was still able to survive without any sign of toxicity from the AzA derivative; thus, it was proven to be non-toxic in this MTT assay when compared with AzA.

  17. Bioconversion of biodiesel refinery waste in the bioemulsifier by Trichosporon mycotoxinivorans CLA2

    Directory of Open Access Journals (Sweden)

    de Souza Monteiro Andrea

    2012-05-01

    Full Text Available Abstract Background The microbial bioemulsifiers was surface active compounds, are more effective in stabilizing oil-in-water emulsions. The yeasts have been isolated to produce bioemulsifiers from vegetable oils and industrial wastes. Results Trichosporon mycotoxinivorans CLA2 is bioemulsifier-producing yeast strain isolated from effluents of the dairy industry, with ability to emulsify different hydrophobic substrates. Bioemulsifier production (mg/L and the emulsifying activity (E24 of this strain were optimized by response surface methodology using mineral minimal medium containing refinery waste as the carbon source, which consisted of diatomaceous earth impregnated with esters from filters used in biodiesel purification. The highest bioemulsifier production occurred in mineral minimal medium containing 75 g/L biodiesel residue and 5 g/L ammonium sulfate. The highest emulsifying activity was obtained in medium containing 58 g/L biodiesel refinery residue and 4.6 g/L ammonium sulfate, and under these conditions, the model estimated an emulsifying activity of 85%. Gas chromatography and mass spectrometry analysis suggested a bioemulsifier molecule consisting of monosaccharides, predominantly xylose and mannose, and a long chain aliphatic groups composed of octadecanoic acid and hexadecanoic acid at concentrations of 48.01% and 43.16%, respectively. The carbohydrate composition as determined by GC-MS of their alditol acetate derivatives showed a larger ratio of xylose (49.27%, mannose (39.91%, and glucose (10.81%. 1 H NMR spectra confirmed by COSY suggested high molecular weight, polymeric pattern, presence of monosaccharide’s and long chain aliphatic groups in the bioemulsifier molecule. Conclusions The biodiesel residue is an economical substrate, therefore seems to be very promising for the low-cost production of active emulsifiers in the emulsification of aromatics, aliphatic hydrocarbons, and kerosene.

  18. Proceedings of the 10. world congress on anaerobic digestion 2004 : anaerobic bioconversion, answer for sustainability

    International Nuclear Information System (INIS)

    2004-01-01

    This conference reviewed the broad scope of anaerobic process-related activities taking place globally and confirmed the possibilities of using anaerobic processes to add value to industrial wastewaters, municipal solid wastes and organic wastes while minimizing pollution and greenhouse gases. It focused on biomolecular tools, instrumentation of anaerobic digestion processes, anaerobic bioremediation of chlorinated organics, and thermophilic and mesophilic digestion. Several papers focused on the feasibility of using waste products to produce hydrogen and methane for electricity generation. The sessions of the conference were entitled acidogenesis; microbial ecology; process control; sulfur content; technical development; domestic wastewater; agricultural waste; organic municipal solid wastes; instrumentation; molecular biology; sludges; agricultural feedstock; bioremediation; industrial wastewater; hydrogen production; pretreatments; sustainability; and integrated systems. The conference featured 387 posters and 192 oral presentations, of which 111 have been indexed separately for inclusion in this database. refs., tabs., figs

  19. Evaluation of ginsenoside bioconversion of lactic acid bacteria isolated from kimchi

    Directory of Open Access Journals (Sweden)

    Boyeon Park

    2017-10-01

    Conclusion: Ginsenoside Rg5 concentration of five LABs have ranged from ∼2.6 μg/mL to 6.5 μg/mL and increased in accordance with the incubation periods. Our results indicate that the enzymatic activity along with acidic condition contribute to the production of minor ginsenoside from lactic acid bacteria.

  20. Hydrocarbon bio-jet fuel from bioconversion of poplar biomass: techno-economic assessment.

    Science.gov (United States)

    Crawford, Jordan T; Shan, Chin Wei; Budsberg, Erik; Morgan, Hannah; Bura, Renata; Gustafson, Rick

    2016-01-01

    Infrastructure compatible hydrocarbon biofuel proposed to qualify as renewable transportation fuel under the U.S. Energy Independence and Security Act of 2007 and Renewable Fuel Standard (RFS2) is evaluated. The process uses a hybrid poplar feedstock, which undergoes dilute acid pretreatment and enzymatic hydrolysis. Sugars are fermented to acetic acid, which undergoes conversion to ethyl acetate, ethanol, ethylene, and finally a saturated hydrocarbon end product. An unfermentable lignin stream may be burned for steam and electricity production, or gasified to produce hydrogen. During biofuel production, hydrogen gas is required and may be obtained by various methods including lignin gasification. Both technical and economic aspects of the biorefinery are analyzed, with different hydrogen sources considered including steam reforming of natural gas and gasification of lignin. Cash operating costs for jet fuel production are estimated to range from 0.67 to 0.86 USD L -1 depending on facility capacity. Minimum fuel selling prices with a 15 % discount rate are estimated to range from 1.14 to 1.79 USD L -1 . Capacities of 76, 190, and 380 million liters of jet fuel per year are investigated. Capital investments range from 356 to 1026 million USD. A unique biorefinery is explored to produce a hydrocarbon biofuel with a high yield from bone dry wood of 330 L t -1 . This yield is achieved chiefly due to the use of acetogenic bacteria that do not produce carbon dioxide as a co-product during fermentation. Capital investment is significant in the biorefinery in part because hydrogen is required to produce a fully de-oxygenated fuel. Minimum selling price to achieve reasonable returns on investment is sensitive to capital financing options because of high capital costs. Various strategies, such as producing alternative, intermediate products, are investigated with the intent to reduce risk in building the proposed facility. It appears that producing and selling these intermediates may be more profitable than converting all the biomass into aviation fuel. With variability in historical petroleum prices and environmental subsidies, a high internal rate of return would be required to attract investors.

  1. Bioconversion of plant biomass to ethanol. Annual report and revised research plan, January 1977--January 1978

    Energy Technology Data Exchange (ETDEWEB)

    Brooks, R.E.; Bellamy, W.D.; Su, T.M.

    1978-03-23

    The objective of this research is to demonstrate on a laboratory scale the technical feasibility of the direct microbial conversion of pretreated wood to ethanol. During the first year of this contract, we investigated the feasibility of biologically delignifying wood with C. pruinosum and directly fermenting the pretreated wood to ethanol with a mixed culture. Bench-top fermentations of a thermophilic bacillus growing on glucose and of a mixed culture of thermophilic sporocytophaga (US) and a thermophilic bacillus growing on microcrystalline and amorphous cellulose were evaluated for growth and ethanol production. In the mixed culture fermentation of amorphous and microcrystalline cellulose, the specific rate of substrate depletion was calculated to be 0.087 hr/sup -1/ and 0.0346 hr/sup -1/, respectively. However, defining the growth requirements of C. pruinosum and sporocytophaga (US) proved more difficult than originally anticipated. In order to achieve the program objectives within the contract period, a revised research plan was developed based upon chemical pretreatment and the direct fermentation of pretreated hardwood to ethanol. In place of the biological delignification pretreatment step, we have substituted a chemically supplemented steam pretreatment step to partially delignify wood and to enhance its accessibility to microbial utilization. Clostridium thermocellum, which ferments cellulose directly to ethanol and acetic acid, has replaced the mixed culture fermentation stage for ethanol production. Research on the production of ethanol from xylose by the thermophilic bacillus ZB-B2 is retained as one means of utilizing the hemicellulose fraction of hardwood. Work on the genetic improvement of the ethanol yields of both cultures by suppressing acetic acid production is also retained. The rationale, experimental approach, and economic considerations of this revised research plan are also presented.

  2. Bioconversion of Biomass-Derived Phenols Catalyzed by Myceliophthora thermophila Laccase

    Directory of Open Access Journals (Sweden)

    Anastasia Zerva

    2016-04-01

    Full Text Available Biomass-derived phenols have recently arisen as an attractive alternative for building blocks to be used in synthetic applications, due to their widespread availability as an abundant renewable resource. In the present paper, commercial laccase from the thermophilic fungus Myceliophthora thermophila was used to bioconvert phenol monomers, namely catechol, pyrogallol and gallic acid in water. The resulting products from catechol and gallic acid were polymers that were partially characterized in respect to their optical and thermal properties, and their average molecular weight was estimated via solution viscosity measurements and GPC. FT-IR and 1H-NMR data suggest that phenol monomers are connected with ether or C–C bonds depending on the starting monomer, while the achieved molecular weight of polycatechol is found higher than the corresponding poly(gallic acid. On the other hand, under the same condition, pyrogallol was dimerized in a pure red crystalline compound and its structure was confirmed by 1H-NMR as purpurogallin. The herein studied green synthesis of enzymatically synthesized phenol polymers or biological active compounds could be exploited as an alternative synthetic route targeting a variety of applications.

  3. Reduction of Non-CO2 Gas Emissions Through The In Situ Bioconversion of Methane

    Energy Technology Data Exchange (ETDEWEB)

    Scott, A R; Mukhopadhyay, B; Balin, D F

    2012-09-06

    The primary objectives of this research were to seek previously unidentified anaerobic methanotrophs and other microorganisms to be collected from methane seeps associated with coal outcrops. Subsurface application of these microbes into anaerobic environments has the potential to reduce methane seepage along coal outcrop belts and in coal mines, thereby preventing hazardous explosions. Depending upon the types and characteristics of the methanotrophs identified, it may be possible to apply the microbes to other sources of methane emissions, which include landfills, rice cultivation, and industrial sources where methane can accumulate under buildings. Finally, the microbes collected and identified during this research also had the potential for useful applications in the chemical industry, as well as in a variety of microbial processes. Sample collection focused on the South Fork of Texas Creek located approximately 15 miles east of Durango, Colorado. The creek is located near the subsurface contact between the coal-bearing Fruitland Formation and the underlying Pictured Cliffs Sandstone. The methane seeps occur within the creek and in areas adjacent to the creek where faulting may allow fluids and gases to migrate to the surface. These seeps appear to have been there prior to coalbed methane development as extensive microbial soils have developed. Our investigations screened more than 500 enrichments but were unable to convince us that anaerobic methane oxidation (AMO) was occurring and that anaerobic methanotrophs may not have been present in the samples collected. In all cases, visual and microscopic observations noted that the early stage enrichments contained viable microbial cells. However, as the levels of the readily substrates that were present in the environmental samples were progressively lowered through serial transfers, the numbers of cells in the enrichments sharply dropped and were eliminated. While the results were disappointing we acknowledge that anaerobic methane oxidizing (AOM) microorganisms are predominantly found in marine habitats and grow poorly under most laboratory conditions. One path for future research would be to use a small rotary rig to collect samples from deeper soil horizons, possibly adjacent to the coal-bearing horizons that may be more anaerobic.

  4. COMBINED COMPOST AND VERMICOMPOSTING PROCESS IN THE TREATMENT AND BIOCONVERSION OF SLUDGE

    Directory of Open Access Journals (Sweden)

    H. Alidadi, A. R. Parvaresh and M. R. Shamansouri

    2005-10-01

    Full Text Available Traditional thermophillic composting is commonly for treatment of sludge. A related technique as vermicomposting process, using earthworms to breakdown sludge, is also becoming popular. These two techniques have their inherent advantages and disadvantages. The combined approach suggested in this study to enhance the overall process and improve the products qualities. Two systems,vermicomposting and combined compost vermicomposting processes, have been investigated in this study. The sludge used in this study was obtained from the drying beds of South Isfahan wastewater treatment plant.The sludge mixed with sawdust to provide C/N ratio of 25/1.Eisenia fetida was the species of earthworms used in the vermicomposting processes.The results obtained indicates reduction in the amount of volatile solids,total carbon and C/N ratio with the vermicompost age,which indicates the reduction in the biodegradable organic content and mineralization of sludge. Also increase in phosphorus concentration by the end process because of mineralization of organic matter. The results indicate that, a system that combines the two mentioned processes not only shortens stabilization time, but also improves the products quality. Combining the two systems resulted in a product that was more stable and homogenous; the product could meet the pathogen reduction requirements.

  5. Multidisciplinary research program directed toward utilization of solar energy through bioconversion of renewable resources

    Energy Technology Data Exchange (ETDEWEB)

    1980-07-01

    Progress is reported in this multidisciplinary research program. Genetic selection of superior trees, physiological basis of vigor, tissue culture systems leading to cloning of diploid and haploid cell lines are discussed in the Program A report. The physiological basis of enhanced oleoresin formation in southern pines when treated with sublethal concentrations of the herbicide paraquat was investigated in Program B. In Program C, metabolic changes in the stems of slash pine, in vivo, after application with paraquat were determined. The use of phdoem and xylem tissue slices as a laboratory model for studying paraquat associated- and normal-terpene synthesis in pines is discussed. The biochemistry and physiology of methane formation from cellulose during anaerobic fermentation are discussed in the Program D report. (DMC)

  6. Bioconversions of Palm Kernel Cake and Rice Bran Mixtures by Trichoderma viride Toward Nutritional Contents

    Directory of Open Access Journals (Sweden)

    Yana Sukaryana

    2010-12-01

    Full Text Available The objective of the research is to examine the mixtures of palm kernel cake and rice bran of fermented by Trichoderma viride. Completely randomized design in factorial pattern 4 x 4 was used in this experiment. factor I is the doses of inoculums; D1 = 0%, D2 =  0,1% , D3 =  0,2%, D4 =  0,3%, and  complement factor II is mixtures of palm kernel cake and rice bran : T1=20:80% ; T2=40:60% ; T3=60:40% ; T4=80:20%. The treatment each of three replicate. Fermentation was conducted at temperature 28 oC as long as 9 days. Determining the best of the mixtures be based on the crude protein increased and the crude fibre decreased. The results showed that the combination of product mix is the best fermentation inoculums doses 0.3% in mixture of palm kernel cake and rice bran ; 80%: 20%, which produces dry matter of 88,12%, crude protein 17.34%, ether extract 5,35%, crude fibre 23.67%, and ash 6.43%. When compared with a mixture of palm kernel cake and rice bran; 80%: 20% without of fermentation is crude protein increase 29.58% and crude fibre decreased 22.53%.

  7. Bioconversions of Palm Kernel Cake and Rice Bran Mixtures by Trichoderma viride Toward Nutritional Contents

    OpenAIRE

    Yana Sukaryana; Umi Atmomarsono; Vitus D. Yunianto; Ejeng Supriyatna

    2010-01-01

    The objective of the research is to examine the mixtures of palm kernel cake and rice bran of fermented by Trichoderma viride. Completely randomized design in factorial pattern 4 x 4 was used in this experiment. factor I is the doses of inoculums; D1 = 0%, D2 =  0,1% , D3 =  0,2%, D4 =  0,3%, and  complement factor II is mixtures of palm kernel cake and rice bran : T1=20:80% ; T2=40:60% ; T3=60:40% ; T4=80:20%. The treatment each of three replicate. Fermentation was conduc...

  8. Bioconversion of lignocellulose-derived sugars to ethanol by engineered Saccharomyces cerevisiae.

    Science.gov (United States)

    Madhavan, Anjali; Srivastava, Aradhana; Kondo, Akihiko; Bisaria, Virendra S

    2012-03-01

    Lignocellulosic biomass from agricultural and agro-industrial residues represents one of the most important renewable resources that can be utilized for the biological production of ethanol. The yeast Saccharomyces cerevisiae is widely used for the commercial production of bioethanol from sucrose or starch-derived glucose. While glucose and other hexose sugars like galactose and mannose can be fermented to ethanol by S. cerevisiae, the major pentose sugars D-xylose and L-arabinose remain unutilized. Nevertheless, D-xylulose, the keto isomer of xylose, can be fermented slowly by the yeast and thus, the incorporation of functional routes for the conversion of xylose and arabinose to xylulose or xylulose-5-phosphate in Saccharomyces cerevisiae can help to improve the ethanol productivity and make the fermentation process more cost-effective. Other crucial bottlenecks in pentose fermentation include low activity of the pentose phosphate pathway enzymes and competitive inhibition of xylose and arabinose transport into the cell cytoplasm by glucose and other hexose sugars. Along with a brief introduction of the pretreatment of lignocellulose and detoxification of the hydrolysate, this review provides an updated overview of (a) the key steps involved in the uptake and metabolism of the hexose sugars: glucose, galactose, and mannose, together with the pentose sugars: xylose and arabinose, (b) various factors that play a major role in the efficient fermentation of pentose sugars along with hexose sugars, and (c) the approaches used to overcome the metabolic constraints in the production of bioethanol from lignocellulose-derived sugars by developing recombinant S. cerevisiae strains.

  9. Pilot-scale demonstration of SPORL for bioconversion of lodgepole pine to bioethanol and lignosulfonate

    Science.gov (United States)

    Haifeng Zhou; Junyong Zhu; Roland Gleisner; Xueqing Qiu; Eric Horn; Jose Negron

    2016-01-01

    The process sulfite pretreatment to overcome recalcitrance of lignocelluloses (SPORL) has been the focus of this study. Pilot-scale (50 kg) pretreatment of wood chips of lodgepole pine (Pinus contorta Douglas ex Loudon) killed by mountain pine beetle (Dendroctonus ponderosae Hopkins) were conducted at 165°C...

  10. Bioconversion of cellulose to liquid fuel (ethanol). Final report, Stage 2, 1983-06-30

    Energy Technology Data Exchange (ETDEWEB)

    Hahn-Haegerdal, B

    1983-01-01

    The process routes of the conversion have been investigated. The material which contains lignocellulose should be pretreated, and the separate processes are to be integrated. The price of raw materials and enzymes influences the process economy. The efficiency of biocatalysts on fermentation and saccharification are being studied and the reuse of enzymes is discussed. The process for the production of ethanol out of lignocellulose is shown to be very complicated. The optimization of the process will necessitate computerized simulation.

  11. Use of Swine Wastewater as Alternative Substrate for Mycelial Bioconversion of White Rot Fungi.

    Science.gov (United States)

    Lee, Jangwoo; Shin, Seung Gu; Ahn, Jinmo; Han, Gyuseong; Hwang, Kwanghyun; Kim, Woong; Hwang, Seokhwan

    2017-02-01

    Seven white rot fungal species were tested for growth as mycelia using swine wastewater (SW), an agro-waste with tremendous environmental footprint, as the sole nutrient source. The SW contained high concentrations of carbon and nitrogen components, which could support nutritional requirements for mycelial growth. Out of the seven species, Pleurotus ostreatus and Hericium erinaceus were successfully cultivated on the SW medium using solid-state fermentation. Response surface methodology was employed to determine the combination of pH, temperature (T), and substrate concentration (C) that maximizes mycelial growth rate (Kr) for the two species. The optimum condition was estimated as pH = 5.8, T = 28.8 °C, and C = 11.2 g chemical oxygen demand (COD)/L for P. ostreatus to yield Kr of 11.0 mm/day, whereas the greatest Kr (3.1 mm/day) was anticipated at pH = 4.6, T = 25.5 °C, and C = 11.9 g COD/L for H. erinaceus. These Kr values were comparable to growth rates obtained using other substrates in the literature. These results demonstrate that SW can be used as an effective substrate for mycelial cultivation of the two white rot fungal species, suggesting an alternative method to manage SW with the production of potentially valuable biomass.

  12. Optimization of H2SO4-catalyzed hydrothermal pretreatment of rapeseed straw for bioconversion to ethanol

    DEFF Research Database (Denmark)

    Xuebin, Lu; Zhang, Y.; Angelidaki, Irini

    2009-01-01

    A central composite design of response surface method was used to optimize H2SO4-catalyzed hydrothermal pretreatment of rapeseed straw, in respect to acid concentration (0.5-2%), treatment time (5-20 min) and solid content (10-20%) at 180 degrees C. Enzymatic hydrolysis and fermentation were also...... content for 10 min at 180 degrees C was found to be the most optimal condition for pretreatment of rapeseed straw for ethanol production. After pretreatment at the optimal condition and enzymatic hydrolysis, 75.12% total xylan and 63.17% total glucan were converted to xylose and glucose, respectively...

  13. Bioconversion of empty fruit bunches (EFB) and palm oil mill effluent ...

    African Journals Online (AJOL)

    This study shows the performance of Trichoderma virens as an activator for conversion of empty fruit bunches (EFB) and palm oil mill effluent (POME) into compost. EFB and POME are two abundant wastes produced by oil palm industries which keep accumulating. Since there is no proper way to dispose these wastes, ...

  14. New cultive medium for bioconversion of C5 fraction from sugarcane bagasse using rice bran extract

    Directory of Open Access Journals (Sweden)

    Debora Danielle Virginio da Silva

    2014-12-01

    Full Text Available The use of hemicellulosic hydrolysates in bioprocesses requires supplementation as to ensure the best fermentative performance of microorganisms. However, in light of conflicting data in the literature, it is necessary to establish an inexpensive and applicable medium for the development of bioprocesses. This paper evaluates the fermentative performance of Scheffersomyces (Pichia stipitis and Candida guilliermondii growth in sugarcane bagasse hemicellulosic hydrolysate supplemented with different nitrogen sources including rice bran extract, an important by-product of agroindustry and source of vitamins and amino acids. Experiments were carried out with hydrolysate supplemented with rice bran extract and (NH42SO4; peptone and yeast extract; (NH42SO4, peptone and yeast extract and non-supplemented hydrolysate as a control. S. stipitis produced only ethanol, while C. guilliermondii produced xylitol as the main product and ethanol as by-product. Maximum ethanol production by S. stipitis was observed when sugarcane bagasse hemicellulosic hydrolysate was supplemented with (NH42SO4, peptone and yeast extract. Differently, the maximum xylitol formation by C. guilliermondii was obtained by employing hydrolysate supplemented with (NH42SO4 and rice bran extract. Together, these findings indicate that: a for both yeasts (NH42SO4 was required as an inorganic nitrogen source to supplement sugarcane bagasse hydrolysate; b for S. stipitis, sugarcane hemicellulosic hydrolysate must be supplemented with peptone and yeast extract as organic nitrogen source; and: c for C. guilliermondii, it must be supplemented with rice bran extract. The present study designed a fermentation medium employing hemicellulosic hydrolysate and provides a basis for studies about value-added products as ethanol and xylitol from lignocellulosic materials.

  15. Bioconversion of sugar cane molasses into glutamic acid by gamma irradiated corynebacterium glutamicum

    International Nuclear Information System (INIS)

    El-Batal, A.I.

    1996-01-01

    Corynebacterium glutamicum (ATCC 13058) was used for glutamic acid production from sugar cane molasses which contain sufficient. The addition of 5 units ml 4 of penicillin G was superior in glutamic acid production (11.5 g L 4 ). Tweens and their saturated fatty acids were effective on the accumulation of glutamic acid in the culture medium and the maximum yield (16.6 g L 4 ) was the addition of 5 mg ml 4 Tween 40. Gamma irradiation prior to Tween-40 treatment of bacterial cells resulted in an obvious increase in glutamic acid production and it was maximum (23.72 g L 4 ) at 0.1 k Gy exposure dose of inocula. 5 tabs

  16. Bioconversion of dieldrin by wood-rotting fungi and metabolite detection.

    Science.gov (United States)

    Kamei, Ichiro; Takagi, Kazuhiro; Kondo, Ryuichiro

    2010-08-01

    Dieldrin is one of the most persistent organochlorine pesticides, listed as one of the 12 persistent organic pollutants in the Stockholm Convention. Although microbial degradation is an effective way to remediate environmental pollutants, reports on aerobic microbial degradation of dieldrin are limited. Wood-rotting fungi can degrade a wide spectrum of recalcitrant organopollutants, and an attempt has been made to select wood-rotting fungi that can degrade dieldrin, and to identify the metabolite. Thirty-four isolates of wood-rotting fungi were investigated for their ability to degrade dieldrin. Strain YK543 degraded 39.1 +/- 8.8% of dieldrin during 30 days of incubation. Phylogenetic analysis demonstrated that strain YK543 was closely related to the fungus Phlebia brevispora Nakasone TMIC33929, which has been reported as a fungus that can degrade chlorinated dioxins and polychlorinated biphenyls. 9-Hydroxydieldrin was detected as a metabolite in the cultures of strain YK543. It is important to select the microorganisms that degrade organic pollutants, and to identify the metabolic pathway for the development of bioremediation methods. Strain YK543 was selected as a fungus capable of degrading dieldrin. The metabolic pathway includes 9-hydroxylation reported in rat's metabolism catalysed by liver microsomal monooxygenase. This is the first report of transformation of dieldrin to 9-hydroxydieldrin by a microorganism. Copyright (c) 2010 Society of Chemical Industry.

  17. Optimization studies for the bioconversion of Jerusalem artichoke tubers to ethanol and microbial biomass

    Energy Technology Data Exchange (ETDEWEB)

    Margaritis, A.; Bajpai, P.; Cannell, E.

    1981-01-01

    A total of 8 yeast and other microbial cultures were grown in the extract derived from the tubers of Jerusalem artichoke (Helianthus tuberosus) and screened according to the following optimization criteria: rates and yields of ethanol production, rates and yields of biomass production, and percent of original sugars utilized during fermentation. Batch growth kinetic parameters were also determined for the cultures studied. Kluyveromyces marxianus UCD (FST) 55-82 had the highest specific growth rate, 0.41/h, with a high ethanol yield, 88% of theoretical.

  18. Bioconversion of potatoes residues or surplus potatoes to ethanol under non axenic conditions [abstract

    Directory of Open Access Journals (Sweden)

    Lamaudière, S.

    2010-01-01

    Full Text Available Biofuels can offer an alternative to fossil fuels in the context of climate change and fossil reserves depletion. With 3 million tons of potatoes produced in 2007 and a high yield per hectare of 47 tons, Belgium is the 19th largest producer in the world. The residual and surplus potatoes could be used to produce bioethanol by fermentation. We examined the feasibility of a simple ethanol fermentation process under non axenic conditions. The substrate was pretreated with commercial amylases or by adding as low as 10% FM (Fresh Matter barley malt. It was then fermented with Saccharomyces cerevisiae. Ethanol and volatile fatty acids were analyzed by GC-FID and soluble sugars were analyzed with the Anthrone method. Starch from potatoes was hydrolyzed to soluble sugars. Hydrolysis seems to continue with 10% FM of barley malt after 48 h while the hydrolysis stopped or decelerated with commercial enzymes. With 10% FM of malt, 3 h of hydrolysis and 7 days of fermentation, an ethanol concentration of 42 g.l-1 was obtained and the conversion yield was 139 gethanol.kg-1 DM. The fermentation conversion yield of soluble sugars to ethanol was > 82% and the endogenous competition was limited. However, starch hydrolyzing seems to be a limiting step under the conditions tested. Commercial enzymes did not provide better results under the same conditions.

  19. Malolactic bioconversion using a Oenococcus oeni strain for cider production: effect of yeast extract supplementation.

    Science.gov (United States)

    Herrero, Mónica; García, Luis A; Díaz, Mario

    2003-12-01

    Yeast extract addition to reconstituted apple juice had a positive impact on the development of the malolactic starter culture used to ensure malolactic fermentation in cider, using active but non-proliferating cells. In this work, the reuse of fermentation lees from cider is proposed as an alternative to the use of commercial yeast extract products. Malolactic enzymatic assays, both in whole cells and cell-free extracts, were carried out to determine the best time to harvest cells for use as an inoculum in cider. Cells harvested at the late exponential phase, the physiological stage of growth corresponding to the maximum values of specific malolactic activity, achieved a good rate of malic acid degradation in controlled cider fermentation. Under the laboratory conditions used, malic acid degradation rates in the fermentation media turned out to be near 2.0 and 2.5 times lower, compared with the rates obtained in whole-cell enzymatic assays, as useful data applicable to industrial cider production.

  20. An integrated bioconversion process for the production of L-lactic acid from starchy feedstocks

    Energy Technology Data Exchange (ETDEWEB)

    Tsai, S.P.; Moon, S.H.

    1997-07-01

    The potential market for lactic acid as the feedstock for biodegradable polymers, oxygenated chemicals, and specialty chemicals is significant. L-lactic acid is often the desired enantiomer for such applications. However, stereospecific lactobacilli do not metabolize starch efficiently. In this work, Argonne researchers have developed a process to convert starchy feedstocks into L-lactic acid. The processing steps include starch recovery, continuous liquefaction, and simultaneous saccharification and fermentation. Over 100 g/L of lactic acid was produced in less than 48 h. The optical purity of the product was greater than 95%. This process has potential economical advantages over the conventional process.

  1. Heliosynthesis: A solar biotechnology based on direct bioconversion of solar energy by photosynthetic cells

    Science.gov (United States)

    Gudin, C.

    1982-12-01

    Certain limiting aspects of current technology should be studied, such as the lifetimes of tubing material and the utilization of renewable sources of energy for pumping. Only exocellular or cellular biomass with high specific value, involving small markets and small plant areas (less than 1 ha), will be economically possible for the short term and will allow improvement of this technology. A valorization of the totality of photosynthetic biomass with respect to economics and energy is an absolute necessity. There is an immediate need for genetic studies of microalgae that will allow enhancement or even creation of chemical production satisfying economic and energy needs. Such efforts should permit the rapid establishment of an aggressive and sophisticated solar biotechnology that integrates scientific and technical' developments to meet the new needs of humanity for food, chemicals, and energy, thereby complementing agriculture with a sort of cellular horticulture.

  2. Bioconversion of hydrolyzed cashew peduncle bagasse for ethanol and xylitol production

    Directory of Open Access Journals (Sweden)

    Lorena L. de Medeiros

    Full Text Available ABSTRACT The agro-industrial waste deposited in the environment causes problems in nature that can be solved with the use and generation of bioproducts. Thus, the objective was to study the lignocellulosic fraction of cashew (Anacardium occidentale L. peduncle bagasse and fermentation on large scale (8-16 times using the strain Candida guilliermondii CCT-3544 as production agent. According to the obtained results, it can be noted that the dry cashew peduncle bagasse has 21.45% of cellulose, 10.96% of hemicellulose and 35.39% of lignin. During fermentation, C. guilliermondii 3544-CAT was able to grow on medium containing hydrolysate, with maximum cell growth concentration of 3.5 g L-1. The behavior of the sugars in the fermentation process was similar in the different variables, with maximum production of ethanol and xylitol at 48 h of fermentation.

  3. Integrated cellulosic enzymes hydrolysis and fermentative advanced yeast bioconversion solution ready for biomass biorefineries

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Manoj [DSM Innovation, Inc., San Francisco, CA (United States)

    2011-05-04

    These are slides from this conference. Lignocellulosic biomass is the most abundant, least expensive renewable natural biological resource for the production of biobased products and bioenergy is important for the sustainable development of human civilization in 21st century. For making the fermentable sugars from lignocellulosic biomass, a reduction in cellulase production cost, an improvement in cellulase performance, and an increase in sugar yields are all vital to reduce the processing costs of biorefineries. Improvements in specific cellulase activities for non-complexed cellulase mixtures can be implemented through cellulase engineering based on rational design or directed evolution for each cellulase component enzyme, as well as on the reconstitution of cellulase components. In this paper, we will provide DSM's efforts in cellulase research and developments and focus on limitations. Cellulase improvement strategies based on directed evolution using screening on relevant substrates, screening for higher thermal tolerance based on activity screening approaches such as continuous culture using insoluble cellulosic substrates as a powerful selection tool for enriching beneficial cellulase mutants from the large library. We will illustrate why and how thermostable cellulases are vital for economic delivery of bioproducts from cellulosic biomass using biochemical conversion approach.

  4. Microbial and Bioconversion Production of D-xylitol and Its Detection and Application

    Science.gov (United States)

    Chen, Xi; Jiang, Zi-Hua; Chen, Sanfeng; Qin, Wensheng

    2010-01-01

    D-Xylitol is found in low content as a natural constituent of many fruits and vegetables. It is a five-carbon sugar polyol and has been used as a food additive and sweetening agent to replace sucrose, especially for non-insulin dependent diabetics. It has multiple beneficial health effects, such as the prevention of dental caries, and acute otitis media. In industry, it has been produced by chemical reduction of D-xylose mainly from photosynthetic biomass hydrolysates. As an alternative method of chemical reduction, biosynthesis of D-xylitol has been focused on the metabolically engineered Saccharomyces cerevisiae and Candida strains. In order to detect D-xylitol in the production processes, several detection methods have been established, such as gas chromatography (GC)-based methods, high performance liquid chromatography (HPLC)-based methods, LC-MS methods, and capillary electrophoresis methods (CE). The advantages and disadvantages of these methods are compared in this review. PMID:21179590

  5. Bioconversion of oil sludge into biomass of lipid metabolites for use as a source of biofuel

    Science.gov (United States)

    Shchemelinina, T. N.; Matistov, N. V.; Markarova, M. Yu; Anchugova, E. M.

    2018-01-01

    The possibilities for the generation of biofuel from the results of the accumulation of lipids in oil-contaminated environments were studied. This type of accumulation occurs in the biomass of yeast strains Rhodotorula sp. VKM Y-2993D; in bacteria like Pseudomonas libanensis B-3041D and in consortia of microalgal strains such as Acutodesmus obliquus Syko-A Ch-055-12, Chlorella sp. SYKO A Ch-011-10, Monoraphidium sp., and Anabaena sp. The most promising of these for processing petroleum hydrocarbons into biofuels was found to be the consortium of microalgal strains, the content of palmitic acid of which reached 49.0 %, thereby achieving a mid-range cetane number.

  6. Bioconversion of Sugarcane Vinasse into High-Added Value Products and Energy

    Science.gov (United States)

    Machado, Antonio Carlos de Oliveira

    2017-01-01

    Vinasse, a residue from bioethanol production containing high organic matter concentration, was used as substrate in submerged fermentation of Pseudomonas aeruginosa PA1 for biosurfactant production. About 2.7 g/L of rhamnolipids was obtained, with surface tension of 29.2 mN/m and critical micelle concentration of 80.3 mg/L. After separation of rhamnolipid and biomass, residual fermentation media were submitted to anaerobic biodegradation in mesophilic conditions. The residual medium derived from fermentation with vinasse diluted to 1 : 1, without addition of nitrogen, C : N 21, and for 168 h, led to 63.2% chemical oxygen demand (COD) removal and 97.6 mL CH4/g CODremoved. Compared to results obtained with fresh vinasse (73.7% COD removal and 112.4 mL CH4/g CODremoved), it could be concluded that both processes can be integrated in order to add value to the residue and obtain energy, reducing production costs and at the same time environmental impacts related to vinasse disposal. PMID:29250551

  7. Bioconversion potential of Trichoderma viride HN1 cellulase for a lignocellulosic biomass Saccharum spontaneum.

    Science.gov (United States)

    Iqtedar, Mehwish; Nadeem, Mohammad; Naeem, Hira; Abdullah, Roheena; Naz, Shagufta; Qurat ul Ain Syed; Kaleem, Afshan

    2015-01-01

    The industrialisation of lignocellulose conversion is impeded by expensive cellulase enzymes required for saccharification in bioethanol production. Current research undertakes cellulase production from pretreated Saccharum spontaneum through Trichoderma viride HN1 under submerged fermentation conditions. Pretreatment of substrate with 2% NaOH resulted in 88% delignification. Maximum cellulase production (2603 ± 16.39 U/mL/min carboxymethyl cellulase and 1393 ± 25.55 U/mL/min FPase) was achieved at 6% substrate at pH 5.0, with 5% inoculum, incubated at 35°C for 120 h of fermentation period. Addition of surfactant, Tween 80 and metal ion Mn(+2), significantly enhanced cellulase yield. This study accounts proficient cellulase yield through process optimisation by exploiting cheaper substrate to escalate their commercial endeavour.

  8. Lignocellulose-Adapted Endo-Cellulase Producing Streptomyces Strains for Bioconversion of Cellulose-Based Materials.

    Science.gov (United States)

    Ventorino, Valeria; Ionata, Elena; Birolo, Leila; Montella, Salvatore; Marcolongo, Loredana; de Chiaro, Addolorata; Espresso, Francesco; Faraco, Vincenza; Pepe, Olimpia

    2016-01-01

    Twenty-four Actinobacteria strains, isolated from Arundo donax, Eucalyptus camaldulensis and Populus nigra biomass during natural biodegradation and with potential enzymatic activities specific for the degradation of lignocellulosic materials, were identified by a polyphasic approach. All strains belonged to the genus Streptomyces ( S .) and in particular, the most highly represented species was Streptomyces argenteolus representing 50% of strains, while 8 strains were identified as Streptomyces flavogriseus (synonym S. flavovirens ) and Streptomyces fimicarius (synonyms Streptomyces acrimycini, Streptomyces baarnensis, Streptomyces caviscabies , and Streptomyces flavofuscus ), and the other four strains belonged to the species Streptomyces drozdowiczii, Streptomyces rubrogriseus, Streptomyces albolongus , and Streptomyces ambofaciens . Moreover, all Streptomyces strains, tested for endo and exo-cellulase, cellobiase, xylanase, pectinase, ligninase, peroxidase, and laccase activities using qualitative and semi-quantitative methods on solid growth medium, exhibited multiple enzymatic activities (from three to six). The 24 strains were further screened for endo-cellulase activity in liquid growth medium and the four best endo-cellulase producers ( S. argenteolus AE58P, S. argenteolus AE710A, S. argenteolus AE82P, and S. argenteolus AP51A) were subjected to partial characterization and their enzymatic crude extracts adopted to perform saccharification experiments on A. donax pretreated biomass. The degree of cellulose and xylan hydrolysis was evaluated by determining the kinetics of glucose and xylose release during 72 h incubation at 50°C from the pretreated biomass in the presence of cellulose degrading enzymes (cellulase and β-glucosidase) and xylan related activities (xylanase and β-xylosidase). The experiments were carried out utilizing the endo-cellulase activities from the selected S. argenteolus strains supplemented with commercial β-gucosidase and xylanase preparations from Genencore (Accellerase BG and Accellerase XY). Cellulose and xylan conversion, when conducted using commercial (hemi)cellulases, gave glucose and xylose yields of 30.17 and 68.9%, respectively. The replacement of the cellulolytic preparation from Genencor (Accellerase 1500), with the endo-cellulase from S. argenteolus AE58P resulted in almost 76% of the glucose yield obtained in the presence of the commercial counterpart. Due to the promising results obtained by using the enzymatic crude extracts from S. argenteolus AE58P in the pretreated A. donax saccharification experiments, the proteins putatively responsible for endo-cellulase activity in this strain were identified by proteomics. Several proteins were confidently identified in different Streptomyces spp., eight of which belong to the class of Carbohydrate active enzymes. Overall results highlighted the biotechnological potential of S. argenteolus AE58P being an interesting candidate biocatalyst-producing bacterium for lignocellulose conversion and production of biochemicals and bioenergy.

  9. Bioconversion of corn stover hydrolysate to ethanol by a recombinant yeast strain

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Jing; Xia, Liming

    2010-12-15

    Three corn stover hydrolysates, enzymatic hydrolysates prepared from acid and alkaline pretreatments separately and hemicellulosic hydrolysate prepared from acid pretreatment, were evaluated in composition and fermentability. For enzymatic hydrolysate from alkaline pretreatment, ethanol yield on fermentable sugars and fermentation efficiency reached highest among the three hydrolysates; meanwhile, ethanol yield on dry corn stover reached 0.175 g/g, higher than the sum of those of two hydrolysates from acid pretreatment. Fermentation process of the enzymatic hydrolysate from alkaline pretreatment was further investigated using free and immobilized cells of recombinant Saccharomyces cerevisiae ZU-10. Concentrated hydrolysate containing 66.9 g/L glucose and 32.1 g/L xylose was utilized. In the fermentation with free cells, 41.2 g/L ethanol was obtained within 72 h with an ethanol yield on fermentable sugars of 0.416 g/g. Immobilized cells greatly enhanced the ethanol productivity, while the ethanol yield on fermentable sugars of 0.411 g/g could still be reached. Repeated batch fermentation with immobilized cells was further attempted up to six batches. The ethanol yield on fermentable sugars maintained above 0.403 g/g with all glucose and more than 92.83% xylose utilized in each batch. These results demonstrate the feasibility and efficiency of ethanol production from corn stover hydrolysates. (author)

  10. Development of a continuous bioconversion system using a thermophilic whole-cell biocatalyst.

    Science.gov (United States)

    Ninh, Pham Huynh; Honda, Kohsuke; Yokohigashi, Yukako; Okano, Kenji; Omasa, Takeshi; Ohtake, Hisao

    2013-03-01

    The heat treatment of recombinant mesophilic cells having heterologous thermophilic enzymes results in the denaturation of indigenous mesophilic enzymes and the elimination of undesired side reactions; therefore, highly selective whole-cell catalysts comparable to purified enzymes can be readily prepared. However, the thermolysis of host cells leads to the heat-induced leakage of thermophilic enzymes, which are produced as soluble proteins, limiting the exploitation of their excellent stability in repeated and continuous reactions. In this study, Escherichia coli cells having the thermophilic fumarase from Thermus thermophilus (TtFTA) were treated with glutaraldehyde to prevent the heat-induced leakage of the enzyme, and the resulting cells were used as a whole-cell catalyst in repeated and continuous reactions. Interestingly, although electron microscopic observations revealed that the cellular structure of glutaraldehyde-treated E. coli was not apparently changed by the heat treatment, the membrane permeability of the heated cells to relatively small molecules (up to at least 3 kDa) was significantly improved. By applying the glutaraldehyde-treated E. coli having TtFTA to a continuous reactor equipped with a cell-separation membrane filter, the enzymatic hydration of fumarate to malate could be operated for more than 600 min with a molar conversion yield of 60% or higher.

  11. Bioconversion Studies of Methyl Laurate to Dodecanedioic Acid using a Wild-type of Candida tropicalis

    Directory of Open Access Journals (Sweden)

    Akmalina Rifkah

    2018-01-01

    Full Text Available Production of dodecanedioic acid (DDDA, a platform chemical used as raw material for various commodities and polymers, has been studied through a biological process. This process was conducted by using a wild-type of Candida tropicalis which can be obtained easily from natural resources. The aim of this research was to study the characteristics of DDDA production from methyl laurate through batch fermentation process. Growth phase was carried out for 20 h, as the beginning of fermentation, then continued to conversion phase for 5 until 6 days. Utilization of methyl laurate and production of DDDA were analysed using gas chromatography, which proved the ability of C. tropicalis in assimilating methyl laurate to convert it become DDDA. The highest value of cells yield (Yx/s and DDDA yield (Yp/s successfully obtained were 0.86 g cells/g methyl laurate and 0.20 g DDDA/g methyl laurate, respectively. This study also showed the possibility of fermentation products accumulation as intermediate, or accumulation of DDDA inside the cells. Thus, this study can be applied as an alternative in addition to the use of mutant microorganism in producing DDDA.

  12. Efficient bioconversion of rice straw to ethanol with TiO2/UV pretreatment.

    Science.gov (United States)

    Kang, Hee-Kyoung; Kim, Doman

    2012-01-01

    Rice straw is a lignocellulosic biomass that constitutes a renewable organic substance and alternative source of energy; however, its structure confounds the liberation of monosaccharides. Pretreating rice straw using a TiO(2)/UV system facilitated its hydrolysis with Accellerase 1000(™), suggesting that hydroxyl radicals (OH·) from the TiO(2)/UV system could degrade lignin and carbohydrates. TiO(2)/UV pretreatment was an essential step for conversion of hemicellulose to xylose; optimal conditions for this conversion were a TiO(2) concentration of 0.1% (w/v) and an irradiation time of 2 h with a UV-C lamp at 254 nm. After enzymatic hydrolysis, the sugar yields from rice straw pretreated with these parameters were 59.8 ± 0.7% of the theoretical for glucose (339 ± 13 mg/g rice straw) and 50.3 ± 2.8% for xylose (64 ± 3 mg/g rice straw). The fermentation of enzymatic hydrolysates containing 10.5 g glucose/L and 3.2 g xylose/L with Pichia stipitis produced 3.9 g ethanol/L with a corresponding yield of 0.39 g/g rice straw. The maximum possible ethanol conversion rate is 76.47%. TiO(2)/UV pretreatment can be performed at room temperature and atmospheric pressure and demonstrates potential in large-scale production of fermentable sugars.

  13. Bioconversion of apigenin-7-O-β-glucoside in aqueous two-phase system

    Directory of Open Access Journals (Sweden)

    Ilić Sanja M.

    2005-01-01

    Full Text Available The study is concerned with the conversion of apigenin-7-O-β-glucoside into apigenin in polyethylene glycol 6000 / dextran 20000 aqueous two-phase system by β-glucosidase. Apigenin was separated from apigenin-7-O-β-glucoside and β-glucosidase by their partition into opposite phases. In 14% PEG / 22.5% DEX aqueous two-phase system obtained yield of apigenin in top phase was 108%.

  14. Pilot plant studies of the bioconversion of cellulose and production of ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Wilke, C.R.

    1977-01-31

    Progress is reported in several areas of research. The following cellulosic raw materials were selected for study: wheat, barley, and rice straws, rice hulls, sorghum, corn stover, cotton gin trash, newsprint, ground wood, and masonite steam-treated Douglas fir and redwood. Samples were collected, prepared, and analyzed for hexosans, pentosans, lignin, ash, and protein. Results of acid extraction and enzymatic hydrolysis are discussed. Yields of glucose, polyglucose, xylose, and arabinose are reported. Progress in process design and economic studies, as well as pilot plant process development and design studies, is summarized. (JGB)

  15. Evaluation energy efficiency of bioconversion knot rejects to ethanol in comparison to other thermochemically pretreated biomass

    Science.gov (United States)

    Zhaojiang Wang; Menghua Qin; J.Y. Zhu; Guoyu Tian; Zongquan. Li

    2013-01-01

    Rejects from sulfite pulp mill that otherwise would be disposed of by incineration were converted to ethanol by a combined physical–biological process that was comprised of physical refining and simultaneous saccharification and fermentation (SSF). The energy efficiency was evaluated with comparison to thermochemically pretreated biomass, such as those pretreated by...

  16. Release of Polyphenols Is the Major Factor Influencing the Bioconversion of Rice Straw to Lactic Acid.

    Science.gov (United States)

    Chen, Xingxuan; Xue, Yiyun; Hu, Jiajun; Tsang, Yiu Fai; Gao, Min-Tian

    2017-11-01

    In this study, we found that p-coumaric acid (p-CA), ferulic acid (FA), and condensed tannins were released from rice straw during saccharification. The presence of polyphenols prolonged the lag phase and lowered the productivity of lactic acid. p-CA was identified as a key inhibitor. Tannins had a lower inhibitory effect than p-CA; FA had little inhibitory effect. Acid, alkaline, and ball milling pretreatments elicited different levels of polyphenol release from rice straw. Due to the different levels of polyphenol release in the pretreatment step, the enzymatic hydrolysates contained different concentrations of polyphenols. Compared with fermentation with a synthetic medium, fermentation with the hydrolysates of ball-milled rice straw provided much lower productivity and yield of lactic acid due to the presence of polyphenols. Removal of these compounds played an important role in lactic acid fermentation. When rice straw was alkaline pretreated, the hydrolysates contained few phenolic compounds, resulting in high productivity and yield of lactic acid (1.8 g/L/h and 26.7 g/100 g straw), which were comparable to those in a synthetic medium. This indicates that there is a correlation between removal of phenolic compounds and efficiency in lactic acid fermentation.

  17. A comprehensive model of anaerobic bioconversion of complex substrates to biogas

    DEFF Research Database (Denmark)

    Angelidaki, Irini; Ellegaard, Lars; Ahring, Birgitte Kiær

    1999-01-01

    A dynamic model describing the anaerobic degradation of complex material, and codigestion of different types of wastes, was developed based on a model previously described (Angelidaki et al., 1993). in the model, the substrate is described by its composition of basic organic components, i.e., car...

  18. Solvent-tolerant bioconversion : Construction and analysis of a phenol producing Pseudomonas putida S12

    NARCIS (Netherlands)

    Wierckx, N.J.P.

    2009-01-01

    Organic chemicals play a fundamental role in modern civilization. Today, almost all of these chemicals are produced from oil. This leads to pollution and creates a dependency on often politically unstable oil producing countries. It is possible to make the same chemicals from sugar, using

  19. Solvent-tolerant bioconversion: Construction and analysis of a phenol producing Pseudomonas putida S12

    OpenAIRE

    Wierckx, N.J.P.

    2009-01-01

    Organic chemicals play a fundamental role in modern civilization. Today, almost all of these chemicals are produced from oil. This leads to pollution and creates a dependency on often politically unstable oil producing countries. It is possible to make the same chemicals from sugar, using microorganisms. Sugar is produced from plants, and is therefore an environmentally friendlier and almost inexhaustible resource. Unfortunately many interesting chemicals are toxic to microorganims at low con...

  20. Bioconversion of wastewater from sweet potato starch production to Paenibacillus polymyxa biofertilizer for tea plants.

    Science.gov (United States)

    Xu, Shengjun; Bai, Zhihui; Jin, Bo; Xiao, Runlin; Zhuang, Guoqiang

    2014-02-28

    Wastewater from the sweet potato starch industry is a large source of nutrient-rich substrates. We assessed whether this wastewater could be used to produce Paenibacillus polymyxa biofertilizer for foliar application to tea trees. Using the central composite design methods we experientially determined that the optimal culture conditions for P. polymyxa were pH, 6.5; temperature, 29.0 °C; and incubation time, 16 h. Under these conditions, a maximum biomass of 9.7 × 10(9) cfu/mL was achieved. We then conducted a yearlong field investigation to determine the effect of P. polymyxa biofertilizer on the growth of tea plants (Camellia sinensis). Tea yield, quantity of water extract, and tea polyphenol levels were significantly higher after foliar application of the biofertilizer compared to that in the controls by an average of 16.7%, 6.3%, and 10.4%, respectively. This approach appears to be technically feasible for organic tea production, and is an environmentally friendly way to utilize wastewater.

  1. Butanol production by bioconversion of cheese whey in a continuous packed bed reactor.

    Science.gov (United States)

    Raganati, F; Olivieri, G; Procentese, A; Russo, M E; Salatino, P; Marzocchella, A

    2013-06-01

    Butanol production by Clostridium acetobutylicum DSM 792 fermentation was investigated. Unsupplemented cheese whey was adopted as renewable feedstock. The conversion was successfully carried out in a biofilm packed bed reactor (PBR) for more than 3 months. The PBR was a 4 cm ID, 16 cm high glass tube with a 8 cm bed of 3mm Tygon rings, as carriers. It was operated at the dilution rate between 0.4h(-1) and 0.94 h(-1). The cheese whey conversion process was characterized in terms of metabolites production (butanol included), lactose conversion and biofilm mass. Under optimized conditions, the performances were: butanol productivity 2.66 g/Lh, butanol concentration 4.93 g/L, butanol yield 0.26 g/g, butanol selectivity of the overall solvents production 82 wt%. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Bioconversion of apple pomace into a nutritionally enriched substrate by Candida utilis and Pleurotus ostreatus

    DEFF Research Database (Denmark)

    Villas-Bôas, Silas Granato; Esposito, E.; de Mendonca, M.M.

    2003-01-01

    , into an enriched substrate with increased digestibility for use as ruminant feed. After C. utilis fermentation, the protein level increased 100% and the mineral content 60%, accompanied by 8.2% of increase in the digestibility. The level of free sugars decreased 97% after substrate supplementation with ammonium...... the fermentation with P. ostreatus alone due to pectin and hemicellulose degradation. Considering the time required for fermentation, the C. utilis treatment was the most efficient treatment to convert apple pomace into a more nutritive substrate for ruminant feed....

  3. Bioconversion of nitrogen in an eco-technical system for egg production

    Directory of Open Access Journals (Sweden)

    A. Gencheva

    2015-03-01

    Full Text Available Abstract. The present paper aims to assess nitrogen circulation in an eco-technical system for egg production. The experiments were conducted in modelled conditions in an anthropogenic ecosystem of the “mesocosm” type, in which the unit of the bio-consumers and three eco-technological chains modelling the unit of the bio-decomposers are modelled: manure storing for decontamination /a recommendation on good farming practices/, composting and anaerobic decomposition in an installation for biogas production. A new criterion was implemented for the assessment of the chemical heterogeneity in the biogenic nitrogen cycle in the modified trophic chain – retention coefficient /k/, which is defined as the ratio of nitrogen introduced into the system / nitrogen content in the feed: its quantity in the secondary biological production x 100. The chemical heterogeneity at the level of organisms /differences in the individual components of eggs/ and at the biocenotic level is established. The biogenic nitrogen cycle in the eco-technical chain for egg production is characterized by an uneven distribution in both products of the outflow. The largest amount of nitrogen is found in the egg whites (k = 0.45, while it decreases significantly in egg yolks (k = 0.17 and reaches k = 0.03 in the egg shell, a.k.a. heterogeneity on the level of organisms is established. The nitrogen compounds introduced through the feed ration are concentrated in manure (k = 25.33. Losses of nitrogen are established in two of the manure utilization technologies. The quantity of /k/ in the compost is 20.32, a.k.a. the loss of nitrogen compounds is 19.8%. The biggest losses are found in manure storage; according to the recommendations on good farming practices (k = 18.82 or the reduction of nitrogen is 25.7% compared with fresh manure. Due to redistribution of the chemical elements /a significant part of C, H and O are included in biogas/, there is nitrogen concentration in bio slime – k = 35.85 or 41.5% more than in fresh manure. When separated nitrogen is concentrated in the liquid fraction (k = 31.19, while in the solid phase k = 4.67 is established.

  4. Bioconversion of waste office paper to hydrogen using pretreated rumen fluid inoculum.

    Science.gov (United States)

    Botta, Lívia Silva; Ratti, Regiane Priscila; Sakamoto, Isabel Kimiko; Ramos, Lucas Rodrigues; Silva, Edson Luiz; Varesche, Maria Bernadete Amâncio

    2016-12-01

    In this study, a microbial consortium from an acid-treated rumen fluid was used to improve the yields of H 2 production from paper residues in batch reactors. The anaerobic batch reactors, which contained paper and cellulose, were operated under three conditions: (1) 0.5 g paper/L, (2) 2 g paper/L, and (3) 4 g paper/L. Cellulase was added to promote the hydrolysis of paper to soluble sugars. The H 2 yields were 5.51, 4.65, and 3.96 mmol H 2 /g COD, respectively, with substrate degradation ranging from 56 to 65.4 %. Butyric acid was the primary soluble metabolite in the three reactors, but pronounced solventogenesis was detected in the reactors incubated with increased paper concentrations (2.0 and 4.0 g/L). A substantial prevalence of Clostridium acetobutylicum (99 % similarity) was observed in the acid-treated rumen fluid, which has been recognized as an efficient H 2 -producing strain in addition to ethanol and n-butanol which were also detected in the reactors.

  5. Bioconversion of paper mill sludge to bioethanol in the presence of accelerants or hydrogen peroxide pretreatment.

    Science.gov (United States)

    Gurram, Raghu Nandan; Al-Shannag, Mohammad; Lecher, Nicholas Joshua; Duncan, Shona M; Singsaas, Eric Lawrence; Alkasrawi, Malek

    2015-09-01

    In this study we investigated the technical feasibility of convert paper mill sludge into fuel ethanol. This involved the removal of mineral fillers by using either chemical pretreatment or mechanical fractionation to determine their effects on cellulose hydrolysis and fermentation to ethanol. In addition, we studied the effect of cationic polyelectrolyte (as accelerant) addition and hydrogen peroxide pretreatment on enzymatic hydrolysis and fermentation. We present results showing that removing the fillers content (ash and calcium carbonate) from the paper mill sludge increases the enzymatic hydrolysis performance dramatically with higher cellulose conversion at faster rates. The addition of accelerant and hydrogen peroxide pretreatment further improved the hydrolysis yields by 16% and 25% (g glucose / g cellulose), respectively with the de-ashed sludge. The fermentation process of produced sugars achieved up to 95% of the maximum theoretical ethanol yield and higher ethanol productivities within 9h of fermentation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Thermostable Alcohol Dehydrogenase from Thermococcus kodakarensis KOD1 for Enantioselective Bioconversion of Aromatic Secondary Alcohols

    Science.gov (United States)

    Wu, Xi; Zhang, Chong; Orita, Izumi; Imanaka, Tadayuki

    2013-01-01

    A novel thermostable alcohol dehydrogenase (ADH) showing activity toward aromatic secondary alcohols was identified from the hyperthermophilic archaeon Thermococcus kodakarensis KOD1 (TkADH). The gene, tk0845, which encodes an aldo-keto reductase, was heterologously expressed in Escherichia coli. The enzyme was found to be a monomer with a molecular mass of 31 kDa. It was highly thermostable with an optimal temperature of 90°C and a half-life of 4.5 h at 95°C. The apparent Km values for the cofactors NAD(P)+ and NADPH were similar within a range of 66 to 127 μM. TkADH preferred secondary alcohols and accepted various ketones and aldehydes as substrates. Interestingly, the enzyme could oxidize 1-phenylethanol and its derivatives having substituents at the meta and para positions with high enantioselectivity, yielding the corresponding (R)-alcohols with optical purities of greater than 99.8% enantiomeric excess (ee). TkADH could also reduce 2,2,2-trifluoroacetophenone to (R)-2,2,2-trifluoro-1-phenylethanol with high enantioselectivity (>99.6% ee). Furthermore, the enzyme showed high resistance to organic solvents and was particularly highly active in the presence of H2O–20% 2-propanol and H2O–50% n-hexane or n-octane. This ADH is expected to be a useful tool for the production of aromatic chiral alcohols. PMID:23354700

  7. Bioconversion from crude glycerin by Xanthomonas campestris 2103: xanthan production and characterization

    Directory of Open Access Journals (Sweden)

    L. V. Brandão

    2013-12-01

    Full Text Available The production and rheological properties of xanthan gum from crude glycerin fermentation, a primary by-product of the biodiesel industry with environmental and health risks, were evaluated. Batch fermentations (28 °C/250 rpm /120 h were carried out using crude glycerin, 0.01% urea and 0.1% KH2PO4, (% w/v, and compared to a sucrose control under the same operational conditions, using Xanthomonas campestris strain 2103 isolate from Brazil. Its maximal production by crude glycerin fermentation was 7.23±0.1 g·L-1 at 120 h, with an apparent viscosity of 642.57 mPa·s, (2 % w/v, 25 °C, 25 s-1, 70% and 30% higher than from sucrose fermentation, respectively. Its molecular weight varied from 28.2 to 36.2×10(6 Da. The Ostwald-de-Waele model parameters (K and n indicated a pseudoplastic behavior at all concentrations (0.5 to 2.0 %, w/v and temperatures (25-85 °C, while its consistency index indicated promising rheological properties for drilling fluid applications. Therefore, crude glycerin has potential as a cost-effective and alternative substrate for non-food grade xanthan production.

  8. Bioconversion of Waste Fiber Sludge to Bacterial Nanocellulose and Use for Reinforcement of CTMP Paper Sheets

    Directory of Open Access Journals (Sweden)

    Genqiang Chen

    2017-09-01

    Full Text Available Utilization of bacterial nanocellulose (BNC for large-scale applications is restricted by low productivity in static cultures and by the high cost of the medium. Fiber sludge, a waste stream from pulp and paper mills, was enzymatically hydrolyzed to sugar, which was used for the production of BNC by the submerged cultivation of Komagataeibacter xylinus. Compared with a synthetic glucose-based medium, the productivity of purified BNC from the fiber sludge hydrolysate using shake-flasks was enhanced from 0.11 to 0.17 g/(L × d, although the average viscometric degree of polymerization (DPv decreased from 6760 to 6050. The cultivation conditions used in stirred-tank reactors (STRs, including the stirring speed, the airflow, and the pH, were also investigated. Using STRs, the BNC productivity in fiber-sludge medium was increased to 0.32 g/(L × d and the DPv was increased to 6650. BNC produced from the fiber sludge hydrolysate was used as an additive in papermaking based on the chemithermomechanical pulp (CTMP of birch. The introduction of BNC resulted in a significant enhancement of the mechanical strength of the paper sheets. With 10% (w/w BNC in the CTMP/BNC mixture, the tear resistance was enhanced by 140%. SEM images showed that the BNC cross-linked and covered the surface of the CTMP fibers, resulting in enhanced mechanical strength.

  9. Bioconversion of oxygen-pretreated Kraft lignin to microbial lipid with oleaginous Rhodococcus opacus DSM 1069

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Zhen [Hunan Univ. Changsha (China); Zeng, Guangming [Hunan Univ. Changsha (China); Huang, Fang [Georgia Inst. of Technology, Atlanta, GA (United States); Kosa, Matyas [Georgia Inst. of Technology, Atlanta, GA (United States); Huang, Danlian [Hunan Univ. Changsha (China); Ragauskas, Arthur J. [Georgia Inst. of Technology, Atlanta, GA (United States); Univ. of Tennessee, Knoxville, TN (United States)

    2015-04-09

    Kraft lignin (KL) from black liquor is an abundantly available, inexpensive aromatic resource that is regarded as a low value compound by the pulp and paper industry, necessitating the development of new applications.

  10. Multi-scale individual-based model of microbial and bioconversion dynamics in aerobic granular sludge.

    Science.gov (United States)

    Xavier, Joao B; De Kreuk, Merle K; Picioreanu, Cristian; Van Loosdrecht, Mark C M

    2007-09-15

    Aerobic granular sludge is a novel compact biological wastewater treatment technology for integrated removal of COD (chemical oxygen demand), nitrogen, and phosphate charges. We present here a multiscale model of aerobic granular sludge sequencing batch reactors (GSBR) describing the complex dynamics of populations and nutrient removal. The macro scale describes bulk concentrations and effluent composition in six solutes (oxygen, acetate, ammonium, nitrite, nitrate, and phosphate). A finer scale, the scale of one granule (1.1 mm of diameter), describes the two-dimensional spatial arrangement of four bacterial groups--heterotrophs, ammonium oxidizers, nitrite oxidizers, and phosphate accumulating organisms (PAO)--using individual based modeling (IbM) with species-specific kinetic models. The model for PAO includes three internal storage compounds: polyhydroxyalkanoates (PHA), poly phosphate, and glycogen. Simulations of long-term reactor operation show how the microbial population and activity depends on the operating conditions. Short-term dynamics of solute bulk concentrations are also generated with results comparable to experimental data from lab scale reactors. Our results suggest that N-removal in GSBR occurs mostly via alternating nitrification/denitrification rather than simultaneous nitrification/denitrification, supporting an alternative strategy to improve N-removal in this promising wastewater treatment process.

  11. Bioconversion of Agricultural Waste to Ethanol by SSF Using Recombinant Cellulase from Clostridium thermocellum

    Directory of Open Access Journals (Sweden)

    Ruchi Mutreja

    2011-01-01

    Full Text Available The effect of different pretreatment methods, temperature, and enzyme concentration on ethanol production from 8 lignocellulosic agrowaste by simultaneous saccharification and fermentation (SSF using recombinant cellulase and Saccharomyces cerevisiae were studied. Recombinant cellulase was isolated from E. coli BL21 cells transformed with CtLic26A-Cel5-CBM11 full-length gene from Clostridium thermocellum and produced in both batch and fed-batch processes. The maximum cell OD and specific activity in batch mode were 1.6 and 1.91 U/mg, respectively, whereas in the fed-batch mode, maximum cell OD and specific activity were 3.8 and 3.5 U/mg, respectively, displaying a 2-fold increase. Eight substrates, Syzygium cumini (jamun, Azadirachta indica (neem, Saracens indica (asoka, bambusa dendrocalmus (bamboo, Populas nigra (poplar, Achnatherum hymenoides (wild grass, Eucalyptus marginata (eucalyptus, and Mangifera indica (mango, were subjected to SSF. Of three pretreatments, acid, alkali, and steam explosion, acid pretreatment Syzygium cumini (Jamun at 30°C gave maximum ethanol yield of 1.42 g/L.

  12. Bioconversion of Agricultural Waste to Ethanol by SSF Using Recombinant Cellulase from Clostridium thermocellum.

    Science.gov (United States)

    Mutreja, Ruchi; Das, Debasish; Goyal, Dinesh; Goyal, Arun

    2011-01-01

    The effect of different pretreatment methods, temperature, and enzyme concentration on ethanol production from 8 lignocellulosic agrowaste by simultaneous saccharification and fermentation (SSF) using recombinant cellulase and Saccharomyces cerevisiae were studied. Recombinant cellulase was isolated from E. coli BL21 cells transformed with CtLic26A-Cel5-CBM11 full-length gene from Clostridium thermocellum and produced in both batch and fed-batch processes. The maximum cell OD and specific activity in batch mode were 1.6 and 1.91 U/mg, respectively, whereas in the fed-batch mode, maximum cell OD and specific activity were 3.8 and 3.5 U/mg, respectively, displaying a 2-fold increase. Eight substrates, Syzygium cumini (jamun), Azadirachta indica (neem), Saracens indica (asoka), bambusa dendrocalmus (bamboo), Populas nigra (poplar), Achnatherum hymenoides (wild grass), Eucalyptus marginata (eucalyptus), and Mangifera indica (mango), were subjected to SSF. Of three pretreatments, acid, alkali, and steam explosion, acid pretreatment Syzygium cumini (Jamun) at 30°C gave maximum ethanol yield of 1.42 g/L.

  13. Bioconversion of glycerol for bioethanol production using isolated Escherichia coli SS1

    Directory of Open Access Journals (Sweden)

    Sheril Norliana Suhaimi

    2012-06-01

    Full Text Available 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.

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

    Science.gov (United States)

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

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

  15. Effect of pelleting on the recalcitrance and bioconversion of dilute-acid pretreated corn stover

    Energy Technology Data Exchange (ETDEWEB)

    Allison E Ray; Amber Hoover; Gary Gresham

    2012-07-01

    Background: Knowledge regarding the performance of densified biomass in biochemical processes is limited. The effects of densification on biochemical conversion are explored here. Methods: Pelleted corn stover samples were generated from bales that were milled to 6.35 mm. Low-solids acid pretreatment and simultaneous saccharification and fermentation were performed to evaluate pretreatment efficacy and ethanol yields achieved for pelleted and ground stover (6.35 mm and 2 mm) samples. Both pelleted and 6.35-mm ground stover were evaluated using a ZipperClave® reactor under high-solids, process-relevant conditions for multiple pretreatment severities (Ro), followed by enzymatic hydrolysis of the washed, pretreated solids. Results: Monomeric xylose yields were significantly higher for pellets (approximately 60%) than for ground formats (approximately 38%). Pellets achieved approximately 84% of theoretical ethanol yield (TEY); ground stover formats had similar profiles, reaching approximately 68% TEY. Pelleting corn stover was not detrimental to pretreatment efficacy for both low- and high-solids conditions, and even enhanced ethanol yields.

  16. Bioconversion and enzymatic activities of neurospora sitophila grown under solid state and submerged fermentation on Sago Hamps

    International Nuclear Information System (INIS)

    Shojaosadati, S. A.; Vikineswary, S.; Looi, C. C.

    2000-01-01

    N.Sitophila was grown under controlled conditions of solid state and submerged fermentation on Sago Hampas. The optimum conditions of protein enrichment previously established for sugar beet pulp was used for this study. Under this condition the protein content of Sago Hampas under solid state increased from 1.4 to 14.45% (W/W) whereas for Sago Hampas and Sago starch, the protein content under submerged condition increased from 1.4% (W/W) and 0.7% (W/W) to 18.56% (W/W) and 43/16% (W/W) based on dry weight of product respectively. The cellulase, a-amylase and glucoamylase activities of N.Sitophila under solid state condition on Sago Hampas were, 9.0, 0.6 and 11.8 U/g of wet fermented solid respectively. the enzymatic activities were also measured under submerged fermentation using both Sago Hampas and Sago starch as substrate

  17. Process development studies on the bioconversion of cellulose and production of ethanol. Progress report, September 1, 1978

    Energy Technology Data Exchange (ETDEWEB)

    Wilke, C.R.

    1978-09-01

    Progress is reported in studies on the pretreatment of cellulosic materials to facilitate enzymatic hydrolysis, sulfuric acid hydrolysis, investigation of the Purdue processing scheme including an economic analysis, and the fermentability of the enzymatic hydrolyzate. Progress is also reported on enzyme fermentation studies, hydrolysis reactor development, and utilization of hemicellulose sugars. (JSR)

  18. Bioconversion of garden waste, kitchen waste and cow dung into value-added products using earthworm Eisenia fetida.

    Science.gov (United States)

    Wani, K A; Mamta; Rao, R J

    2013-04-01

    Solid waste management is a worldwide problem and it is becoming more and more complicated day by day due to rise in population, industrialization and changes in our life style. Transformation of industrial sludges into vermicompost is of double interest: on the one hand, a waste is converted into value added product, and, on the other, it controls a pollutant that is a consequence of increasing industrialization. Garden waste, kitchen waste and cow dung were subjected to recycle through vermicomposting by using the epigeic earthworm Eisenia fetida under field conditions. The pH, moisture content, total organic carbon, humus, nitrogen, phosphorous and potassium in vermicompost was analysed. It was found that moisture content, total organic carbon, humus, nitrogen, phosphorous and potassium was high in cow dung, followed by kitchen waste and garden waste. This study clearly indicates that vermicomposting of garden waste, kitchen waste and cow dung can not only produce a value added produce (vermicomposting) but at the same time reduce the quantity of waste.

  19. Vanillin-bioconversion and bioengineering of the most popular plant flavor and its de novo biosynthesis in the vanilla orchid.

    Science.gov (United States)

    Gallage, Nethaji J; Møller, Birger Lindberg

    2015-01-01

    In recent years, biotechnology-derived production of flavors and fragrances has expanded rapidly. The world's most popular flavor, vanillin, is no exception. This review outlines the current state of biotechnology-based vanillin synthesis with the use of ferulic acid, eugenol, and glucose as substrates and bacteria, fungi, and yeasts as microbial production hosts. The de novo biosynthetic pathway of vanillin in the vanilla orchid and the possible applied uses of this new knowledge in the biotechnology-derived and pod-based vanillin industries are also highlighted. Copyright © 2015 The Author. Published by Elsevier Inc. All rights reserved.

  20. Vanillin - Bioconversion and Bioengineering of the most popular plant flavour and its de novo biosynthesis in the vanilla orchid.

    Science.gov (United States)

    Gallage, Nethaji J; Moeller, Birger Lindberg

    2014-09-30

    During recent years, biotechnology derived production of flavours and fragrances have expanded rapidly. The world's most popular flavour vanillin is no exception. This review outlines the current state of biotechnology-based vanillin synthesis with the use of ferulic acid, eugenol and glucose as substrates and bacteria, fungi and yeasts as microbial production hosts. The elucidated de novo biosynthetic pathway of vanillin in the vanilla orchid and the possible applied uses of this new knowledge in the biotechnology derived and pod-based vanillin industries are also highlighted. © The Author 2014. Published by the Molecular Plant Shanghai Editorial Office in association with Oxford University Press on behalf of CSPB and IPPE, SIBS, CAS.

  1. Advanced anaerobic bioconversion of lignocellulosic waste for bioregenerative life support following thermal water treatment and biodegradation by Fibrobacter succinogenes.

    Science.gov (United States)

    Lissens, Geert; Verstraete, Willy; Albrecht, Tobias; Brunner, Gerd; Creuly, Catherine; Seon, Jerome; Dussap, Gilles; Lasseur, Christophe

    2004-06-01

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

  2. CONCEPT OF IN-OIL PROJECT BASED ON BIOCONVERSION OF BY-PRODUCTS FROM FOOD PROCESSING INDUSTRY

    Directory of Open Access Journals (Sweden)

    Wojciech Czekała

    2017-09-01

    The main assumption of the project is based on the introduction of by-products from the food processing industry to feeding with larvae of H. illucens. Biomass of insect larvae will then be processed into products that will be used for feed and energy purposes.

  3. A systematic methodology to extend the applicability of a bioconversion model for the simulation of various co-digestion scenarios

    DEFF Research Database (Denmark)

    Kovalovszki, Adam; Alvarado-Morales, Merlin; Fotidis, Ioannis

    2017-01-01

    Detailed simulation of anaerobic digestion (AD) requires complex mathematical models and the optimization of numerous model parameters. By performing a systematic methodology and identifying parameters with the highest impact on process variables in a well-established AD model, its applicability...... was extended to various co-digestion scenarios. More specifically, the application of the step-by-step methodology led to the estimation of a general and reduced set of parameters, for the simulation of scenarios where either manure or wastewater were co-digested with different organic substrates. Validation...... experimental data quite well, indicating that it offers a reliable reference point for future simulations of anaerobic co-digestion scenarios....

  4. A feasibility study on the bioconversion of CO2 and H2 to biomethane by gas sparging through polymeric membranes.

    Science.gov (United States)

    Díaz, I; Pérez, C; Alfaro, N; Fdz-Polanco, F

    2015-06-01

    In this study, the potential of a pilot hollow-fiber membrane bioreactor for the conversion of H2 and CO2 to CH4 was evaluated. The system transformed 95% of H2 and CO2 fed at a maximum loading rate of 40.2 [Formula: see text] and produced 0.22m(3) of CH4 per m(3) of H2 fed at thermophilic conditions. H2 mass transfer to the liquid phase was identified as the limiting step for the conversion, and kLa values of 430h(-1) were reached in the bioreactor by sparging gas through the membrane module. A simulation showed that the bioreactor could upgrade biogas at a rate of 25m(3)/mR(3)d, increasing the CH4 concentration from 60 to 95%v. This proof-of-concept study verified that gas sparging through a membrane module can efficiently transfer H2 from gas to liquid phase and that the conversion of H2 and CO2 to biomethane is feasible on a pilot scale at noteworthy load rates. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Bioconversion of biomass residue from the cultivation of pea sprouts on spent Pleurotus sajor-caju compost employing Lumbricus rubellus

    Directory of Open Access Journals (Sweden)

    Azizi Abu Bakar

    2012-11-01

    Full Text Available Vermicomposting is a green technology for the purpose of nutrient enrichment from a variety of organic waste products. In this study, saw dust-based spent mushroom compost (SMC, an organic waste and biomass residue, was used as a medium for the cultivation of pea sprouts. After harvesting the pea sprouts, the growth medium was reused to culture earthworms, Lumbricus rubellus. The culturing activity was conducted for 50 days without any pre-composting or thermocomposting. Thus duration of vermicomposting process was shortened as opposed to previous work on vermicomposting of saw dust-based SMC (no amendment for 70 days. The culturing treatments were conducted in triplicate, including one treatment without earthworms as the control. The analysis showed that concentrations of macronutrients in vermicompost were higher compared to controls, in which N = 4.12%, P = 2.07% and K = 1.56%. The C:N ratio was 11.77, which indicates a stabilisation and maturity of the organic waste compost, compared with the C:N ratio for the control, which was 59.34. At the end of the experiment, increment of total biomass and number of earthworms were observed and no mortality was recorded. The results suggested that vermicomposting could be used as an environmentally valuable technology to convert saw dust used for mushroom and pea sprouts cultivation into vermicompost or bio-fertiliser by employing L. rubellus.

  6. Bioconversion of methanol to value-added mevalonate by engineered Methylobacterium extorquens AM1 containing an optimized mevalonate pathway.

    Science.gov (United States)

    Zhu, Wen-Liang; Cui, Jin-Yu; Cui, Lan-Yu; Liang, Wei-Fan; Yang, Song; Zhang, Chong; Xing, Xin-Hui

    2016-03-01

    Methylotrophic biosynthesis using methanol as a feedstock is a promising and attractive method to solve the over-dependence of the bioindustry on sugar feedstocks derived from grains that are used for food. In this study, we introduced and engineered the mevalonate pathway into Methylobacterium extorquens AM1 to achieve high mevalonate production from methanol, which could be a platform for terpenoid synthesis. We first constructed a natural operon (MVE) harboring the mvaS and mvaE genes from Enterococcus faecalis as well as an artificial operon (MVH) harboring the hmgcs1 gene from Blattella germanica and the tchmgr gene from Trypanosoma cruzi that encoded enzymes with the highest reported activities. We achieved mevalonate titers of 56 and 66 mg/L, respectively, in flask cultivation. Introduction of the phaA gene from Ralstonia eutropha into the operon MVH increased the mevalonate titer to 180 mg/L, 3.2-fold higher than that of the natural operon MVE. Further modification of the expression level of the phaA gene by regulating the strength of the ribosomal binding site resulted in an additional 20 % increase in mevalonate production to 215 mg/L. A fed-batch fermentation of the best-engineered strain yielded a mevalonate titer of 2.22 g/L, which was equivalent to an overall yield and productivity of 28.4 mg mevalonate/g methanol and 7.16 mg/L/h, respectively. The production of mevalonate from methanol, which is the initial, but critical step linking methanol with valuable terpenoids via methylotrophic biosynthesis, represents a proof of concept for pathway engineering in M. extorquens AM1.

  7. Bioconversion of starch to ethanol in a single-step process by coculture of amylolytic yeasts and Saccharomyces cerevisiae 21

    Energy Technology Data Exchange (ETDEWEB)

    Verma, G.; Singh, D.; Chaudhary, K. [CCS Haryana Agricultural Univ., Hisar (India). Dept. of Biotechnology and Molecular Biology; Nigam, P. [Ulster Univ., Coleraine, Northern Ireland (United Kingdom). School of Applied Biological and Chemical Sciences

    2000-05-01

    Ethanol production by a coculture of Saccharomyces diastaticus and Saccharomyces cerevisiae 21 was 24.8 g/l using raw unhydrolysed starch in a single-step fermentation. This was 48% higher than the yield obtained with the monoculture of S. diastaticus (16.8 g/l). The maximum ethanol fermentation efficiency was achieved (93% of the theoretical value) using 60 g/l starch concentration. In another coculture fermentation with E. capsularis and S. cerevisiae 21, maximum ethanol yield was 16.0 g/l, higher than the yield with the monoculture of Endomycopsis capsularis. In batch fermentations using cocultures maximum ethanol production occurred in 48 h of fermentation at 30{sup o}C using 60 g/l starch. Fermentation efficiency was found lower in a two-step process using {alpha}-amylase and glucoamylase-treated starch. (Author)

  8. Fermentation products of solvent tolerant marine bacterium Moraxella spp. MB1 and its biotechnological applications in salicylic acid bioconversion

    Digital Repository Service at National Institute of Oceanography (India)

    Wahidullah, S.; Naik, D.N.; PrabhaDevi

    As part of a proactive approach to environmental protection, emerging issues with potential impact on the environment is the subject of ongoing investigation. One emerging area of environmental research concerns pharmaceuticals like salicylic acid...

  9. Microalgal carbohydrates: an overview of the factors influencing carbohydrates production, and of main bioconversion technologies for production of biofuels

    DEFF Research Database (Denmark)

    Markou, Giorgos; Angelidaki, Irini; Georgakakis, Dimitris

    2012-01-01

    in research is the cultivation of microalgae for lipids production to generate biodiesel. However, there are several other biological or thermochemical conversion technologies, in which microalgal biomass could be used as substrate. However, the high protein content or the low carbohydrate content...... of the majority of the microalgal species might be a constraint for their possible use in these technologies. Moreover, in the majority of biomass conversion technologies, carbohydrates are the main substrate for production of biofuels. Nevertheless, microalgae biomass composition could be manipulated by several......Microalgal biomass seems to be a promising feedstock for biofuel generation. Microalgae have relative high photosynthetic efficiencies, high growth rates, and some species can thrive in brackish water or seawater and wastewater from the food- and agro-industrial sector. Today, the main interest...

  10. Microalgal carbohydrates. An overview of the factors influencing carbohydrates production, and of main bioconversion technologies for production of biofuels

    Energy Technology Data Exchange (ETDEWEB)

    Markou, Giorgos; Georgakakis, Dimitris [Agricultural Univ. of Athens (Greece). Dept. of Natural Resources Management and Agricultural Engineering; Angelidaki, Irini [Technical Univ. of Denmark, Lyngby (Denmark). Dept. of Environmental Engineering

    2012-11-15

    Microalgal biomass seems to be a promising feedstock for biofuel generation. Microalgae have relative high photosynthetic efficiencies, high growth rates, and some species can thrive in brackish water or seawater and wastewater from the food- and agro-industrial sector. Today, the main interest in research is the cultivation of microalgae for lipids production to generate biodiesel. However, there are several other biological or thermochemical conversion technologies, in which microalgal biomass could be used as substrate. However, the high protein content or the low carbohydrate content of the majority of the microalgal species might be a constraint for their possible use in these technologies. Moreover, in the majority of biomass conversion technologies, carbohydrates are the main substrate for production of biofuels. Nevertheless, microalgae biomass composition could be manipulated by several cultivation techniques, such as nutrient starvation or other stressed environmental conditions, which cause the microalgae to accumulate carbohydrates. This paper attempts to give a general overview of techniques that can be used for increasing the microalgal biomass carbohydrate content. In addition, biomass conversion technologies, related to the conversion of carbohydrates into biofuels are discussed. (orig.)

  11. Cyclodextrin-facilitated bioconversion of 17 beta-estradiol by a phenoloxidase from Mucuna pruriens cell cultures

    NARCIS (Netherlands)

    Woerdenbag, H.J.; Pras, N.; Frijlink, H.W.; Lerk, C.F.; Malingré, T.M.

    1990-01-01

    After complexation with beta-cyclodextrin, the phenolic steroid 17 beta-estradiol could be ortho-hydroxylated into a catechol, mainly 4-hydroxyestradiol, by a phenoloxidase from in vitro grown cells of Mucuna pruriens. By complexation with beta-cyclodextrin the solubility of the steroid increased

  12. New cost-effective bioconversion process of palm kernel cake into bioinsecticides based on Beauveria bassiana and Isaria javanica.

    Science.gov (United States)

    do Nascimento Silva, Jaqueline; Mascarin, Gabriel Moura; Dos Santos Gomes, Isabel Cristina; Tinôco, Ricardo Salles; Quintela, Eliane Dias; Dos Reis Castilho, Leda; Freire, Denise Maria Guimarães

    2018-03-01

    The present study aimed to add value to palm oil by-products as substrates to efficiently produce conidia of Beauveria bassiana and Isaria javanica (Hypocreales: Cordycipitaceae) for biological control of the whitefly Bemisia tabaci (Hemiptera: Aleyrodidae), through a solid-state fermentation process using palm kernel cake and palm fiber as nutrient source and solid matrix, respectively. The optimum culture conditions yielded high concentrations of viable conidia after air-drying, when the fungi were grown on palm kernel cake (B. bassiana 7.65 × 10 9 and I. javanica 2.91 × 10 9  conidia g -1 dry substrate) after 6 days under optimal growth conditions set to 60% substrate moisture and 32 °C. Both fungal strains exhibited high efficacy against third-instar whitefly nymphs, inducing mortality up to 62.9 and 56.6% by B. bassiana and I. javanica, respectively, assessed after 9 days post-application in a screenhouse. Furthermore, we noted that insect mortality was strongly correlated with high atmospheric moisture, while B. bassiana appeared to require shorter accumulative hours under high moisture to kill whitefly nymphs compared to I. javanica. Our results underpin a feasible and cost-effective mass production method for aerial conidia, using palm kernel as the main substrate in order to produce efficacious fungal bioinsecticides against an invasive whitefly species in Brazil. Finally, our fermentation process may offer a sustainable and cost-effective means to produce eco-friendly mycoinsecticides, using an abundant agro-industrial by-product from Brazil that will ultimately assist in the integrated management of agricultural insect pests.

  13. Construction and Optimization of a Heterologous Pathway for Protocatechuate Catabolism in Escherichia coli Enables Bioconversion of Model Aromatic Compounds.

    Science.gov (United States)

    Clarkson, Sonya M; Giannone, Richard J; Kridelbaugh, Donna M; Elkins, James G; Guss, Adam M; Michener, Joshua K

    2017-09-15

    The production of biofuels from lignocellulose yields a substantial lignin by-product stream that currently has few applications. Biological conversion of lignin-derived compounds into chemicals and fuels has the potential to improve the economics of lignocellulose-derived biofuels, but few microbes are able both to catabolize lignin-derived aromatic compounds and to generate valuable products. While Escherichia coli has been engineered to produce a variety of fuels and chemicals, it is incapable of catabolizing most aromatic compounds. Therefore, we engineered E. coli to catabolize protocatechuate, a common intermediate in lignin degradation, as the sole source of carbon and energy via heterologous expression of a nine-gene pathway from Pseudomonas putida KT2440. We next used experimental evolution to select for mutations that increased growth with protocatechuate more than 2-fold. Increasing the strength of a single ribosome binding site in the heterologous pathway was sufficient to recapitulate the increased growth. After optimization of the core pathway, we extended the pathway to enable catabolism of a second model compound, 4-hydroxybenzoate. These engineered strains will be useful platforms to discover, characterize, and optimize pathways for conversions of lignin-derived aromatics. IMPORTANCE Lignin is a challenging substrate for microbial catabolism due to its polymeric and heterogeneous chemical structure. Therefore, engineering microbes for improved catabolism of lignin-derived aromatic compounds will require the assembly of an entire network of catabolic reactions, including pathways from genetically intractable strains. Constructing defined pathways for aromatic compound degradation in a model host would allow rapid identification, characterization, and optimization of novel pathways. We constructed and optimized one such pathway in E. coli to enable catabolism of a model aromatic compound, protocatechuate, and then extended the pathway to a related compound, 4-hydroxybenzoate. This optimized strain can now be used as the basis for the characterization of novel pathways. Copyright © 2017 American Society for Microbiology.

  14. Bioconversion of glycerol to 1,3-propanediol in thin stillage-based media by engineered Lactobacillus panis PM1.

    Science.gov (United States)

    Kang, Tae Sun; Korber, Darren R; Tanaka, Takuji

    2014-04-01

    Thin stillage (TS) is a waste residue that remains after bioethanol production, and its disposal reflects the high costs of bioethanol production. Thus, the development of cost-effective ways to process TS is a pending issue in bioethanol plants. The aim of this study was to evaluate the utilization of TS for the production of the valuable chemical, 1,3-propanediol (1,3-PDO), by Lactobacillus panis PM1. Different fermentation parameters, including temperature, pH and strains [wild-type and a recombinant strain expressing a NADPH-dependent aldehyde reductase (YqhD) gene] were tested in batch and fed-batch cultivations. The highest 1,3-PDO concentration (12.85 g/L) and yield (0.84 g/g) were achieved by batch fermentation at pH-4.5/30 °C by the YqhD recombinant strain. Furthermore, pH-controlled batch fermentation reduced the total fermentation period, resulting in the maximal 1,3-PDO concentration of 16.23 g/L and yield of 0.72 g/g in TS without an expensive nutrient or nitrogen (e.g., yeast extract, beef extract, and peptone) supplementation. The addition of two trace elements, Mg(2+) and Mn(2+), in TS increased 1,3-PDO yield (0.74 g/g) without 3-hydroxypropionaldehyde production, the only intermediate of 1,3-PDO biosynthetic pathway in L. panis PM1. Our results suggest that L. panis PM1 can offer a cost-effective process that utilizes the TS to produce a value-added chemical, 1,3-PDO.

  15. Bioconversion of different sizes of microcrystalline cellulose pretreated by microwave irradiation with/without NaOH

    International Nuclear Information System (INIS)

    Peng, Huadong; Chen, Hongzhang; Qu, Yongshui; Li, Hongqiang; Xu, Jian

    2014-01-01

    Highlights: • High concentration of alkali or temperature was necessary in cellulose degradation. • Effects of alkali pretreatment could be enhanced with the addition of microwave irradiation. • The structures diversities of microcrystalline cellulose were eliminated in the fermentation. • The significance of particle size and treat condition varied with reaction time. - Abstract: The process of microwave irradiation (MWI) pretreatment on microcrystalline cellulose (MCC) with different sizes with/without NaOH was investigated on the variation of the ratio of degradated solid residue (R DS ), particle size, crystallinity index (CrI), crystallite size (Sc) and specific surface area (SSA). High concentration of alkali or high temperature was necessary in dissolving or decomposing the cellulose. Appropriate pretreatment severity eliminated the effects of structural diversities in feedstocks, which led to convergence in the ethanol fermentation. After the reaction proceeded to 120 h, the samples could be converted to glucose completely and the highest ethanol yield of the theoretical was 58.91% for all the samples pretreated by the combined treatment of MWI and NaOH. In addition, the statistical analysis implied that when reaction time got to 24 h, particle size and pretreatment condition affected much more significant than other factors

  16. Bioconversion of isoflavone glycosides to aglycones, mineral bioavailability and vitamin B complex in fermented soymilk by probiotic bacteria and yeast.

    Science.gov (United States)

    Rekha, C R; Vijayalakshmi, G

    2010-10-01

    To study the role of β-glucosidase producing probiotic bacteria and yeast in the biotransformation of isoflavone glycosides to aglycones, mineral bioavailability and vitamin B complex in fermented soymilk. Five isolates of probiotic lactic acid bacteria (LAB), Lactobacillus acidophilus B4496, Lactobacillus bulgaricus CFR2028, Lactobacillus casei B1922, Lactobacillus plantarum B4495 and Lactobacillus fermentum B4655 with yeast Saccharomyces boulardii were used to ferment soymilk to obtain the bioactive isoflavones, genistein and daidzein. High-performance liquid chromatography was used to analyse the concentration of isoflavones. Bioactive aglycones genistein and daidzein after 24 and 48 h of fermentation ranged from 97.49 to 98.49% and 62.71 to 92.31% respectively with different combinations of LAB with yeast. Increase in bioavailability of minerals and vitamin B complex were also observed in fermented soymilk. LAB in combination with yeast S. boulardii has great potential for the enrichment of bioactive isoflavones, enhancing the viability of LAB strains, decreasing the antinutrient phytic acid and increasing the mineral bioavailability in soymilk fermentation. Fermentation of soymilk with probiotic organisms improves the bioavailability of isoflavones, assists in digestion of protein, provides more soluble calcium, enhances intestinal health and supports immune system. Increased isoflavone aglycone content in fermented soymilk improves the biological functionality of soymilk. © 2010 The Authors. Journal compilation © 2010 The Society for Applied Microbiology.

  17. Simultaneous saccharification of inulin and starch using commercial glucoamylase and the subsequent bioconversion to high titer sorbitol and gluconic acid.

    Science.gov (United States)

    An, Kehong; Hu, Fengxian; Bao, Jie

    2013-12-01

    A new bioprocess for production of sorbitol and gluconic acid from two low-cost feedstocks, inulin and cassava starch, using a commercially available enzyme was proposed in this study. The commercial glucoamylase GA-L NEW from Genencor was found to demonstrate a high inulinase activity for hydrolysis of inulin into fructose and glucose. The glucoamylase was used to replace the expensive and not commercially available inulinase enzyme for simultaneous saccharification of inulin and starch into high titer glucose and fructose hydrolysate. The glucose and fructose in the hydrolysate were converted into sorbitol and gluconic acid using immobilized whole cells of the recombinant Zymomonas mobilis strain. The high gluconic acid concentration of 193 g/L and sorbitol concentration of 180 g/L with the overall yield of 97.3 % were obtained in the batch operations. The present study provided a practical production method of sorbitol and gluconic acid from low cost feedstocks and enzymes.

  18. Bioconversion of garden waste, kitchen waste and cow dung into value-added products using earthworm Eisenia fetida

    Science.gov (United States)

    Wani, K.A.; Mamta; Rao, R.J.

    2013-01-01

    Solid waste management is a worldwide problem and it is becoming more and more complicated day by day due to rise in population, industrialization and changes in our life style. Transformation of industrial sludges into vermicompost is of double interest: on the one hand, a waste is converted into value added product, and, on the other, it controls a pollutant that is a consequence of increasing industrialization. Garden waste, kitchen waste and cow dung were subjected to recycle through vermicomposting by using the epigeic earthworm Eisenia fetida under field conditions. The pH, moisture content, total organic carbon, humus, nitrogen, phosphorous and potassium in vermicompost was analysed. It was found that moisture content, total organic carbon, humus, nitrogen, phosphorous and potassium was high in cow dung, followed by kitchen waste and garden waste. This study clearly indicates that vermicomposting of garden waste, kitchen waste and cow dung can not only produce a value added produce (vermicomposting) but at the same time reduce the quantity of waste. PMID:23961230

  19. Requirements of Saccharomyces Cerevisiae,Y 10 for Bioconversion of Lignocellulose Substrates to Ethanol under Simultaneous Saccharification and Fermentation Processes

    International Nuclear Information System (INIS)

    Rady, A.H.; Younis, N.A.; Sidkey, N.M.; Ouda, S.M.

    2006-01-01

    Ethanol production increased gradually with increasing the incubation period to a maximum value at 72 hrs for rice straw, bagasse and CHW (Cellulosic hospital wastes) under simultaneous saccharification and fermentation technique (SSF). bagasse was the best substrate for maximum production . maximum Values of ethanol were recorded when crude cellulses were 1.79, 0.597 and 1.19 (FPU /ml fermentation medium) for substrates respectively. the optimum inoculum number of yeast was (9x10 8 free cells / ml for rice straw, (1.2x10 9 cells/ml) of immobilized and free yeast for bagasse and CHW respectively. Maximum yield was recorded with ph 5 at 30 degree C for the three substrates. Fe SO 4 .7H 2 O(0.05%) increased ethanol production from pretreated bagasse and CHW .L-Iysine increased the productivity for both bagasse and CHW. molasses (9 g/l) achieved the highest productivity from treated rice straw, while thiamine B1 (100 and 200 ppm) for treated bagsse and CHW respectively. Gamma rays at doses 0.05 and 0.8 K.Gy increased ethanol yield 7.5 and 2 % for treated bagasse and CHW respectively. Highest values recorded at 300,200 and 100 rpm. for treated rice straw, bagasse and CHW, respectively

  20. The value of surrogate markers to monitor cholesterol absorption, synthesis and bioconversion to bile acids under lipid lowering therapies.

    Science.gov (United States)

    Stellaard, Frans; von Bergmann, Klaus; Sudhop, Thomas; Lütjohann, Dieter

    2017-05-01

    Regulation of cholesterol (Chol) homeostasis is controlled by three main fluxes, i.e. intestinal absorption, de novo synthesis (ChS) and catabolism, predominantly as bile acid synthesis (BAS). High serum total Chol and LDL-Chol concentrations in particular are considered risk factors and markers for the development of atherosclerosis. Pharmaceutical treatments to lower serum Chol have focused on reducing absorption or ChS and increasing BAS. Monitoring of these three parameters is complex involving isotope techniques, cholesterol balance experiments and advanced mass spectrometry based analysis methods. Surrogate markers were explored that require only one single fasting blood sample collection. These markers were validated in specific, mostly physiological conditions and during statin treatment to inhibit ChS. They were also applied under cholesterol absorption restriction, but were not validated in this condition. We retrospectively evaluated the use of serum campesterol (Camp), sitosterol (Sit) and cholestanol (Cholol) as markers for cholesterol absorption, lathosterol (Lath) as marker for ChS and 7α-hydroxycholesterol (7α-OH-Ch) and 27-hydroxycholesterol (27-OH-Ch) as markers for BAS under conditions of Chol absorption restriction. Additionally, their values were corrected for Chol concentration (R_sterol or oxysterols). Thirty-seven healthy male omnivore subjects were studied under treatments with placebo (PLAC), ezetimibe (EZE) to inhibit cholesterol absorption, simvastatin (SIMVA) to reduce cholesterol synthesis and a combination of both (EZE+SIMVA). Results were compared to those obtained in 18 pure vegetarian subjects (vegans) whose dietary Chol intake is extremely low. Relative or fractional Chol absorption (FrChA) was measured with the continuous feeding stable isotope procedure, ChS and BAS with the cholesterol balance method. The daily Chol intake (DICh) was inventoried and the daily Chol absorption (DACh) calculated. Monitoring cholesterol absorption, R_Camp, R_Sit and R_Cholol responded sensitively to changes in FrChA. R_Camp correlated well with FrChA in all omnivore treatment groups and in the vegan group. R_Camp confirmed reduced FrChA under EZE treatment and reduced DACh in the vegan subjects. R_Sit and R_Cholol did not accurately reflect FrChA or DACh in all situations. Monitoring endogenous cholesterol synthesis, R_Lath correlated with ChS in the vegan group, but in none of the omnivore treatment groups. R_Lath confirmed increased ChS under EZE treatment and was reduced under SIMVA treatment, while ChS was not. An increased ChS under EZE+SIMVA treatment could not be confirmed with R_Lath. R_Lath responded very insensitively to a change in ChS. Monitoring BAS, R_7α-OH-Ch but not R_27-OH-Ch correlated with BAS during PLAC, EZE and SIMVA treatments. In line with BAS, R_7α-OH-Ch did not differ in any of the omnivore treatment groups. R_7α-OH-Ch responded insensitively to a change in BAS. Under Chol absorption restriction, serum R_Camp is a sensitive and valid marker to monitor FrChA in a population with a normal DICh. Also, major changes in DACh can be detected in vegans. Serum R_Lath does not reflect ChS measured with the cholesterol balance method during EZE treatment. This result initiates the question whether the measured ChS reflects pure de novo synthesis. Serum R_7α-OH-Ch appears to be a valid but insensitive marker for BAS. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Assessing the Effect of Pretreatments on the Structure and Functionality of Microbial Communities for the Bioconversion of Microalgae to Biogas

    Directory of Open Access Journals (Sweden)

    Olivia Córdova

    2018-06-01

    Full Text Available Microalgae biomethanization is driven by anaerobic sludge associated microorganisms and is generally limited by the incomplete hydrolysis of the microalgae cell wall, which results in a low availability of microalgal biomass for the methanogenic community. The application of enzymatic pretreatments, e.g., with hydrolytic enzymes, is among the strategies used to work around the incomplete hydrolysis of the microalgae cell wall. Despite the proven efficacy of these pretreatments in increasing biomethanization, the changes that a given pretreatment may cause to the anaerobic sludge associated microorganisms during biomethanization are still unknown. This study evaluated the changes in the expression of the metatranscriptome of anaerobic sludge associated microorganisms during Chlorella sorokiniana biomethanization without pretreatment (WP (control and pretreated with commercial cellulase in order to increase the solubilization of the microalgal organic matter. Pretreated microalgal biomass experienced significant increases in biogas the production. The metatranscriptomic analysis of control samples showed functionally active microalgae cells, a bacterial community dominated by γ- and δ-proteobacteria, and a methanogenic community dominated by Methanospirillum hungatei. In contrast, pretreated samples were characterized by the absence of active microalgae cells and a bacteria population dominated by species of the Clostridia class. These differences are also related to the differential activation of metabolic pathways e.g., those associated with the degradation of organic matter during its biomethanization.

  2. One step bioconversion of waste precious metals into Serratia biofilm-immobilized catalyst for Cr(VI) reduction.

    Science.gov (United States)

    Yong, P; Liu, W; Zhang, Z; Beauregard, D; Johns, M L; Macaskie, L E

    2015-11-01

    For reduction of Cr(VI) the Pd-catalyst is excellent but costly. The objectives were to prove the robustness of a Serratia biofilm as a support for biogenic Pd-nanoparticles and to fabricate effective catalyst from precious metal waste. Nanoparticles (NPs) of palladium were immobilized on polyurethane reticulated foam and polypropylene supports via adhesive biofilm of a Serratia sp. The biofilm adhesion and cohesion strength were unaffected by palladization and catalytic biofilm integrity was also shown by magnetic resonance imaging. Biofilm-Pd and mixed precious metals on biofilm (biofilm-PM) reduced 5 mM Cr(VI) to Cr(III) when immobilized in a flow-through column reactor, at respective flow rates of 9 and 6 ml/h. The lower activity of the latter was attributed to fewer, larger, metal deposits on the bacteria. Activity was lost in each case at pH 7 but was restored by washing with 5 mM citrate solution or by exposure of columns to solution at pH 2, suggesting fouling by Cr(III) hydroxide product at neutral pH. A 'one pot' conversion of precious metal waste into new catalyst for waste decontamination was shown in a continuous flow system based on the use of Serratia biofilm to manufacture and support catalytic Pd-nanoparticles.

  3. Bioconversion of agro-industrial by-products in rhamnolipids toward applications in enhanced oil recovery and bioremediation.

    Science.gov (United States)

    Gudiña, Eduardo J; Rodrigues, Ana I; Alves, Eliana; Domingues, M Rosário; Teixeira, José A; Rodrigues, Lígia R

    2015-02-01

    In this work, biosurfactant production by a Pseudomonas aeruginosa strain was optimized using low-cost substrates. The highest biosurfactant production (3.2 g/l) was obtained using a culture medium containing corn steep liquor (10% (v/v)) and molasses (10% (w/v)). The biosurfactant reduced the surface tension of water up to 30 mN/m, and exhibited a high emulsifying activity (E24=60%), with a critical micelle concentration as low as 50 mg/l. The biosurfactant produced in this alternative medium was characterized as a mixture of eight different rhamnolipid congeners, being the most abundant the mono-rhamnolipid Rha-C10-C10. However, using LB medium, nine different rhamnolipid congeners were identified, being the most abundant the di-rhamnolipid Rha-Rha-C10-C10. The rhamnolipid mixture produced in the alternative medium exhibited a better performance in removing oil from contaminated sand when compared with two chemical surfactants, suggesting its potential use as an alternative to traditional chemical surfactants in enhanced oil recovery or bioremediation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Screening of lactic acid bacteria for their potential as microbial cell factories for bioconversion of lignocellulosic feedstocks

    DEFF Research Database (Denmark)

    Boguta, Anna Monika; Bringel, Francoise; Martinussen, Jan

    2014-01-01

    Background: The use of fossil carbon sources for fuels and petrochemicals has serious impacts on our environment and is unable to meet the demand in the future. A promising and sustainable alternative is to substitute fossil carbon sources with microbial cell factories converting lignocellulosic ...

  5. Construction and Optimization of a Heterologous Pathway for Protocatechuate Catabolism in Escherichia coli Enables Bioconversion of Model Aromatic Compounds

    Energy Technology Data Exchange (ETDEWEB)

    Clarkson, Sonya M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Biosciences Division; Giannone, Richard J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Chemical Sciences Division; Kridelbaugh, Donna M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Biosciences Division; Elkins, James G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Biosciences Division; Guss, Adam M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Biosciences Division; Michener, Joshua K. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Biosciences Division, BioEnergy Science Center; Vieille, Claire [Michigan State Univ., East Lansing, MI (United States)

    2017-07-21

    The production of biofuels from lignocellulose yields a substantial lignin by-product stream that currently has few applications. Biological conversion of lignin-derived compounds into chemicals and fuels has the potential to improve the economics of lignocellulose-derived biofuels, but few microbes are able both to catabolize lignin-derived aromatic compounds and to generate valuable products. WhileEscherichia colihas been engineered to produce a variety of fuels and chemicals, it is incapable of catabolizing most aromatic compounds. Therefore, we engineeredE. colito catabolize protocatechuate, a common intermediate in lignin degradation, as the sole source of carbon and energy via heterologous expression of a nine-gene pathway fromPseudomonas putidaKT2440. Then, we used experimental evolution to select for mutations that increased growth with protocatechuate more than 2-fold. Increasing the strength of a single ribosome binding site in the heterologous pathway was sufficient to recapitulate the increased growth. After optimization of the core pathway, we extended the pathway to enable catabolism of a second model compound, 4-hydroxybenzoate. These engineered strains will be useful platforms to discover, characterize, and optimize pathways for conversions of lignin-derived aromatics.

    IMPORTANCELignin is a challenging substrate for microbial catabolism due to its polymeric and heterogeneous chemical structure. Therefore, engineering microbes for improved catabolism of lignin-derived aromatic compounds will require the assembly of an entire network of catabolic reactions, including pathways from genetically intractable strains. By constructing defined pathways for aromatic compound degradation in a model host would allow rapid identification, characterization, and optimization of novel pathways. Finally, we constructed and optimized one such pathway inE. colito enable catabolism of a model aromatic compound, protocatechuate, and then extended the pathway to a related compound, 4-hydroxybenzoate. This optimized strain can now be used as the basis for the characterization of novel pathways.

  6. The Large Scale Identification and Quantification of Conjugates of Intact and Gut Microbial Bioconversion Products of Polyphenols.

    NARCIS (Netherlands)

    Hooft, van der J.J.J.; Vos, de C.H.; Bino, R.J.; Mihaleva, V.V.; Ridder, L.O.; Roo, de N.; Jacobs, D.M.; Duynhoven, van J.P.M.; Vervoort, J.

    2013-01-01

    A human diet containing a significant amount of flavonoids, such as present in tea, red wine, apple, and cocoa has been associated with reduced disease risks. After consumption, a part of these flavonoids can be directly absorbed by the small intestine, but the greatest part passages towards the

  7. Increased availability of NADH in metabolically engineered baker's yeast improves transaminase-oxidoreductase coupled asymmetric whole-cell bioconversion

    DEFF Research Database (Denmark)

    Knudsen, Jenny Dahl; Hägglöf, Cecilia; Weber, Nora

    2016-01-01

    yeast for transamination-reduction coupled asymmetric one-pot conversion was investigated. RESULTS: A series of active whole-cell biocatalysts were constructed by over-expressing the (S)-selective ω-transaminase (VAMT) from Capsicum chinense together with the NADH-dependent (S)-selective alcohol...

  8. Bioconversion of Agricultural By-Products to Lysin by brevibacterium flavum and physico-chemical optimization for hyper-production

    International Nuclear Information System (INIS)

    Irshad, S.; Hashmi, A. S.; Babar, M. E.; Awan, A. R.; Anjum, A. A.; Javed, M. M.

    2015-01-01

    Poultry and agriculture industry has a great role in the development of food sector in Pakistan. Whole of the Lysine required for poultry feed is imported to fulfil the desired dietary needs. Present study was designed to utilize different agricultural by-products like molasses, wheat bran, rice polishing and corn steep liquor. Different Physico-Chemical parameters were optimized to have hyper-production of Lysine through fermentation by using Brevibacterium flavum as a fermentative agent. From wheat bran, rice polishing and molasses (as best carbon source), significantly high concentrations of lysine (10.4 g/L) after 72h of incubation was observed with molasses (4 percentage) with 3 percentage (v/v) inoculum size at 30 degree C and pH 7. Among different nitrogen sources, 0.25 percentage (NH/sub 4/)2SO/sub 4/ showed significantly (P< 0.05) high yield of Lysine (16.89 g/L). Addition of different optimum levels of ionic salts; 4 percentage CaCO/sub 3/, 0.4 percentage MgSO/sub 4/.7H/sub 2/O, 0.1 percentage NaCl and 0.2 percentage KH/sub 2/PO/sub 4/ gave significantly (P< 0.05) higher quantity of Lysine 19.01 g/L. Inclusion of 0.6 percentage corn steep liquor and 0.4 mg/100mL biotin significantly (P< 0.05) raised the Lysine from 19.4 g/L - 19.45 g/L. The presence of Lysine in fermented broth was detected by TLC. Thus a cheap and practical bioprocess of Lysine production was concluded, that can be exploited commercially to save foreign exchange. (author)

  9. Bioconversion of deoxypodophyllotoxin into epipodophyllotoxin in E-coli using human cytochrome P450 3A4

    NARCIS (Netherlands)

    Vasilev, Nikolay P.; Julsing, Mattijs K.; Koulman, Albert; Clarkson, Cailean; Woerdenbag, Herman J.; Ionkova, Iliana; Bos, Rein; Jaroszewski, Jerzy W.; Kayser, Oliver; Quax, Wim J.

    2006-01-01

    Biotransformation of deoxypodophyllotoxin to epipodophyllotoxin by three major human hepatic enzymes, CYP1A2, CYP2C9 and CYP3A4, heterologously expressed in E coli DH5 alpha, was investigated. It was shown that CYP3A4 catalysed the hydroxylation of deoxypodophyllotoxin into epipodophyllotoxin in

  10. Bioconversion of Beetle-Killed Lodgepole Pine Using SPORL: Process Scale-up Design, Lignin Coproduct, and High Solids Fermentation without detoxification

    Science.gov (United States)

    Haifeng Zhou; J.Y. Zhu; Xiaolin Luo; Shao-Yuan Leu; Xiaolei Wu; Roland Gleisner; Bruce S. Dien; Ronald E. Hector; Dongjie Yang; Xueqing Qiu; Eric Horn; Jose Negron

    2013-01-01

    Mountain pine beetle killed Lodgepole pine (Pinus contorta Douglas ex Loudon) wood chips were pretreated using an acidic sulfite solution of approximately pH = 2.0 at a liquor to wood ratio of 3 and sodium bisulfite loading of 8 wt % on wood. The combined hydrolysis factor (CHF), formulated from reaction kinetics, was used to design a scale-up...

  11. Anaerobic digestion of goat manure: bio-conversion of energy and bio fertilizer; Digestao anaerobica de dejetos de caprinos: conversor biologico de energia e biofertilizante

    Energy Technology Data Exchange (ETDEWEB)

    Canafistula, Francisco Jose Firmino; Carvalho, Paulo Cesar Marques de; Teixeira, Adunias dos Santos [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Dept. Engenharia Eletrica], Emails: firmino@ufc.br, carvalho@dee.ufc.br, adunias@ufc.com

    2009-07-01

    This research aims at analyzing biogas produced by anaerobic digestion of goat excrements related to energy generation, in addition to analyzing the bio-fertilizer as a byproduct of the process. Therefore, new products are generated from semi-intensive and extensive of goats, increasing its economical and environmental viability of the activity. The biogas was applied as the fuel for an Otto cycle internal combustion engine of 5.5 HP used to drive a hydraulic pump that supplied water to an area of one hectare of pasture. In addition, the spreadsheet GDER was applied to compute the kWh cost of the following electricity sources: biogas from goat excrement, diesel, electrical grid, wind and solar. It was found tat the biogas can substitute 30% of the daily energy requirements, and one can state that 1 m{sup 3} of biogas is equivalent to 740 mL of gasoline. (author)

  12. Anaerobic bioconversion of organic waste into biogas by hot water treatment at near-critical conditions: application in bioregenerative life support.

    Science.gov (United States)

    Lissens, Geert; Verstraete, Willy; Albrecht, Tobias; Brunner, Gerd; Lasseur, Christophe

    2003-01-01

    The feasibility of nearly-complete conversion of lignocellulosic waste (70% food crops, 20% faecal matter and 10% green algae) into biogas was investigated in the context of a Life Support Project. The treatment comprised a series of processes, i.e. a mesophilic laboratory scale CSTR (continuously stirred tank reactor), an upflow biofilm reactor and a hydrothermolysis system in near-critical water. By the one-stage CSTR, a biogas yield of 75% with a specific biogas production of 0.37 l biogas g(-1) VSS (volatile suspended solids) added at a HRT (hydraulic retention time) of 20 d was obtained. Biogas yields further increased with 10-15% at HRT > 20 d, indicating the hydrolysis of lignocellulose to be the rate-limiting conversion step. The solids present in the CSTR-effluent were subsequently treated by hot water treatment (T approximately 310-350 degrees C, p approximately 240 bar), resulting in effective carbon liquefaction (50-60% without and 83% with carbon dioxide saturation) and complete hygienisation of the residue. Subsequent anaerobic digestion of the hydrolysate allowed further conversion of 48-60% on COD (chemical oxygen demand) basis. Thus, the total process yielded biogas corresponding with a COD conversion up to 90% of the original organic matter. It appears that mesophilic digestion in conjunction with hydrothermolysis at near-critical conditions offers interesting features for (nearly) complete, non-toxic and hygienic carbon and energy recovery from human waste in a bioregenerative life support context.

  13. Cloning, expression and characterization of L-arabinose isomerase from Thermotoga neapolitana: bioconversion of D-galactose to D-tagatose using the enzyme.

    Science.gov (United States)

    Kim, Byoung-Chan; Lee, Yoon-Hee; Lee, Han-Seung; Lee, Dong-Woo; Choe, Eun-Ah; Pyun, Yu-Ryang

    2002-06-18

    Gene araA encoding an L-arabinose isomerase (AraA) from the hyperthermophile, Thermotoga neapolitana 5068 was cloned, sequenced, and expressed in Escherichia coli. The gene encoded a polypeptide of 496 residues with a calculated molecular mass of 56677 Da. The deduced amino acid sequence has 94.8% identical amino acids compared with the residues in a putative L-arabinose isomerase of Thermotoga maritima. The recombinant enzyme expressed in E. coli was purified to homogeneity by heat treatment, ion exchange chromatography and gel filtration. The thermophilic enzyme had a maximum activity of L-arabinose isomerization and D-galactose isomerization at 85 degrees C, and required divalent cations such as Co(2+) and Mn(2+) for its activity and thermostability. The apparent K(m) values of the enzyme for L-arabinose and D-galactose were 116 mM (v(max), 119 micromol min(-1) mg(-1)) and 250 mM (v(max), 14.3 micromol min(-1) mg(-1)), respectively, that were determined in the presence of both 1 mM Co(2+) and 1 mM Mn(2+). A 68% conversion of D-galactose to D-tagatose was obtained using the recombinant enzyme at the isomerization temperature of 80 degrees C.

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

    Science.gov (United States)

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

    2014-10-15

    Nine agro-industrial and forestry by-products were subjected to solid-state fermentation by Agrocybe cylindracea and Pleurotus ostreatus, and the process and end-products were comparatively evaluated. Grape marc waste plus cotton gin trash was the best performing medium for both fungi, while substrate composition had a marked effect on most cultivation parameters. Biological efficiency was positively correlated with nitrogen, lignin and ash, and negatively with hemicelluloses and carbohydrate content of substrates. Spent substrates demonstrated high reductions in hemicelluloses and cellulose in contrast to lignin; fibre fractions were correlated with nitrogen, fat and ash content of initial materials, while residual mycelial biomass was affected by mushroom productivity. Mushroom proximate analysis revealed significant variations of constituents depending on the substrate. Crude protein and fat were correlated with substrates nitrogen for both species. Alternative cultivation substrates of high potential are proposed, while spent material could be exploited as animal feed due to its upgraded properties. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Effect of bioconversion conditions on vanillin production by Amycolatopsis sp. ATCC 39116 through an analysis of competing by-product formation.

    Science.gov (United States)

    Ma, Xiao-kui; Daugulis, Andrew J

    2014-05-01

    This study investigated the effects of transformation conditions such as initial pH, the initial concentration of glucose and yeast extract in the medium, and the separate addition of ferulic acid and vanillic acid, on the production of vanillin through an analysis of competing by-product formation by Amycolatopsis sp. ATCC 39116. The extent and nature of by-product formation and vanillin yield were affected by initial pH and different initial concentrations of glucose and yeast extract in the medium, with a high yield of vanillin and high cell density obtained at pH 8.0, 10 g/l glucose, and 8 g/l yeast extract. High concentrations of ferulic acid were found to negatively affect cell density. Additional supplementation of 100 mg/l vanillic acid, a metabolically linked by-product, was found to result in a high concentration of vanillin and guaiacol, an intermediate of vanillin. Via an analysis of the effect of these transformation conditions on competing by-product formation, high concentrations of ferulic acid were transformed with a molar yield to vanillin of 96.1 and 95.2 %, by Amycolatopsis sp. ATCC 39116 and Streptomyces V1, respectively, together with a minor accumulation of by-products. These are among the highest performance values reported in the literature to date for Streptomyces in batch cultures.

  16. Bioconversion of beetle-killed lodgepole pine using SPORL: Process scale-up design, lignin co-product, and high solids fermentation without detoxification

    Science.gov (United States)

    Mountain pine beetle killed Lodgepole pine (Pinus contorta Douglas ex Loudon) wood chips were pretreated using an acidic sulfite solution of approximately pH = 2.0 at a liquor to wood ratio of 3 and sodium bisulfite loading of 8 wt % on wood. The combined hydrolysis factor (CHF), formulated from rea...

  17. Liberation of fermentable sugars from soybean hull biomass using ionic liquid 1-butyl-3-methylimidazolium acetate and their bioconversion to ethanol.

    Science.gov (United States)

    da Cunha-Pereira, Fernanda; Rech, Rosane; Záchia Ayub, Marco Antônio; Pinheiro Dillon, Aldo; Dupont, Jairton

    2016-03-01

    Optimized hydrolysis of lignocellulosic waste biomass is essential to achieve the liberation of sugars to be used in fermentation process. Ionic liquids (ILs), a new class of solvents, have been tested in the pretreatment of cellulosic materials to improve the subsequent enzymatic hydrolysis of the biomass. Optimized application of ILs on biomass is important to advance the use of this technology. In this research, we investigated the effects of using 1-butyl-3-methylimidazolium acetate ([bmim][Ac]) on the decomposition of soybean hull, an abundant cellulosic industrial waste. Reaction aspects of temperature, incubation time, IL concentration, and solid load were optimized before carrying out the enzymatic hydrolysis of this residue to liberate fermentable glucose. Optimal conditions were found to be 75°C, 165 min incubation time, 57% (mass fraction) of [bmim][Ac], and 12.5% solid loading. Pretreated soybean hull lost its crystallinity, which eased enzymatic hydrolysis, confirmed by Fourier Transform Infrared analysis. The enzymatic hydrolysis of the biomass using an enzyme complex from Penicillium echinulatum liberated 92% of glucose from the cellulose matrix. The hydrolysate was free of any toxic compounds, such as hydroxymethylfurfural and furfural. The obtained hydrolysate was tested for fermentation using Candida shehatae HM 52.2, which was able to convert glucose to ethanol at yields of 0.31. These results suggest the possible use of ILs for the pretreatment of some lignocellulosic waste materials, avoiding the formation of toxic compounds, to be used in second-generation ethanol production and other fermentation processes. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 32:312-320, 2016. © 2015 American Institute of Chemical Engineers.

  18. MATHEMATICAL MODELING, AUTOMATION AND CONTROL OF THE BIOCONVERSION OF SORBITOL TO SORBOSE IN THE VITAMIN C PRODUCTION PROCESS I. MATHEMATICAL MODELING

    Directory of Open Access Journals (Sweden)

    A. Bonomi

    1997-12-01

    Full Text Available In 1990, the Biotechnology and the Control Systems Groups of IPT started developing a system for the control and automation of fermentation processes, applied to the oxidation of sorbitol to sorbose by the bacteria Gluconobacter oxydans, the microbial step of the vitamin C production process, that was chosen as a case study. Initially, a thirteen-parameter model was fitted to represent the batch operation of the system utilizing a nonlinear regression analysis, the flexible polyhedron method. Based on these results, a model for the continuous process (with the same kinetic equations was constructed and its optimum operating point obtained

  19. Bioconversion of mixed free fatty acids to poly-3-hydroxyalkanoates by Pseudomonas putida BET001 and modeling of its fermentation in shake flasks

    Directory of Open Access Journals (Sweden)

    Khalil Munawar Makhdum Munawar

    2016-01-01

    Conclusion: The findings of this study provided add to the literature on key variables in for achieving good microbial growth and mcl-PHA production in shake flasks culture. In addition, suitable kinetic model to describe cultivation in this system was also presented.

  20. Bioconversion of paper sludge to biofuel by simultaneous saccharification and fermentation using a cellulase of paper sludge origin and thermotolerant Saccharomyces cerevisiae TJ14

    Directory of Open Access Journals (Sweden)

    Harashima Satoshi

    2011-09-01

    Full Text Available Abstract Background Ethanol production from paper sludge (PS by simultaneous saccharification and fermentation (SSF is considered to be the most appropriate way to process PS, as it contains negligible lignin. In this study, SSF was conducted using a cellulase produced from PS by the hypercellulase producer, Acremonium cellulolyticus C-1 for PS saccharification, and a thermotolerant ethanol producer Saccharomyces cerevisiae TJ14 for ethanol production. Using cellulase of PS origin minimizes biofuel production costs, because the culture broth containing cellulase can be used directly. Results When 50 g PS organic material (PSOM/l was used in SSF, the ethanol yield based on PSOM was 23% (g ethanol/g PSOM and was two times higher than that obtained by a separate hydrolysis and fermentation process. Cellulase activity throughout SSF remained at around 60% of the initial activity. When 50 to 150 g PSOM/l was used in SSF, the ethanol yield was 21% to 23% (g ethanol/g PSOM at the 500 ml Erlenmeyer flask scale. Ethanol production and theoretical ethanol yield based on initial hexose was 40 g/l and 66.3% (g ethanol/g hexose at 80 h, respectively, when 161 g/l of PSOM, 15 filter paper units (FPU/g PSOM, and 20% inoculum were used for SSF, which was confirmed in the 2 l scale experiment. This indicates that PS is a good raw material for bioethanol production. Conclusions Ethanol concentration increased with increasing PSOM concentration. The ethanol yield was stable at PSOM concentrations of up to 150 g/l, but decreased at concentrations higher than 150 g/l because of mass transfer limitations. Based on a 2 l scale experiment, when 1,000 kg PS was used, 3,182 kFPU cellulase was produced from 134.7 kg PS. Produced cellulase was used for SSF with 865.3 kg PS and ethanol production was estimated to be 51.1 kg. Increasing the yeast inoculum or cellulase concentration did not significantly improve the ethanol yield or concentration.

  1. Interaction of Microbial and Abiotic Processes in Soil Leading to the (Bio)Conversion and Ultimate Attenuation of New Insensitive Munitions Compounds

    Science.gov (United States)

    2016-12-30

    adenine dinucleotide (phosphate) NC Camp Butner soil (alternative abbreviation, soil is from North Carolina) NCBI National Center for Biotechnology ...knowledge and perspectives of bioelimination of xenobiotic compounds. Journal of Biotechnology 51, 287-295, doi:http://dx.doi.org/10.1016/S0168...McKenzie, R. M. The synthesis of birnessite, cryptomelane, and some other oxides and hydroxides of manganese. Mineralogical Magazine 38, 493-502

  2. Bioconversion of l-glutamic acid to α-ketoglutaric acid by an immobilized whole-cell biocatalyst expressing l-amino acid deaminase from Proteus mirabilis.

    Science.gov (United States)

    Hossain, Gazi Sakir; Li, Jianghua; Shin, Hyun-dong; Chen, Rachel R; Du, Guocheng; Liu, Long; Chen, Jian

    2014-01-01

    The goal of this work was to develop an immobilized whole-cell biocatalytic process for the environment-friendly synthesis of α-ketoglutaric acid (α-KG) from l-glutamic acid. We compared the suitability of Escherichia coli and Bacillus subtilis strains overexpressing Proteus mirabilisl-amino acid deaminase (l-AAD) as potential biocatalysts. Although both recombinant strains were biocatalytically active, the performance of B. subtilis was superior to that of E. coli. With l-glutamic acid as the substrate, α-KG production levels by membranes isolated from B. subtilis and E. coli were 55.3±1.73 and 21.7±0.39μg/mg protein/min, respectively. The maximal conversion ratio of l-glutamic acid to α-KG was 31% (w/w) under the following optimal conditions: 15g/L l-glutamic acid, 20g/L whole-cell biocatalyst, 5mM MgCl2, 40°C, pH 8.0, and 24-h incubation. Immobilization of whole cells with alginate increased the recyclability by an average of 23.33% per cycle. This work established an efficient one-step biotransformation process for the production of α-KG using immobilized whole B. subtilis overexpressing P. mirabilisl-AAD. Compared with traditional multistep chemical synthesis, the biocatalytic process described here has the advantage of reducing environmental pollution and thus has great potential for the large-scale production of α-KG. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Evaluation of the antioxidant properties of N-acetylcysteine in human platelets: prerequisite for bioconversion to glutathione for antioxidant and antiplatelet activity.

    Science.gov (United States)

    Gibson, Kyle R; Neilson, Ilene L; Barrett, Fiona; Winterburn, Tim J; Sharma, Sushma; MacRury, Sandra M; Megson, Ian L

    2009-10-01

    N-Acetylcysteine (NAC) is a frequently used "antioxidant" in vitro, but the concentrations applied rarely correlate with those encountered with oral dosing in vivo. Here, we investigated the in vitro antioxidant and antiplatelet properties of NAC at concentrations (10-100 microM) that are achievable in plasma with tolerable oral dosing. The impact of NAC pretreatment (2 hours) on aggregation of platelets from healthy volunteers in response to thrombin and adenosine diphosphate and on platelet-derived nitric oxide (NO) was examined. NAC was found to be a weak reducing agent and a poor antioxidant compared with glutathione (reduced form) (GSH). However, platelets treated with NAC showed enhanced antioxidant activity and depression of reactive oxygen species generation associated with increases in intraplatelet GSH levels. An approximately 2-fold increase in NO synthase-derived nitrite was observed with 10 microM NAC treatment, but the effect was not concentration dependent. Finally, NAC significantly reduced both thrombin-induced and adenosine diphosphate-induced platelet aggregation. NAC should be considered a weak antioxidant that requires prior conversion to GSH to convey antioxidant and antithrombotic benefit at therapeutically relevant concentrations. Our results suggest that NAC might be an effective antiplatelet agent in conditions where increased oxidative stress contributes to heightened risk of thrombosis but only if the intraplatelet machinery to convert it to GSH is functional.

  4. Bioconversion of α-[14C]Zearalenol and β-[14C]Zearalenol into [14C]Zearalenone by Fusarium roseum Gibbosum

    International Nuclear Information System (INIS)

    Richardson, K.E.; Hagler, W.M. Jr.; Hamilton, P.B.

    1984-01-01

    Cultures of Fusarium roseum Gibbosum on rice were treated with [ 14 C]zearalenone, α-[ 14 C]zearalenol, or β-[ 14 C]zearalenol to determine whether a precursor-product relationship exists among these closely related fungal metabolites. Culture extracts were purified by silica gel column chromatography and fractionated by high-pressure liquid chromatography, and the level of radioactivity was determined. Within 7 days, the β-[ 14 C]zearalenol was converted to zearalenone, and no residual β-[ 14 C]zearalenol was detectable. Most of the α-[ 14 C]zearalenol added was also converted into zearalenone within 14 days. In cultures treated with [ 14 C]zearalenone, no radioactivity was noted in any other components

  5. Study on potency of municipal solid waste conversion into renewable energy by thermal incineration and bioconversion: case study of Medan city

    Science.gov (United States)

    Sarah, Maya; Misran, Erni

    2018-03-01

    Municipal solid waste (MSW) in Medan City is facing problems either with the quantity and management of MSW. Local authority only dumped approximately 73.9% MSW in the landfill over the years. Spontaneous phenomena of methane formation in dumping site indicates the potency of MSW conversion into energy by biochemical conversion. On the contrary, the presence of plastics, woods, papers, etc. in the MSW show the potency of MSW to be treated by thermal conversion. Both thermal incineration and anaerobic digestion may convert MSW Medan City into energy. This study evaluates potency of MSW conversion into renewable energy using proximate and ultimate analysis. Overall, MSW of Medan City has the opportunities to be converted into energy by both thermal and biochemical conversion with a special requirement such as pre-dry the MSW prior incineration process and degrade organic MSW in a bioreactor.

  6. Report: Bioconversion of agriculture waste to lysine with UV mutated strain of brevibacterium flavum and its biological evaluation in broiler chicks.

    Science.gov (United States)

    Tabassum, Alia; Hashmi, Abu Saeed; Masood, Faiza; Iqbal, Muhammad Aamir; Tayyab, Muhammad; Nawab, Amber; Nadeem, Asif; Sadeghi, Zahra; Mahmood, Adeel

    2015-07-01

    Lysine executes imperative structural and functional roles in body and its supplementation in diet beneficial to prevent the escalating threat of protein deficiency. The physical mutagenesis offers new fascinating avenues of research for overproduction of lysine through surplus carbohydrate containing agriculture waste especially in developing countries. The current study was aimed to investigate the potential of UV mutated strain of Brevibacterium flavum at 254 nm for lysine production. The physical and nutritional parameters were optimized and maximum lysine production was observed with molasses (4% substrate water ratio). Moreover, supplementation of culture medium with metal cations (i.e. 0.4% CaSO₄, 0.3% NaCl, 0.3% KH₂PO₄, 0.4% MgSO₄, and 0.2% (NH₄) ₂SO₄w/v) together with 0.75% v/v corn steep liquor significantly enhanced the lysine production up to 26.71 ± 0.31 g/L. Though, concentrations of urea, ammonium nitrate and yeast sludge did not exhibit any profound effect on lysine production. Biological evaluation of lysine enriched biomass in terms of weight gain and feed conversion ratio reflected non-significant difference for experimental and control (+ve) groups. Conclusively, lysine produced in the form of biomass was compatible to market lysine in its effectiveness and have potential to utilize at commercial scale.

  7. Enhancing the Bioconversion of Winery and Olive Mill Waste Mixtures into Lignocellulolytic Enzymes and Animal Feed by Aspergillus uvarum Using a Packed-Bed Bioreactor.

    Science.gov (United States)

    Salgado, José Manuel; Abrunhosa, Luís; Venâncio, Armando; Domínguez, José Manuel; Belo, Isabel

    2015-10-28

    Wineries and olive oil industries are dominant agro-industrial activities in southern European regions. Olive pomace, exhausted grape marc, and vine shoot trimmings are lignocellulosic residues generated by these industries, which could be valued biotechnologically. In the present work these residues were used as substrate to produce cellulases and xylanases through solid-state fermentation using Aspergillus uvarum MUM 08.01. For that, two factorial designs (3(2)) were first planned to optimize substrate composition, temperature, and initial moisture level. Subsequently, the kinectics of cellulolytic enzyme production, fungal growth, and fermented solid were characterized. Finally, the process was performed in a packed-bed bioreactor. The results showed that cellulase activity improved with the optimization processes, reaching 33.56 U/g, and with the packed-bed bioreactor aeration of 0.2 L/min, reaching 38.51 U/g. The composition of fermented solids indicated their potential use for animal feed because cellulose, hemicellulose, lignin, and phenolic compounds were partially degraded 28.08, 10.78, 13.3, and 28.32%, respectively, crude protein was increased from 8.47 to 17.08%, and the mineral contents meet the requirements of main livestock.

  8. Detoxification of Olive Mill Wastewater and Bioconversion of Olive Crop Residues into High-Value-Added Biomass by the Choice Edible Mushroom Hericium erinaceus.

    Science.gov (United States)

    Koutrotsios, Georgios; Larou, Evangelia; Mountzouris, Konstantinos C; Zervakis, Georgios I

    2016-09-01

    Environmentally acceptable disposal of olive cultivation residues (e.g., olive prunings; olive pruning residues (OLPR)) and olive mill wastes is of paramount importance since they are generated in huge quantities within a short time. Moreover, olive mill wastewater (OMW) or sludge-like effluents ("alperujo"; two-phase olive mill waste (TPOMW)) are highly biotoxic. Hericium erinaceus is a white-rot fungus which produces choice edible mushrooms on substrates rich in lignocellulosics, and its suitability for the treatment of olive by-products was examined for the first time. Fungal growth resulted in a notable reduction of OMW's pollution parameters (i.e., 65 % decolorization, 47 % total phenolic reduction, and 52 % phytotoxicity decrease) and correlated with laccase and manganese peroxidase activities. Solid-state fermentation of various mixtures of OLPR, TPOMW, and beech sawdust (control) by H. erinaceus qualified OLPR in subsequent cultivation experiments, where it exhibited high mushroom yields and biological efficiency (31 %). Analyses of proximate composition and bioactive compound content revealed that mushrooms deriving from OLPR substrates showed significantly higher crude fat, total glucan, β-glucan, total phenolics, and ferric-reducing antioxidant potential values than the control. H. erinaceus demonstrated the potential to detoxify OMW and bioconvert OLPR into high-quality biomass, and hence, this fungus could be successfully exploited for the treatment of such by-products.

  9. Bioconversion of Coal: Hydrologic indicators of the extent of coal biodegradation under different redox conditions and coal maturity, Velenje Basin case study, Slovenia

    Science.gov (United States)

    Kanduč, Tjaša; Grassa, Fausto; Lazar, Jerneja; Jamnikar, Sergej; Zavšek, Simon; McIntosh, Jennifer

    2014-05-01

    Underground mining of coal and coal combustion for energy has significant environmental impacts. In order to reduce greenhouse gas emissions, other lower -carbon energy sources must be utilized. Coalbed methane (CBM) is an important source of relatively low-carbon energy. Approximately 20% of world's coalbed methane is microbial in origin (Bates et al., 2011). Interest in microbial CBM has increased recently due to the possibility of stimulating methanogenesis. Despite increasing interest, the hydrogeochemical conditions and mechanisms for biodegradation of coal and microbial methane production are poorly understood. This project aims to examine geochemical characteristics of coalbed groundwater and coalbed gases in order to constrain biogeochemical processes to better understand the entire process of coal biodegradation of coal to coalbed gases. A better understanding of geochemical processes in CBM areas may potentially lead to sustainable stimulation of microbial methanogenesis at economical rates. Natural analogue studies of carbon dioxide occurring in the subsurface have the potential to yield insights into mechanisms of carbon dioxide storage over geological time scales (Li et al., 2013). In order to explore redox processes related to methanogenesis and determine ideal conditions under which microbial degradation of coal is likely to occur, this study utilizes groundwater and coalbed gas samples from Velenje Basin. Determination of the concentrations of methane, carbondioxide, nitrogen, oxygen, argon was performed with homemade NIER mass spectrometer. Isotopic composition of carbon dioxide, isotopic composition of methane, isotopic composition of deuterium in methane was determined with Europa-Scientific IRMS with an ANCA-TG preparation module and Thermo Delta XP GC-TC/CF-IRMS coupled to a TRACE GC analyzer. Total alkalinity of groundwater was measured by Gran titration. Major cations were analyzed by ICP-OES and anions by IC method. Isotopic composition of dissolved inorganic carbon was determined by MultiflowBio preparation module. The stable isotope composition of sulphur was determined with a Europa Scientific 20-20 continuous flow IRMS ANCA-SL preparation module. Concentrations of tritium were determined with the electrolytic enrichment method. PHREEQC for Windows was used to perform thermodynamic modelling. The average coalbed gas composition in the coalbed seam is approximately carbon dioxide: methane > 2:1, where a high proportion of CO2 is adsorbed on the lignite structure, while methane is present free in coal fractures. It can be concluded that isotopic composition of carbon in methane from -70.4‰ to -50.0‰ is generated via acetate fermentation and via reduction of carbon dioxide, while isotopic composition of carbon in methane values range from -50.0‰ to -18.8‰, thermogenic methane can be explained by secondary processes, causing enrichment of residual methane with the heavier carbon isotope. Isotopic composition of deuterium in methane range from -343.9‰ to -223.1‰. Isotopic composition of carbon in carbon dioxide values at excavation fields range from -11.0‰ to +5‰ and are endogenic and microbial in origin. The major ion chemistry, redox conditions, stable isotopes and tritium measured in groundwater from the Velenje Basin, suggest that the Pliocene and Triassic aquifers contain distinct water bodies. Groundwater in the Triassic aquifer is dominated by hydrogen carbonate, calcium, magnesium and isotopic composition of dissolved inorganic carbon indicating degradation of soil organic matter and dissolution of carbonate minerals, similar to surface waters. In addition, groundwater in the Triassic aquifer has isotopic composition of oxygen and isotopic composition of deuterium values which plot near surface waters on the local and global meteoric water lines and detectable tritium reflects recent recharge. In contrast, groundwater in the Pliocene aquifers is enriched in magnesium, sodium, calcium, potassium, and silica and has alkalinity and isotopic composition of dissolved inorganic carbon values with low sulphate and nitrate concentrations. These waters have likely been influenced by sulfate reduction and microbial methanogenesis associated with coal seams and dissolution of feldspars and magnesium-rich clay minerals. Pliocene aquifer waters are also depleted in heavier oxygen isotope and heavier deuterium isotope and have tritium concentrations near the detection limit, suggesting these waters are older. References Bates, B.L., McIntosh J.C., Lohse K.A., Brooks P.D. 2011: Influence of groundwater flowpaths, residence times, and nutrients on the extent of microbial methanogenesis in coal beds: Powder River Basin, USA, Chemical geology, 284, 45-61. Li, W., Cheng Y., Wang L., Zhou H., Wang H., Wang L. 2013: Evaluating the security of geological coalbed sequestration of supercritical CO2 reservoirs: The Haishiwan coalfield, China as a natural analogue, International Journal of Greenhouse Gas Control, 13, 102-111.

  10. Using sulfite chemistry for robust bioconversion of Douglas-fir forest residue to bioethanol at high titer and lignosulfonate: A pilot-scale evaluation

    Science.gov (United States)

    J.Y. Zhu; M. Subhosh Chandra; Feng Gu; Roland Gleisner; J.Y. Zhu; John Sessions; Gevan Marrs; Johnway Gao; Dwight Anderson

    2015-01-01

    This study demonstrated at the pilot-scale (50 kg) use of Douglas-fir forest harvest residue, an underutilized forest biomass, for the production of high titer and high yield bioethanol using sulfite chemistry without solid–liquor separation and detoxification. Sulfite Pretreatment to Overcome the Recalcitrance of Lignocelluloses (SPORL) was directly applied to the...

  11. DESARROLLO DE ALTERNATIVAS PROTEICAS PARA LA ACUICULTURA CHILENA: MEJORAMIENTO DEL PERFIL NUTRICIONAL DE MATERIAS PRIMAS VEGETALES A TRAVES DE PROCESOS DE BIO-CONVERSION

    OpenAIRE

    BORQUEZ RAMIREZ, ALIRO SAMUEL

    2012-01-01

    El suministro mundial de harina de pescado se ha hecho insuficiente para mantener los sistemas de producción acuícola que se basan en el uso de grandes cantidades de alimento externo. En respuesta a las preocupaciones de sustentabilidad relacionadas con la excesiva dependencia de la harina de pescado, importantes esfuerzos se han centrado en reducir o eliminar este componente de las dietas para organismos acuáticos. En este sentido, es imprescindible evaluar la viabilidad de nueva...

  12. Optimization of diterpenes bioconversion process by the fungus Cephalosporium aphidicola Otimização do processo de bioconversão de compostos diterpênicos pelo fungo Cephalosporium aphidicola

    Directory of Open Access Journals (Sweden)

    Jacqueline Aparecida Takahashi

    2000-06-01

    Full Text Available Parameters for a more efficient biotransformation of diterpene-like compounds by the fungus Cephalosporium aphidicola were established by carrying out microscale feedings at several conditions. Experiments were guided by thin layer chromatography and gas chromatography analysis. It was observed that the substrate should be added in ethanol at concentrations between 15 to 30 mg per 100 ml of medium. The extraction of the product showed to be more efficient when carried out from both mycelia and broth and using ethylacetate as the extracting solvent. The experiment should be stopped six days after feeding the substrate to the fungus for the best product yield.Condições otimizadas para a biotransformação de compostos diterpênicos pelo fungo Cephalosporium aphidicola foram determinadas, realizando-se incubações em microescala nas quais variaram-se parâmetros como o tempo de incubação e a quantidade de substrato adicionado. A velocidade (índice de bioconversão foi monitorada analisando-se os extratos de cultivo através de cromatografia em camada delgada e cromatografia gasosa. Os resultados obtidos mostraram que, para melhores rendimentos, o substrato deve ser adicionado em solução etanólica, na concentração de 15-30 mg por 100 mL de meio de cultura. A extração de produtos deve ser realizada com acetato de etila, a partir da fase aquosa e do micélio, no sexto dia após a adição do substrato. Estes resultados podem ser utilizados como um roteiro para incubações de compostos estruturalmente semelhantes com o fungo Cephalosporium aphidicola.

  13. Bioconversion of red ginseng saponins in the gastro-intestinal tract in vitro model studied by high-performance liquid chromatography-high resolution Fourier transform ion cyclotron resonance mass spectrometry

    NARCIS (Netherlands)

    Kong, H.; Wang, M.; Venema, K.; Maathuis, A.; Heijden, R. van der; Greef, J. van der; Xu, G.; Hankemeier, T.

    2009-01-01

    A high-performance liquid chromatography-high resolution Fourier transform ion cyclotron resonance mass spectrometry (HPLC-FTICR-MS) method was developed to investigate the metabolism of ginsenosides in in vitro models of the gastro-intestinal tract. The metabolites were identified by

  14. Bioconversion of Ginsenosides in the American Ginseng (西洋參 Xī Yáng Shēn Extraction Residue by Fermentation with Lingzhi (靈芝 Líng Zhī, Ganoderma Lucidum

    Directory of Open Access Journals (Sweden)

    Bo Yang Hsu

    2013-04-01

    Full Text Available Ginseng (人参 Rén Shēn has been widely employed in functional foods and traditional medicines in many Asian countries. Owing to the high consumer demand of ginseng products, a large amount of ginseng residue is generated after extraction of ginseng. However, the ginseng residue still contains many bioactive compounds such as ginsenosides. The objective of this research was to convert ginsenosides in American ginseng (西洋參 Xī Yáng Shēn extraction residue (AmR by fermentation with lingzhi (靈芝 Líng Zhī, Ganoderma lucidum and the fermentation products will be used for further hypoglycemic activity research. Thus, this study was primarily focused on the ginsenosides that have been reported to possess hypoglycemic activity. In this study, the changes in seven ginsenoside [Rg1, Re, Rb1, Rc, Rg3(S, compound K (CK, and Rh2(S] in the products as affected by fermentation were investigated. Our results showed that the levels of ginsenosides, namely, Rg1, Rg3(S, and CK increased, while the other ginsenosides (Re, Rb1, and Rc decreased during the fermentation process.

  15. A system for accurate on-line measurement of total gas consumption or production rates in microbioreactors

    NARCIS (Netherlands)

    van Leeuwen, Michiel; Heijnen, Joseph J.; Gardeniers, Johannes G.E.; Oudshoorn, Arthur; Noorman, Henk; Visser, Jan; van der Wielen, Luuk A.M.; van Gulik, Walter M.

    2009-01-01

    A system has been developed, based on pressure controlled gas pumping, for accurate measurement of total gas consumption or production rates in the nmol/min range, applicable for on-line monitoring of bioconversions in microbioreactors. The system was validated by carrying out a bioconversion with

  16. Kecernaan Nutrien pada Babi Lokal Periode Pertumbuhan yang Diberi Ransum Mengandung Biji Asam Biokonversi Spontan (NUTRIENTS DIGESTIBILITY IN GROWING LOCAL PIG FED WITH DIET COMPOSED OF SPONTENOUS BIOCONVERTED-TAMARIND SEED

    Directory of Open Access Journals (Sweden)

    Redempta Wea

    2018-01-01

    Full Text Available A research aimed to evaluate nutrients digestibility in growing local male pig fed spontaneous bioconverted-tamarind seed has been done in animal feed technology laboratory of Kupang State Agricultural Polytechnic.The research used 25 local male grower pigs with body weight around 3-6 kg. The study used a randomized block design with five treatments, i.e. R0 = ration using tamarind seeds without bioconversion, R1 = ration using spontaneous bioconversion tamarinds for 24 hours, R2 = rations using spontaneous bioconversion tamarinds for 48 hours, R3 = rations using bioconversion tamarinds spontaneous for 72 hours, and R4 = rations using spontaneous bioconversion tamarinds for 96 hours. Each treatment was repeated five times in which each of them used five pigs. Parameters observed were nutrient digestibility (dry matter, crude protein, crude fat, crude fiber, and ash. The data were analyzed by using variance and continued by Duncan’s multiple range test to determine the differences between treatments. The results showed that the time of spontaneous bioconversion of tamarind seeds increased the digestibility of tamarind seed nutrients and it was concluded that the best time of spontaneous bioconversion was for 72 hours.

  17. Agricultural feedstock and waste treatment and engineering

    Energy Technology Data Exchange (ETDEWEB)

    Fiechter, A

    1985-01-01

    The present volume covers the production of ethanol from Jerusalem artichoke, cheese whey and the bioconversion of humicellulose, as well as modelling of bioreactors, optimization and process control. Four chapters are separately treated. (EF). With 65 figs., 53 tabs.

  18. Nitrilase from rhodococcus rhodochrous ATCC BAA-870: fibre formation over time

    CSIR Research Space (South Africa)

    Frederick, J

    2008-07-01

    Full Text Available of a nitrile into its corresponding carboxylic acid and ammonia, and have become important industrial enzymes as a result of the products they afford. Successful commercial examples of nitrile bioconversion include production of nicotinic acid...

  19. Deproteination of shrimp shell wastes using immobilized marine associated pseudomonad Amet1776

    Digital Repository Service at National Institute of Oceanography (India)

    Bhagat, J.; Venkatramani, M.; Hussain, A. J.; Jayaprakashvel, M.

    in abundance in India in the last few years. The conventional demineralization, deproteination and decoloration method of extraction of chitin from crustacean waste is costly and causes environmental problems. In this study bioconversion of chitinous material...

  20. Cell Wall Diversity in Forage Maize

    NARCIS (Netherlands)

    Torres, A.F.; Noordam-Boot, C.M.M.; Dolstra, Oene; Weijde, van der Tim; Combes, Eliette; Dufour, Philippe; Vlaswinkel, Louis; Visser, R.G.F.; Trindade, L.M.

    2015-01-01

    Genetic studies are ideal platforms for assessing the extent of genetic diversity, inferring the genetic architecture, and evaluating complex trait interrelations for cell wall compositional and bioconversion traits relevant to bioenergy applications. Through the characterization of a forage

  1. Isolation and characterization of β-glucosidase producing bacteria ...

    African Journals Online (AJOL)

    Administrator

    2011-10-26

    Oct 26, 2011 ... lase enzyme system, along with endoglucanase and cellobiohydrolase. ... biomass substrates, for synthesis of useful glucosides, in flavor industry for ... 2007) and in the bioconversion of phenolic anti-oxidants from defatted ...

  2. Xylitol production by Debaryomyces hansenii and Candida guilliermondii from rapeseed straw hemicellulosic hydrolysate

    DEFF Research Database (Denmark)

    López-Linares, Juan Carlos; Romero, Inmaculada; Cara, Cristobal

    2018-01-01

    This study evaluated the possibility of using rapeseed straw hemicellulosic hydrolysate as a fermentation medium for xylitol production. Two yeast strains, namely Debaryomyces hansenii and Candida guilliermondii, were used for this bioconversion process and their performance to convert xylose...

  3. Acute toxicity and genotoxicity of fermented traditional medicine oyaksungi-san

    Directory of Open Access Journals (Sweden)

    Hwayong Park

    2017-06-01

    Conclusion: As a whole, no acute toxicity or genotoxicity were observed in all the assays examined. Therefore, fermented OY is considered to be a safe material that can be used for development of complementary and alternative medicine using bioconversion.

  4. Etudes du devenir de médicaments en milieu aqueux : synthèse, caractérisation et détection des produits de transformation biotique et abiotique par les procédés d’oxydation avancée et les bioconversions

    OpenAIRE

    Olvera Vargas , Hugo

    2014-01-01

    The present project contributes with valuable data for a better fundamental understanding on the fate of pharmaceutical residues in the environment, dealing with the main challenges concerning this increasingly worrying environmental issue. The used Electrochemical Advanced Oxidation Processes (EAOPs), electro-Fenton (EF) and anodic oxidation (AO), showed to be a very efficient alternative for the mineralization of acid solutions of the pharmaceuticals RNTD and FRSM, attaining almost complete...

  5. A microbial transformation using Bacillus subtilis B7-S to produce natural vanillin from ferulic acid.

    Science.gov (United States)

    Chen, Peng; Yan, Lei; Wu, Zhengrong; Li, Suyue; Bai, Zhongtian; Yan, Xiaojuan; Wang, Ningbo; Liang, Ning; Li, Hongyu

    2016-02-04

    Bacillus subtilis strain B7-S screened from18 strains is an aerobic, endospore-forming, model organism of Gram-positive bacteria which is capable to form vanillin during ferulic acid bioconversion. The bioconversion of ferulic acid to vanillin by Bacillus subtilis B7-S (B. subtilis B7-S) was investigated. Based on our results, the optimum bioconversion conditions for the production of vanillin by B. subtilis B7-S can be summarized as follows: temperature 35 °C; initial pH 9.0; inoculum volume 5%; ferulic acid concentration 0.6 g/L; volume of culture medium 20%; and shaking speed 200 r/min. Under these conditions, several repeated small-scale batch experiments showed that the maximum conversion efficiency was 63.30% after 3 h of bioconversion. The vanillin products were confirmed by spectral data achieved from UV-vis, inductively coupled plasma atomic emission spectroscope (ICP-AES) and Fourier transform infrared spectrometer (FT-IR) spectra. Scanning electron microscopy (SEM) and transmission electron spectroscopy (TEM) results confirmed that the cell surface of B. subtilis plays a role in the induction of ferulic acid tolerance. These results demonstrate that B. subtilis B7-S has the potential for use in vanillin production through bioconversion of ferulic acid.

  6. Overview of technical barriers and implementation of cellulosic ethanol in the U.S

    International Nuclear Information System (INIS)

    Kim, Tae Hoon; Kim, Tae Hyun

    2014-01-01

    There is mounting concern about the buildup of carbon dioxide (CO 2 ) and other so-called greenhouse gases in the atmosphere. In general, bioethanol production requires minimal fossil fuel input in the conversion step, and ethanol is considered a promising alternative fuel to petroleum-derived products. It is anticipated that ethanol production with second-generation biomass, i.e. lignocellulosic materials, will be possible on a large scale in the near future. Latest efforts have been focused on overcoming technical challenges in bioconversion, particularly pretreatment, and finding the solutions required to implement biorefinery on a large scale. This paper introduces and reviews the current status of research, and of the ethanol industry in the U.S. In addition, other important concepts in biofuels, cellulosic ethanol, and biorefinery in general are reviewed, and the key technical issues in bioconversion of cellulosic ethanol, such as pretreatment and factors affecting bioconversion of biomass are also discussed. - Highlights: • The current status of research, and of the ethanol industry in the U.S. • Important concepts in biofuels, cellulosic ethanol, and biorefinery. • The key technical issues in bioconversion of cellulosic ethanol. • Pretreatment and factors affecting bioconversion of biomass

  7. Designer biomass for next-generation biorefineries: leveraging recent insights into xylan structure and biosynthesis.

    Science.gov (United States)

    Smith, Peter J; Wang, Hsin-Tzu; York, William S; Peña, Maria J; Urbanowicz, Breeanna R

    2017-01-01

    Xylans are the most abundant noncellulosic polysaccharides in lignified secondary cell walls of woody dicots and in both primary and secondary cell walls of grasses. These polysaccharides, which comprise 20-35% of terrestrial biomass, present major challenges for the efficient microbial bioconversion of lignocellulosic feedstocks to fuels and other value-added products. Xylans play a significant role in the recalcitrance of biomass to degradation, and their bioconversion requires metabolic pathways that are distinct from those used to metabolize cellulose. In this review, we discuss the key differences in the structural features of xylans across diverse plant species, how these features affect their interactions with cellulose and lignin, and recent developments in understanding their biosynthesis. In particular, we focus on how the combined structural and biosynthetic knowledge can be used as a basis for biomass engineering aimed at developing crops that are better suited as feedstocks for the bioconversion industry.

  8. Biotransformation and removal of sulfur from dibenzothiophene using improved bio catalytic methods

    International Nuclear Information System (INIS)

    La Rotta, C. E; Mora, A.L; Madero, A; Mogollon, L.I

    1998-01-01

    Three methods for the removal of sulfur from dibenzothiophene were evaluated using bio catalytic processes. The methods were a microbial, an enzymatic and a combined one that involves a previous enzymatic oxidation followed by microbial degradation. The bioconversion was evaluated over the molecular dibenzothiophene model, obtaining higher bioconversion percentages through the combined method. The microorganisms used in this study correspond to several Colombian indigenous strains isolated by direct methods from natural sources, and using a standard strain as positive control. All strains have shown sulfur removal capacity, and organic solvent tolerance. The enzyme used was a hemo protein with peroxidase activity, Cytochrome C, obtained from equine heart

  9. A Multidisciplinary Approach Toward the Rapid and Preparative-Scale Biocatalytic Synthesis of Chiral Amino Alcohols: A Concise Transketolase-/omega-Transaminase-Mediated Synthesis of (2S,3S)-2-Aminopentane-1,3-diol

    DEFF Research Database (Denmark)

    Smith, M.E.B; Chen, B.H.; Hibbert, E.G

    2010-01-01

    Chiral amino alcohols represent an important class of value-added biochemicals and pharmaceutical intermediates. Chemical routes to such compounds are generally step intensive, requiring environmentally unfriendly catalysts and solvents. This work describes a multidisciplinary approach to the rapid...... the bioconversions were subsequently scaled up to preparative scales in batch stirred-tank reactors. The microwell methods thus provide process chemists and engineers with a valuable tool for the rapid and early evaluation of potential synthetic strategies. Overall, this work describes a concise and efficient...... biocatalytic route to chiral amino alcohols and illustrates an integrated multidisciplinary approach to bioconversion process design and scale-up....

  10. Enzymes and microorganisms in food industry waste processing and conversion to useful products: literature review

    Energy Technology Data Exchange (ETDEWEB)

    Carroad, P A [Univ. of California, Davis; Wilke, C R

    1978-01-01

    Bioconversion of food processing wastes is receiving increased attention with the realization that waste components represent an available and utilizable resource for conversion to useful products. Liquid wastes are characterized as dilute streams containing sugars, starches, proteins and fats. Solid wastes are generally cellulosic, but may contain other polymers. The greatest potential for economic bioconversion is represented by processes to convert cellulose to glucose, glucose to alcohol and protein, starch to invert sugar, and dilute waste streams to methane by anaerobic digestion. Microbial or enzymatic processes to accomplish these conversions are described.

  11. Advances in energy and environment. Vol. 1: Energy

    International Nuclear Information System (INIS)

    El-Sharkawy, A.L.; Kummler, R.H.

    1996-01-01

    The 5th conference of energy and environment was held on 3-6 June 1996 in Cairo. The specialists discussed the effects of advances in energy and environment. The applications of solar energy, heat transfer, thermal application, storage and bio-conversion, fuels, energy and development. Studies were discussed at the meeting and more than 1000 papers were presented. This first volume covers papers presented on the following topics: solar thermal, heat transfer and thermal applications, storage and bio-conversion, refrigeration and iar conditioning, combustion, fuels and engines, energy and development. tabs., figs

  12. Enantioselective hydrolysis of epichlorohydrin using whole ...

    Indian Academy of Sciences (India)

    2012-08-11

    Aug 11, 2012 ... 2Engineering Research Center of Bioconversion and Biopurification of Ministry ... in the production of enantiopure (S)-epichlorohydrin by epoxide .... was cultured in a 500 mL flask containing 100 mL liquid ... for different times without shaking. ..... epichlorohydrin compared to that of the (R)-epichlorohydrin.

  13. The significance of the initiation process parameters and reactor design for maximizing the efficiency of microbial fuel cells

    DEFF Research Database (Denmark)

    Sun, Guotao; Thygesen, Anders; Ale, Marcel Tutor

    2014-01-01

    Microbial fuel cells (MFCs) can be used for electricity generation via bioconversion of wastewater and organic waste substrates. MFCs also hold potential for production of certain chemicals, such as H2 and H2O2. The studies of electricity generation in MFCs have mainly focused on the microbial co...

  14. Ammonia inhibition on hydrogen enriched anaerobic digestion of manure under mesophilic and thermophilic conditions

    DEFF Research Database (Denmark)

    Wang, Han; Zhang, Yifeng; Angelidaki, Irini

    2016-01-01

    Capturing of carbon dioxide by hydrogen derived from excess renewable energy (e.g., wind mills) to methane in a microbially catalyzed process offers an attractive technology for biogas production and upgrading. This bioconversion process is catalyzed by hydrogenotrophic methanogens, which are kno...

  15. Browse Title Index

    African Journals Online (AJOL)

    Vol 12, No 47 (2013), Bioconversion of ferulic acid to vanillin by combined action of Aspergillus niger K8 and Phanerochaete crysosporium ATCC 24725, Abstract ... of rice straw by thermotolerant cellulolytic Streptomyces viridiochromogenes under solid-state fermentation conditions for bioethanol production, Abstract PDF.

  16. Author Details

    African Journals Online (AJOL)

    Motedayen, Nazila. Vol 12, No 47 (2013) - Articles Bioconversion of ferulic acid to vanillin by combined action of Aspergillus niger K8 and Phanerochaete crysosporium ATCC 24725. Abstract PDF. ISSN: 1684-5315. AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors · FAQ's ...

  17. African Journal of Biotechnology - Vol 12, No 47 (2013)

    African Journals Online (AJOL)

    Bioconversion of ferulic acid to vanillin by combined action of Aspergillus niger K8 and Phanerochaete crysosporium ATCC 24725 · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. Nazila Motedayen, Maznah B. T. Ismail, Forough Nazarpour, 6618-6624 ...

  18. Utilization of geothermal energy for methane production for J. A. Albertson Land and Cattle Company. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1980-07-01

    The feasibility of an integrated system to utilize a geothermal resource for a bioconversion plant. This integrated facility would use the manure from approximately 30,000 head of feedlot cattle as a feedstock for an anaerobic digestion plant. The findings on engineering design, geological assessment, environmental, economic, and institutional requirements of the proposed project are summarized. (MHR)

  19. Statistical optimization of process parameters for the production of ...

    African Journals Online (AJOL)

    In this study, optimization of process parameters such as moisture content, incubation temperature and initial pH (fixed) for the improvement of citric acid production from oil palm empty fruit bunches through solid state bioconversion was carried out using traditional one-factor-at-a-time (OFAT) method and response surface ...

  20. Polyethylene glycol (PEG)-mediated transformation of the fused egfp ...

    African Journals Online (AJOL)

    Yomi

    2012-03-06

    Mar 6, 2012 ... pUC19 vector. Enhanced green fluorescent protein-encoding gene (egfp) and a selection marker, the hygromycin ... agro-industrial waste bioconversion (Shabtay et al., 2009;. Salvachúa et al., 2011); and .... gene, two pairs of primers were designed based on the Lentinula edodes sequences published by ...

  1. Second generation bioethanol production from Saccharum spontaneum L. ssp. aegyptiacum (Willd.) Hack.

    Science.gov (United States)

    Danilo Scordia; Salvatore L. Consentino; Thomas W. Jeffries

    2010-01-01

    Saccharum (Saccharum spontaneum L. ssp. aegyptiacum (Willd.) Hack.), is a rapidly growing, wide ranging high-yield perennial, suitable for second generation bioethanol production. This study evaluated oxalic acid as a pretreatment for bioconversion. Overall sugar yields, sugar degradation products, enzymatic glucan hydrolysis and ethanol production were studied as...

  2. Effects of sodium lactate and lactic acid on chemical, microbiological ...

    African Journals Online (AJOL)

    Administrator

    2011-09-19

    Sep 19, 2011 ... 2Laboratory of Enzymes and Bioconversion, Road of Soukra, B.P.W, ... opportunities for the poultry industrial production for using efficient, ... In industry, marinades are based on weak acids ... cost natural substrates, this study postulates that LA and ..... Furthermore, SL is widely available, economic and.

  3. Yeast metabolic engineering for hemicellulosic ethanol production

    Science.gov (United States)

    Jennifer Van Vleet; Thomas W. Jeffries

    2009-01-01

    Efficient fermentation of hemicellulosic sugars is critical for the bioconversion of lignocellulosics to ethanol. Efficient sugar uptake through the heterologous expression of yeast and fungal xylose/glucose transporters can improve fermentation if other metabolic steps are not rate limiting. Rectification of cofactor imbalances through heterologous expression of...

  4. Lignocellulosic biomass utilization toward biorefinery using meshophilic Clostridial species

    NARCIS (Netherlands)

    Tamaru, Yutaka; Lopez Contreras, A.M.

    2013-01-01

    Lignocellulosic biomass such as agricultural, industrial, and forestry residues as well as
    dedicated crops constitute renewable and abundant resources with great potential for a lowcost
    and uniquely sustainable bioconversion to value-added bioproducts. Thus, many
    organic fuels and

  5. Influence of dietary spices on the in vivo absorption of ingested β-carotene in experimental rats.

    Science.gov (United States)

    Veda, Supriya; Srinivasan, Krishnapura

    2011-05-01

    Animal studies were conducted to evaluate the influence of dietary spice compounds, piperine, capsaicin and ginger, on the absorption of orally administered β-carotene and its conversion to vitamin A. In rats maintained on these spice-containing diets for 8 weeks, concentrations of β-carotene and retinol were determined in the serum, liver and intestine 4 h after a single oral administration of β-carotene. β-Carotene concentration was significantly increased in the serum, liver and intestine of piperine- and ginger-fed rats, suggesting improved absorption of β-carotene. However, retinol concentration was not significantly changed in these animals, suggesting that the bioconversion of β-carotene to vitamin A was not similarly influenced. Between the two enzymes involved in the bioconversion of β-carotene to vitamin A, the activity of intestinal and hepatic β-carotene 15,15'-dioxygenase was either unaffected or lowered by these spice treatments. The activity of intestinal and hepatic retinal reductase was unaffected by the dietary spices. Activities of these two enzymes involved in the bioconversion of β-carotene to retinal were inhibited by the test spices in vitro, thus corroborating with the in vivo observation. Although the bioconversion of β-carotene was not promoted, increased absorption and tissue levels of β-carotene by the dietary spices may contribute to a higher antioxidant protection.

  6. Impact of Diet on Human Intestinal Microbiota and Health

    NARCIS (Netherlands)

    Salonen, A.; Vos, de W.M.

    2014-01-01

    Our intestinal microbiota is involved in the breakdown and bioconversion of dietary and host components that are not degraded and taken up by our own digestive system. The end products generated by our microbiota fuel our enterocytes and support growth but also have signaling functions that generate

  7. RNA-seq analysis of Pichia anomala reveals important mechanisms required for survival at low pH

    DEFF Research Database (Denmark)

    Fletcher, Eugene; Feizi, Amir; Kim, SungSoo

    2015-01-01

    Background: The product yield and titers of biological processes involving the conversion of biomass to desirable chemicals can be limited by environmental stresses encountered by the microbial hosts used for the bioconversion. One of these main stresses is growth inhibition due to exposure to lo...

  8. Nitrification in trickling filters applied to the post-treatment of effluents from UASB reactor: correlation between ammonia removal and the relative abundance of nitrifying bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Missagia, B. S.; Almeida, P. G. S. de; Silva, S. Q.; Chernicharo, C. A. L.

    2009-07-01

    The number and physiological activity of nitrifying bacteria in wastewater treatment reactors are considered the ratelimiting parameters for the bioconversion of nitrogen in sewage. Since the presence of ammonia and nitrite oxidizers can be correlated with their activity. In situ probe counts can be correlated with the nitrification rates in order to compare the efficiency of different media types. (Author)

  9. FY 2000 report on the results of the R and D of the technology for rationalization of energy utilization and for CO2 fixation using recycled paper; 2000 nendo energy shiyo gorika koshi nado yuko riyo nisanka tanso koteika gijutsu kenkyu kaihatsu seika hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    In this R and D, the recycled paper, etc. composed mainly of cellulose are degraded (saccharified) up to saccharides in a biological method. The saccharides and CO2 obtained are converted into useful substances such as organic acid using the bacterium function. The aim of the R and D is to develop this conversion (bioconversion) technology and to establish the technology to make an effective use of the recycled paper, etc. as useful chemical raw materials/substances and energy. In FY 2000, study was made mostly of the saccharification and bioconversion. As to the saccharification, conducted were the collection of the bacteria for cellulose degrading enzyme production which have been found so far and the evaluation of degradation of the recycled paper. And, as to the bioconversion, conducted were the survey and isolation of enzyme proteins and genes which are concerned in it in the process toward the formation to organic acid from saccharides and CO2, and the analysis of part of them. In this report, introductory remarks were described in Chapter 1. In Chapter 2, the results were summarized of the study on saccharification of the recycled paper. In Chapter 3, the results were outlined of the study on the bioconversion technology. This technology development was aimed at establishing new high efficiency bio-processes. (NEDO)

  10. Nitrification in trickling filters applied to the post-treatment of effluents from UASB reactor: correlation between ammonia removal and the relative abundance of nitrifying bacteria

    International Nuclear Information System (INIS)

    Missagia, B. S.; Almeida, P. G. S. de; Silva, S. Q.; Chernicharo, C. A. L.

    2009-01-01

    The number and physiological activity of nitrifying bacteria in wastewater treatment reactors are considered the ratelimiting parameters for the bioconversion of nitrogen in sewage. Since the presence of ammonia and nitrite oxidizers can be correlated with their activity. In situ probe counts can be correlated with the nitrification rates in order to compare the efficiency of different media types. (Author)

  11. Comparative production of cellulases by mutants of Trichoderma parceramosume PTCC5140

    Directory of Open Access Journals (Sweden)

    Hoda Nouri

    2017-06-01

    Discussion and conclusion: Evaluation of cellulase production in mutant strains of Trichoderma parceramosume PTCC 5140 showed that use of chemical mutagenesis with 2 to 11 fold increasing in enzyme activity is a potent method to improve cellulase complex activity. In the current study, obtained mutant strains could be introduced as a potent cellulase producer for further studies in bioconversion processes.

  12. Biological conversion system

    Science.gov (United States)

    Scott, C.D.

    A system for bioconversion of organic material comprises a primary bioreactor column wherein a biological active agent (zymomonas mobilis) converts the organic material (sugar) to a product (alcohol), a rejuvenator column wherein the biological activity of said biological active agent is enhanced, and means for circulating said biological active agent between said primary bioreactor column and said rejuvenator column.

  13. Oyster mushrooms ( Pleurotus ) are useful for utilizing lignocellulosic ...

    African Journals Online (AJOL)

    The biodegradation and bioconversion of agro wastes (lignin, cellulose and hemicellulose) could have vital implication in cleaning our environment. The bioprocessing of lignin depends on the potent lignocellulolytic enzymes such as phenol oxidases (laccase) or heme peroxidases (lignin peroxidase (LiP), manganese ...

  14. Nile perch fish processing waste along Lake Victoria in East Africa ...

    African Journals Online (AJOL)

    In East Africa, Nile perch fish processing into chilled fish fillet for export along Lake Victoria generate large proportions of both solid and liquid wastes. However, no thorough auditing and characterization of the waste has been done that would guide potential value addition through bioconversions and waste management.

  15. Improvement in the nutritive quality of cassava and its by-products ...

    African Journals Online (AJOL)

    A review of the extent of fermentation of cassava and its by-products was made in order to highlight the role played by fermentation on the bio-conversion of cassava and cassava by-products for improved nutrient quality. The reasons for cassava products fermentation mentioned were synonymous with the reasons ...

  16. High-yield continuous production of nicotinic acid via nitrile hydratase–amidase cascade reactions using cascade CSMRs

    Czech Academy of Sciences Publication Activity Database

    Cantarella, L.; Gallifuoco, A.; Malandra, A.; Martínková, Ludmila; Spera, A.; Cantarella, M.

    2011-01-01

    Roč. 48, 4-5 (2011), 345-350 ISSN 0141-0229 R&D Projects: GA MŠk OC09046 Institutional research plan: CEZ:AV0Z50200510 Keywords : Nitrile hydratase-amidase cascade system * 3-Cyanopyridine bioconversion * Nicotinic acid Subject RIV: EE - Microbiology, Virology Impact factor: 2.367, year: 2011

  17. Biocatalytic material comprising multilayer enzyme coated fiber

    Science.gov (United States)

    Kim, Jungbae [Richland, WA; Kwak, Ja Hun [Richland, WA; Grate, Jay W [West Richland, WA

    2009-11-03

    The present invention relates generally to high stability, high activity biocatalytic materials and processes for using the same. The materials comprise enzyme aggregate coatings having high biocatalytic activity and stability useful in heterogeneous environment. These new materials provide a new biocatalytic immobilized enzyme system with applications in bioconversion, bioremediation, biosensors, and biofuel cells.

  18. Anaerobic digestion of macroalgae: methane potentials, pre-treatment, inhibition and co-digestion

    DEFF Research Database (Denmark)

    Bangsø Nielsen, Henrik; Heiske, Stefan

    2011-01-01

    In the present study we tested four macroalgae species – harvested in Denmark – for their suitability of bioconversion to methane. In batch experiments (53 WC) methane yields varied from 132 ml g volatile solids1 (VS) for Gracillaria vermiculophylla, 152 ml g VS1 for Ulva lactuca, 166 ml g VS1...

  19. Development of a two-step “green” synthesis for (-)-ambafuran production

    CSIR Research Space (South Africa)

    Steenkamp, Lucia H

    2010-09-01

    Full Text Available The main objective of the development of a two-step “green” synthesis for (-)-ambafuran production is to find an alternative synthesis of (-) Ambrox from sclareol, to use a bioconversion or biocatalysis route, and that it results in a natural...

  20. Air-Filled porosity and permeability relationships during solid-waste fermentation

    NARCIS (Netherlands)

    Richard, T.L.; Veeken, A.H.M.; Wilde, de V.; Hamelers, H.V.M.

    2004-01-01

    An experimental apparatus was constructed to measure the structural parameters of organic porous media, i.,e. mechanical strength, air-filled porosity, air permeability, and the Ergun particle size. These parameters are critical to the engineering of aerobic bioconversion systems and were measured

  1. Population-based nutrikinetic modeling of polyphenol exposure

    NARCIS (Netherlands)

    van Velzen, E.J.J.; Westerhuis, J.A.; Grün, C.H.; Jacobs, D.M.; Eilers, P.H.C.; Mulder, Th.P.; Foltz, M.; Garczarek, U.; Kemperman, R.; Vaughan, E. E.; van Duynhoven, J.P.M.; Smilde, A.K.

    2014-01-01

    The beneficial health effects of fruits and vegetables have been attributed to their polyphenol content. These compounds undergo many bioconversions in the body. Modeling polyphenol exposure of humans upon intake is a prerequisite for understanding the modulating effect of the food matrix and the

  2. Population-based nutrikinetic modelling of phytochemical exposure

    NARCIS (Netherlands)

    Velzen, van E.J.J.; Westerhuis, J.A.; Grün, C.H.; Duynhoven, van J.P.M.; Jacobs, D.M.; Eilers, P.H.C.; Mulder, T.P.; Foltz, M.; Garczarek, U.; Kemperman, R.; Vaughan, E.E.; Smilde, A.K.

    2014-01-01

    The beneficial health effects of fruits and vegetables have been attributed to their polyphenol content. These compounds undergo many bioconversions in the body. Modeling polyphenol exposure of humans upon intake is a prerequisite for understanding the modulating effect of the food matrix and the

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

    Science.gov (United States)

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

    2013-01-01

    Thermochemical pretreatment of lignocellulose is crucial to bioconversion in the fields of biorefinery and biofuels. However, the enzyme inhibitors in pretreatment hydrolysate make solid substrate washing and hydrolysate detoxification indispensable prior to enzymatic hydrolysis. Sulfite pretreatment to overcome recalcitrance of lignocelluloses (SPORL) is a relatively...

  4. Overexpression, purification and characterization of the Aspergillus ...

    African Journals Online (AJOL)

    Cellulases are industrially important hydrolytic enzymes applicable in the bioconversion of cellulosic biomass to simple sugars. In this work, an endoglucanase from Aspergillus niger ATCC 10574, EglA, was expressed in the methylotrophic yeast Pichia pastoris and the properties of the recombinant protein were ...

  5. Efficient conversion of pretreated brewer's spent grain and wheat bran by submerged cultivation of Hericium erinaceus.

    Science.gov (United States)

    Wolters, Niklas; Schabronath, Christoph; Schembecker, Gerhard; Merz, Juliane

    2016-12-01

    Brewer's spent grain (BSG) and wheat bran (WB) are industrial byproducts that accumulate in millions of tons per year and are typically applied as animal feed. Since both byproducts show a great potential as substrates for fermentation, the approach developed in this study consists of utilizing these lignocellulosic byproducts for biomass production of the medicinal fungus Hericium erinaceus through submerged cultivation. To increase the biological efficiency of the bioconversion, acidic pretreatment was applied yielding a bioconversion of 38.6% for pretreated BSG and 34.8% for pretreated WB. This study shows that the complete degradation of (hemi)cellulose into monosaccharides was not required for an efficient bioconversion. The produced fungal biomass was applied in a second fermentation step to induce the secondary metabolite erinacine C production. Thus, biomass was produced as a functional food ingredient with erinacine C contents of 174.8mg/g for BSG and 99.3mg/g for WB based bioconversions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. 11 β-Hydroxylation of cortexolone using immobilized ...

    African Journals Online (AJOL)

    reda

    2012-06-12

    Jun 12, 2012 ... Transformation of cortexolone to cortisol and prednisolone by the filamentous fungus Cunninghamella elegans ... The highest bioconversion efficiency was recorded with sodium citrate (1 g/L) and sodium benzoate (1 g/L). Similarly ... transferred to 50 ml of 0.8 MgSO4 in citrate-phosphate buffer, at pH. 4.2.

  7. Development of advanced biorefinery concepts using magnetically responsive materials

    Czech Academy of Sciences Publication Activity Database

    Šafařík, Ivo; Pospišková, K.; Baldíková, E.; Šafaříková, Miroslava

    2016-01-01

    Roč. 116, DEC (2016), s. 17-26 ISSN 1369-703X R&D Projects: GA ČR GA13-13709S Institutional support: RVO:67179843 Keywords : saccharomyces-cerevisiae cells * solid acid catalysts * Separation * Biocatalysis * Immobilization * Bioconversion * Magnetic particles * Magnetic enzymes and cells Subject RIV: EH - Ecology, Behaviour Impact factor: 2.892, year: 2016

  8. Development of advanced biorefinery concepts using magnetically responsive materials

    Czech Academy of Sciences Publication Activity Database

    Šafařík, Ivo; Pospíšková, K.; Baldíková, E.; Šafaříková, Miroslava

    2016-01-01

    Roč. 116, SI (2016), s. 17-26 ISSN 1369-703X Institutional support: RVO:60077344 Keywords : separation * biocatalysis * immobilization * bioconversion * magnetic particles * magnetic enzymes and cells Subject RIV: GM - Food Processing Impact factor: 2.892, year: 2016

  9. Recombinant Saccharomyces cerevisiae expressing P450 in artificial digestive systems : A model for biodetoxication in the human digestive environment

    NARCIS (Netherlands)

    Blanquet, S.; Meunier, J.P.; Minekus, M.; Marol-Bonnin, S.; Alric, M.

    2003-01-01

    The use of genetically engineered microorganisms such as bacteria or yeasts as live vehicles to carry out bioconversion directly in the digestive environment is an important challenge for the development of innovative biodrugs. A system that mimics the human gastrointestinal tract was combined with

  10. Biotransformation of Domestic Wastewater Treatment Plant Sludge by Two-Stage Integrated Processes -Lsb & Ssb

    Directory of Open Access Journals (Sweden)

    Md. Zahangir Alam, A. H. Molla and A. Fakhru’l-Razi

    2012-10-01

    Full Text Available The study of biotransformation of domestic wastewater treatment plant (DWTP sludge was conducted in laboratory-scale by two-stage integrated process i.e. liquid state bioconversion (LSB and solid state bioconversion (SSB processes. The liquid wastewater sludge [4% w/w of total suspended solids (TSS] was treated by mixed filamentous fungi Penicillium corylophilum and Aspergillus niger, isolated, screened and mixed cultured in terms of their higher biodegradation potential to wastewater sludge. The biosolids was increased to about 10% w/w. Conversely, the soluble [i.e. Total dissolve solid (TDS] and insoluble substances (TSS in treated supernatant were decreased effectively in the LSB process. In the developed LSB process, 93.8 g kg-1of biosolids were enriched with fungal biomass protein and nutrients (NPK, and 98.8% of TSS, 98.2% of TDS, 97.3% of turbidity, 80.2% of soluble protein, 98.8% of reducing sugar and 92.7% of chemical oxygen demand (COD in treated sludge supernatant were removed after 8 days of treatment. Specific resistance to filtration (1.39x1012 m/kg was decreased tremendously by the microbial treatment of DWTP sludge after 6 days of fermentation. The treated biosolids in DWTP sludge was considered as pretreated resource materials for composting and converted into compost by SSB process. The SSB process was evaluated for composting by monitoring the microbial growth and its subsequent roles in biodegradation in composting bin (CB. The process was conducted using two mixed fungal cultures, Trichoderma harzianum with Phanerochaete chrysosporium 2094 and (T/P and T. harzianum and Mucor hiemalis (T/M; and two bulking materials, sawdust (SD and rice straw (RS. The most encouraging results of microbial growth and subsequent solid state bioconversion were exhibited in the RS than the SD. Significant decrease of the C/N ratio and germination index (GI were attained as well as the higher value of glucosamine was exhibited in compost; which

  11. Hydroxylative activity of Aspergillus niger towards androst-4-ene and androst-5-ene steroids.

    Science.gov (United States)

    Świzdor, Alina; Panek, Anna; Milecka-Tronina, Natalia

    2017-10-01

    Aspergillus niger, one of fungal species most frequently used for experimental and industrial-scale biotransformations of various organic compounds, is generally known to transform steroids at 16β position. In this work, application of the strain A. niger KCH910 to bioconversion of dehydroepiandrosterone (DHEA), androstenediol and testosterone is described, with emphasis on the metabolic steps leading to the products. Evidence from this study indicated that incubated 5-ene steroids underwent bioconversion within two metabolic pathways: oxidation by the action of 3β-HSD (3β-hydroxysteroid dehydrogenase) to 4-ene steroids, and minor allylic hydroxylation to epimeric 7-alcohols. Further transformation of the 3-oxo-4-ene metabolites resulted in non-selective 16-hydroxylation. It is the first report on an A. niger strain able to introduce not only 16β- but also 16α-hydroxyl function into steroids. Copyright © 2017. Published by Elsevier Inc.

  12. Miniaturization in Biocatalysis

    Directory of Open Access Journals (Sweden)

    Pedro Fernandes

    2010-03-01

    Full Text Available The use of biocatalysts for the production of both consumer goods and building blocks for chemical synthesis is consistently gaining relevance. A significant contribution for recent advances towards further implementation of enzymes and whole cells is related to the developments in miniature reactor technology and insights into flow behavior. Due to the high level of parallelization and reduced requirements of chemicals, intensive screening of biocatalysts and process variables has become more feasible and reproducibility of the bioconversion processes has been substantially improved. The present work aims to provide an overview of the applications of miniaturized reactors in bioconversion processes, considering multi-well plates and microfluidic devices, update information on the engineering characterization of the hardware used, and present perspective developments in this area of research.

  13. Enhanced vanillin production from ferulic acid using adsorbent resin.

    Science.gov (United States)

    Hua, Dongliang; Ma, Cuiqing; Song, Lifu; Lin, Shan; Zhang, Zhaobin; Deng, Zixin; Xu, Ping

    2007-03-01

    High vanillin productivity was achieved in the batch biotransformation of ferulic acid by Streptomyces sp. strain V-1. Due to the toxicity of vanillin and the product inhibition, fed-batch biotransformation with high concentration of ferulic acid was unsuccessful. To solve this problem and improve the vanillin yield, a biotransformation strategy using adsorbent resin was investigated. Several macroporous adsorbent resins were chosen to adsorb vanillin in situ during the bioconversion. Resin DM11 was found to be the best, which adsorbed the most vanillin and the least ferulic acid. When 8% resin DM11 (wet w/v) was added to the biotransformation system, 45 g l(-1) ferulic acid could be added continually and 19.2 g l(-1) vanillin was obtained within 55 h, which was the highest vanillin yield by bioconversion until now. This yield was remarkable for exceeding the crystallization concentration of vanillin and therefore had far-reaching consequence in its downstream processing.

  14. Bioassays for risk assessment of coal conversion products

    Energy Technology Data Exchange (ETDEWEB)

    Schacht, S.; Sinder, C.; Pfeifer, F.; Klein, J. [DMT-Gesellschaft fuer Forschung und Pruefung mbH, Essen (Germany)

    1999-07-01

    Traditional as well as biotechnological processing coal leads to complex mixtures of products. Besides chemical and physical characterization, which provides the information for product application, there is a need for bioassays to monitor properties that are probably toxic, mutagenic or cancerogenic. Investigations carried out focused on the selection, adaptation and validation of bioassays for the sensitive estimation of toxic effects. Organisms like bacteria, Daphnia magna and Scenedesmus subspicatus, representing different complexities in the biosphere, were selected as test systems for ecotoxicological and mutagenicity studies. The results obtained indicate that bioassays are, in principle, suitable tools for characterization and evaluation of coal-derived substances and bioconversion products. Using coal products, coal-relevant model compounds and bioconversion products, data for risk assessment are presented. (orig.)

  15. Changes in brown coal structure caused by coal-solubilizing microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Schmiers, H.; Koepsel, R.; Weber, A.; Winkelhoefer, M.; Grosse, S. [Technische Univ. Bergakademie Freiberg (Germany). Inst. fuer Energieverfahrenstechnik und Chemieingenieurwesen

    1997-12-31

    The phenomenon of coal solubilization caused by microorganisms has been explained by various mechanisms: extraction of non-covalently bonded polar components of the coal substance by biogenic agents (chelating agents, alkaline substances) and enzyme-catalyzed cleavage of covalent bonds by extracellular enzyme systems. For this it is assumed that bond cleavage occurs on the aliphatic carbon (methylene groups, aliphatic bridges or on ester groups). As the coal has usually been treated with oxidizing agents such as H{sub 2}O{sub 2} or HNO{sub 3} before bioconversion, there is a possibility that the result of bioconversion is overlaid with the effect of the chemical treatment. We therefore studied the structural changes in the organic coal substance during pre-oxidation with H{sub 2}O{sub 2}, treatment with MnP and conversion using the fungal strains of Trichoderma and Fusarium oxysporum. (orig.)

  16. Thermochemical pretreatments for enhancing succinic acid production from industrial hemp (Cannabis sativa L.).

    Science.gov (United States)

    Gunnarsson, Ingólfur B; Kuglarz, Mariusz; Karakashev, Dimitar; Angelidaki, Irini

    2015-04-01

    The aim of this study was to develop an efficient thermochemical method for treatment of industrial hemp biomass, in order to increase its bioconversion to succinic acid. Industrial hemp was subjected to various thermochemical pretreatments using 0-3% H2SO4, NaOH or H2O2 at 121-180°C prior to enzymatic hydrolysis. The influence of the different pretreatments on hydrolysis and succinic acid production by Actinobacillus succinogenes 130Z was investigated in batch mode, using anaerobic bottles and bioreactors. Enzymatic hydrolysis and fermentation of hemp material pretreated with 3% H2O2 resulted in the highest overall sugar yield (73.5%), maximum succinic acid titer (21.9 g L(-1)), as well as the highest succinic acid yield (83%). Results obtained clearly demonstrated the impact of different pretreatments on the bioconversion efficiency of industrial hemp into succinic acid. Copyright © 2015. Published by Elsevier Ltd.

  17. Optimization of Arundo donax Saccharification by (Hemicellulolytic Enzymes from Pleurotus ostreatus

    Directory of Open Access Journals (Sweden)

    Rossana Liguori

    2015-01-01

    Full Text Available An enzymatic mixture of cellulases and xylanases was produced by Pleurotus ostreatus using microcrystalline cellulose as inducer, partially characterized and tested in the statistical analysis of Arundo donax bioconversion. The Plackett-Burman screening design was applied to identify the most significant parameters for the enzymatic hydrolysis of pretreated A. donax. As the most significant influence during the enzymatic hydrolysis of A. donax was exercised by the temperature (°C, pH, and time, the combined effect of these factors in the bioconversion by P. ostreatus cellulase and xylanase was analyzed by a 33 factorial experimental design. It is worth noting that the best result of 480.10 mg of sugars/gds, obtained at 45°C, pH 3.5, and 96 hours of incubation, was significant also when compared with the results previously reached by process optimization with commercial enzymes.

  18. Thermochemical pretreatments for enhancing succinic acid production from industrial hemp (Cannabis sativa L.)

    DEFF Research Database (Denmark)

    Gunnarsson, Ingólfur Bragi; Kuglarz, Mariusz; Karakashev, Dimitar Borisov

    2015-01-01

    The aim of this study was to develop an efficient thermochemical method for treatment of industrial hemp biomass, in order to increase its bioconversion to succinic acid. Industrial hemp was subjected to various thermochemical pretreatments using 0-3% H2SO4, NaOH or H2O2 at 121-180°C prior...... to enzymatic hydrolysis. The influence of the different pretreatments on hydrolysis and succinic acid production by Actinobacillus succinogenes 130Z was investigated in batch mode, using anaerobic bottles and bioreactors. Enzymatic hydrolysis and fermentation of hemp material pretreated with 3% H2O2 resulted...... in the highest overall sugar yield (73.5%), maximum succinic acid titer (21.9gL-1), as well as the highest succinic acid yield (83%). Results obtained clearly demonstrated the impact of different pretreatments on the bioconversion efficiency of industrial hemp into succinic acid....

  19. A new approach to microbial production of gallic acid.

    Science.gov (United States)

    Bajpai, Bhakti; Patil, Shridhar

    2008-10-01

    In a new approach to microbial gallic acid production by Aspergillus fischeri MTCC 150, 40gL(-1) of tannic acid was added in two installments during the bioconversion phase of the process (25gL(-1) and 15gL(-1) at 32 and 44h respectively). The optimum parameters for the bioconversion phase were found to be temperature: 35°C, pH: slightly acidic (3.3-3.5), aeration: nil and agitation: 250 rpm. A maximum of 71.4% conversion was obtained after 71h fermentation with 83.3% product recovery. The yield was 7.35 g of gallic acid per g of biomass accumulated and the fermenter productivity was 0.56 g of gallic acid produced per liter of medium per hour.

  20. Final Scientific/Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Yanna

    2017-12-20

    To increase our understanding of coal biogasification and move this technology closer toward field scale demonstration, we have thoroughly investigated coal bioconversion both ex situ and in situ. Specifically, we have screened a total of 12 parameters and identified those that exert statistically positive influence on coal biogasification. Based on these evaluations, a recipe for a nutrient solution was developed. With the addition of this nutrient solution, methane yield from Illinois coal was enhanced dramatically. In addition, we have demonstrated that coal bioconversion can be sustained over a long period of time as long as suitable conditions were maintained. Furthermore, biogasification of coal was tested under pressure simulating in situ conditions. Surprisingly, pressure was found to have no negative effects on microbial activities. Thus, the same recipe developed for ex situ may be used in situ as well.

  1. Adsorption and mechanism of cellulase enzymes onto lignin isolated from corn stover pretreated with liquid hot water

    OpenAIRE

    Lu, Xianqin; Zheng, Xiaoju; Li, Xuezhi; Zhao, Jian

    2016-01-01

    Background In the bioconversion of lignocellulosic substrates, the adsorption behavior of cellulase onto lignin has a negative effect on enzymatic hydrolysis of cellulose, decreasing glucose production during enzymatic hydrolysis, thus decreasing the yield of fermentation and the production of useful products. Understanding the interaction between lignin and cellulase is necessary to optimize the components of cellulase mixture, genetically engineer high-efficiency cellulase, and reduce cost ...

  2. Cascade catalysis in membranes with enzyme immobilization for multienzymatic conversion of CO2 to methanol

    DEFF Research Database (Denmark)

    Luo, Jianquan; Meyer, Anne S.; Mateiu, Ramona Valentina

    2015-01-01

    .e. by directing membrane fouling formation), without any addition of organic solvent. Such coimmobilization and sequential immobilization systems were examined for the production of methanol from CO2 with formate dehydrogenase (FDH), formaldehyde dehydrogenase (FaldDH) and alcohol dehydrogenase (ADH). Enzyme...... for multi-enzymatic cascade systems, but also reveals the reaction bottleneck and provides possible solutions for the bioconversion of CO2 to methanol....

  3. Use of Growing Cells of Pseudomonas aeruginosa for Synthesis of the Natural Vanillin via Conversion of Isoeugenol

    OpenAIRE

    Ashengroph, Morahem; Nahvi, Iraj; Zarkesh-Esfahani, Hamid; Momenbeik, Fariborz

    2011-01-01

    The great demand of people for consumption of natural additives resulted in producing natural vanillin. There are plant sources and chemical procedures for vanillin production but microbial bioconversions are being sought as a suitable alternative. In the present work, the ability to produce vanillin from isoeugenol was screened using growing cultures of various bacteria. Among the 56 strains of bacteria isolated from the soil environments of Iran, a Gram-negative rod designated as strain ISP...

  4. Application of Taguchi Design and Response Surface Methodology for Improving Conversion of Isoeugenol into Vanillin by Resting Cells of Psychrobacter sp. CSW4

    OpenAIRE

    Ashengroph, Morahem; Nahvi, Iraj; Amini, Jahanshir

    2013-01-01

    For all industrial processes, modelling, optimisation and control are the keys to enhance productivity and ensure product quality. In the current study, the optimization of process parameters for improving the conversion of isoeugenol to vanillin by Psychrobacter sp. CSW4 was investigated by means of Taguchi approach and Box-Behnken statistical design under resting cell conditions. Taguchi design was employed for screening the significant variables in the bioconversion medium. Sequentially, B...

  5. Enzymatic Biosynthesis of Novel Resveratrol Glucoside and Glycoside Derivatives

    OpenAIRE

    Pandey, Ramesh Prasad; Parajuli, Prakash; Shin, Ju Yong; Lee, Jisun; Lee, Seul; Hong, Young-Soo; Park, Yong Il; Kim, Joong Su; Sohng, Jae Kyung

    2014-01-01

    A UDP glucosyltransferase from Bacillus licheniformis was overexpressed, purified, and incubated with nucleotide diphosphate (NDP) d- and l-sugars to produce glucose, galactose, 2-deoxyglucose, viosamine, rhamnose, and fucose sugar-conjugated resveratrol glycosides. Significantly higher (90%) bioconversion of resveratrol was achieved with α-d-glucose as the sugar donor to produce four different glucosides of resveratrol: resveratrol 3-O-β-d-glucoside, resveratrol 4′-O-β-d-glucoside, resveratr...

  6. Co-production of hydrogen and ethanol by Escherichia coli SS1 and its recombinant

    Directory of Open Access Journals (Sweden)

    Chiu-Shyan Soo

    2017-11-01

    Conclusions: HybC could improve glycerol consumption rate and ethanol productivity of E. coli despite lower hydrogen and ethanol yields. Higher glycerol consumption rate of recombinant hybC could be an advantage for bioconversion of glycerol into biofuels. This study could serve as a useful guidance for dissecting the role of hydrogenase in glycerol metabolism and future development of effective strain for biofuels production.

  7. Biogas: fuel of the future

    Energy Technology Data Exchange (ETDEWEB)

    Da Silva, E J

    1980-01-01

    As the energy crisis worsens, bioconversion of organic residue has become increasingly attractive in recent years. There are thousands of biogas plants in developing countries (not including China) and more programs are being launched. Because biogas is conveniently renewable, the author argues that it has a vital role to play, especially as a future source of energy for both developed and developing countries. The operation of a typical biogas plant is described.

  8. Biomethane digestate from horse manure, a new waste usable in compost for growing the button mushroom , Agaricus bisporus ?

    OpenAIRE

    Savoie, Jean-Michel; Vedier, R.; Blanc, Frederic; Minvielle, Nathalie; Rousseaut, T.; Delgenès, Jean-Philippe

    2011-01-01

    Mushroom cultivation is a direct utilization of their ecological role of organic matter degradation in the bioconversion of solid wastes generated from industry and agriculture into edible biomass, which could also be regarded as a functional food or as a source of drugs and pharmaceuticals. Significant changes are expected in the integrated management of wastes streams in the future due to the use of plant biomass for biofuel and energy production and other non-food crops. On the one ...

  9. Cellulase Production by Bacteria: A Review

    OpenAIRE

    Sadhu Sangrila; Maiti Tushar Kanti

    2013-01-01

    Cellulose is an abundant natural biopolymer on earth and most dominating Agricultural waste. This cellulosic biomass is a renewable and abundant resource with great potential for bioconversion to value-added bioproducts. It can be degraded by cellulase produced by cellulolytic bacteria. This enzyme has various industrial applications and now considered as major group of industrial enzyme. The review discusses application of cellulase, classification of cellulase, quantification...

  10. Advances in energy and environment. Vol. 2: Air quality, water quality

    International Nuclear Information System (INIS)

    El-Sharkawy, A.L.; Kummler, R.H.

    1996-01-01

    The 5th conference of energy and environment was held on 3-6 June 1996 in Cairo. The specialists discussed the effects of advances in energy and environment. The applications of solar energy, heat transfer, thermal application, storage and bio-conversion, fuels, energy and development. This second volume covers papers presented on the subjects air pollution, environmental protection, solid and hazardous wastes, water and wastewater treatment. tabs., figs

  11. Evaluation of Diclofenac Prodrugs for Enhancing Transdermal Delivery

    OpenAIRE

    Lobo, Shabbir; Li, Henan; Farhan, Nashid; Yan, Guang

    2013-01-01

    The purpose of this study was to evaluate the approach of using diclofenac acid (DA) prodrugs for enhancing transdermal delivery. Methanol diclofenac ester (MD), ethylene glycol diclofenac ester (ED), glycerol diclofenac ester (GD), and 1,3-propylene glycol diclofenac ester (PD) were synthesized and evaluated for their physicochemical properties such as solubilities, octanol/water partition coefficients, stratum corneum/water partition coefficients, hydrolysis rates, and bioconversion rates. ...

  12. Selection for high muscle fat in rainbow trout induces potentially higher chylomicron synthesis and PUFA biosynthesis in the intestine.

    Science.gov (United States)

    Kamalam, Biju Sam; Panserat, Stephane; Aguirre, Peyo; Geurden, Inge; Fontagné-Dicharry, Stéphanie; Médale, Françoise

    2013-02-01

    Two lines of rainbow trout divergently selected for muscle fat content, fat line (F) and lean line (L) were used to investigate the effect of genetic selection on digestion, intestinal nutrient transport and fatty acid bioconversion, in relation to dietary starch intake. This study involved a digestibility trial for 2 weeks using Cr(2)O(3) as inert marker, followed by a feeding trial for 4 weeks. For the entire duration, juvenile trout from the two lines were fed diets with or without gelatinized starch. Blood, pyloric ceca, midgut and hindgut were sampled at 24 h after the last meal. Transcripts of the proteins involved in nutrient transport and fatty acid bioconversion were abundant in the proximal intestine. GLUT2 transcripts were slightly higher in the F line ceca than in the L line. Dietary starch intake did not enhance the transcription of intestinal glucose transporters, SGLT1 and GLUT2; but it was associated with the higher expression of ApoA1 and PepT1 in the midgut. Significantly, the F line exhibited higher intestinal mRNA levels of MTP, ApoA4, Elovl2, Elovl5 and D6D than the L line, linked to chylomicron assembly and fatty acid bioconversion. Apparent digestibility coefficients of protein, lipid and starch were high in both lines, but not significantly different between them. In conclusion, we found a higher potential of chylomicron synthesis and fatty acid bioconversion in the intestine of F line, but no adaptive transcriptional response of glucose transporters to dietary starch and no genotypic differences in nutrient digestibility. Copyright © 2012 Elsevier Inc. All rights reserved.

  13. Direct conversion of straw to ethanol by Fusarium oxysporum: effect of cellulose crystallinity

    Energy Technology Data Exchange (ETDEWEB)

    Christakopoulos, P.; Koullas, D.P.; Kekos, D.; Koukios, E.G.; Macris, B.J. (Ethnikon Metsovion Polytechneion, Athens (Greece))

    1991-03-01

    Wheat straw was successfully fermented to ethanol by Fusarium oxysporum F3 in a one-step process. Cellulose crystallinity was found to be a major factor in the bioconversion process. Ethanol yields increased linearly with decreasing crystallinity index. Approximately 80% of straw carbohydrates were converted directly to ethanol with a yield of 0.28 g ethanol/g{sup -1} of straw when the crystallinity index was reduced to 23.6%. (author).

  14. Xylitol Production from Eucalyptus Wood Hydrolysates in Low-Cost Fermentation Media

    Directory of Open Access Journals (Sweden)

    José Diz

    2002-01-01

    Full Text Available Several aspects concerning the bioconversion of xylose-containing hydrolysates (obtained from Eucalyptus wood into xylitol were assessed. Debaryomyces hansenii yeast strains were adapted to fermentation media (obtained either by prehydrolysis or autohydrolysis- posthydrolysis of wood supplemented with low-cost nutrients. Media containing up to 80 g/L xylose were efficiently fermented when the hydrolysates were detoxified by charcoal adsorption and supplemented with corn steep liquor.

  15. Structural insight into catalytic mechanism of PET hydrolase

    OpenAIRE

    Han, Xu; Liu, Weidong; Huang, Jian-Wen; Ma, Jiantao; Zheng, Yingying; Ko, Tzu-Ping; Xu, Limin; Cheng, Ya-Shan; Chen, Chun-Chi; Guo, Rey-Ting

    2017-01-01

    PET hydrolase (PETase), which hydrolyzes polyethylene terephthalate (PET) into soluble building blocks, provides an attractive avenue for the bioconversion of plastics. Here we present the structures of a novel PETase from the PET-consuming microbe Ideonella sakaiensis in complex with substrate and product analogs. Through structural analyses, mutagenesis, and activity measurements, a substrate-binding mode is proposed, and several features critical for catalysis are elucidated.

  16. Structural insight into catalytic mechanism of PET hydrolase.

    Science.gov (United States)

    Han, Xu; Liu, Weidong; Huang, Jian-Wen; Ma, Jiantao; Zheng, Yingying; Ko, Tzu-Ping; Xu, Limin; Cheng, Ya-Shan; Chen, Chun-Chi; Guo, Rey-Ting

    2017-12-13

    PET hydrolase (PETase), which hydrolyzes polyethylene terephthalate (PET) into soluble building blocks, provides an attractive avenue for the bioconversion of plastics. Here we present the structures of a novel PETase from the PET-consuming microbe Ideonella sakaiensis in complex with substrate and product analogs. Through structural analyses, mutagenesis, and activity measurements, a substrate-binding mode is proposed, and several features critical for catalysis are elucidated.

  17. Research and development in alternative energy sources

    International Nuclear Information System (INIS)

    Lamptey, J.; Moo-Young, M.; Sullivan, H.F.

    1990-01-01

    This paper comprehensively discusses the various bioconversion and thermochemical processes. It recommends that the most urgent research and development issues should relate to direct microbial conversion systems for starch and cellulosic material and to basic biomass combustion rates and mechanisms. An overview of some of the major renewable energy resources and conversion technologies along with the potentials and problems associated with these are also presented.(author). 235 refs., 2 tabs

  18. Assessment of the genotoxicity of Cu and Zn in raw and anaerobically digested slurry with the Vicia faba micronucleus test

    OpenAIRE

    Marcato, Claire-Emmanuelle; Pinelli, Eric; Pourrut, Bertrand; Silvestre, Jérôme; Guiresse, Agnès Maritchù

    2009-01-01

    Genotoxicity of Cu and Zn was assessed by use of the micronucleus (MN) test on Vicia faba roots. Plants were exposed to various leachates of rawand anaerobically digested pig slurry, with maximum total concentrations of 200MCu and 600MZn. The results indicated stabilisation of the organic matter during anaerobic digestion of the slurry and bioconversion of some phytotoxic organic compounds (e.g. phenols or p-cresol), but did not showa relationship between Cu and Zn concentrations and MN fr...

  19. Evaluation of Packed-Bed Reactor and Continuous Stirred Tank Reactor for the Production of Colchicine Derivatives

    OpenAIRE

    Dubey, Kashyap Kumar; Kumar, Dhirendra; Kumar, Punit; Haque, Shafiul; Jawed, Arshad

    2013-01-01

    Bioconversion of colchicine into its pharmacologically active derivative 3-demethylated colchicine (3-DMC) mediated by P450BM3 enzyme is an economic and promising strategy for the production of this inexpensive and potent anticancer drug. Continuous stirred tank reactor (CSTR) and packed-bed reactor (PBR) of 3 L and 2 L total volumes were compared for the production of 3-demethylated colchicine (3-DMC) a colchicine derivative using Bacillus megaterium MTCC*420 under aerobic conditions. Statis...

  20. Phycoremediation of industrial wastewater containing azo compounds

    OpenAIRE

    Parin D. Shah; Dipti Galani; M S. Rao

    2000-01-01

    This paper summarizes the state-of-the-art biological wastewater treatment technique that uses eukaryotic microalgae as well as several prokaryotic photosynthetic cyanobacteria. Micro algae are known to remove dyes by bioadsorption (sorption of dye molecules over the surface of algal cells), biodegradation and bioconversion (diffusion of dye molecules into the algal cells and subsequent conversion). This paper mainly focuses on biodegradation abilities of microalgae for t...

  1. Rekombinante Biosynthese von p-Cumarylalkohol in E. coli

    OpenAIRE

    Jansen, Frank

    2011-01-01

    The increasingly scarce availability of fossil raw materials calls for the development of new strategies to ensure the sustainable supply with energy and components for synthesis. Energy and mass bioconversion processes of renewable raw materials can contribute in minimizing the dependence on fossil raw materials and close the gap in energy supply. Currently though, renewable raw materials cannot completely replace fossil raw materials. The emphasis lies more on the concept of using renewable...

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

    Energy Technology Data Exchange (ETDEWEB)

    Davis, R.; Tao, L.; Tan, E. C. D.; Biddy, M. J.; Beckham, G. T.; Scarlata, C.; Jacobson, J.; Cafferty, K.; Ross, J.; Lukas, J.; Knorr, D.; Schoen, P.

    2013-10-01

    This report describes one potential conversion process to hydrocarbon products by way of biological conversion of lingnocellulosic-dervied sugars. The process design converts biomass to a hydrocarbon intermediate, a free fatty acid, using dilute-acid pretreatement, enzymatic saccharification, and bioconversion. Ancillary areas--feed handling, hydrolysate conditioning, product recovery and upgrading (hydrotreating) to a final blendstock material, wastewater treatment, lignin combusion, and utilities--are also included in the design.

  3. Application of biotechnology to fossil fuels explored

    Energy Technology Data Exchange (ETDEWEB)

    Haggin, J

    1989-02-13

    A review is presented of the December 1988 symposium on coal, oil and gas biotechnology held in New Orleans, organised by the Institute of Gas Technology. Papers discussed include: opportunities for R D in desulfurization, coal gasification and environmental cleanup; an assessment of the economic constraints that new energy biotechnology must overcome; biotechnology research at EPRI; microbial conversion of coal; bioconversion of low rank coal; and bioremediation of ground containing PAHs. 2 figs.

  4. Potential of Rhodococcus strains for biotechnological vanillin production from ferulic acid and eugenol.

    Science.gov (United States)

    Plaggenborg, Rainer; Overhage, Jörg; Loos, Andrea; Archer, John A C; Lessard, Philip; Sinskey, Anthony J; Steinbüchel, Alexander; Priefert, Horst

    2006-10-01

    The potential of two Rhodococcus strains for biotechnological vanillin production from ferulic acid and eugenol was investigated. Genome sequence data of Rhodococcus sp. I24 suggested a coenzyme A-dependent, non-beta-oxidative pathway for ferulic acid bioconversion, which involves feruloyl-CoA synthetase (Fcs), enoyl-CoA hydratase/aldolase (Ech), and vanillin dehydrogenase (Vdh). This pathway was proven for Rhodococcus opacus PD630 by physiological characterization of knockout mutants. However, expression and functional characterization of corresponding structural genes from I24 suggested that degradation of ferulic acid in this strain proceeds via a beta-oxidative pathway. The vanillin precursor eugenol facilitated growth of I24 but not of PD630. Coniferyl aldehyde was an intermediate of eugenol degradation by I24. Since the genome sequence of I24 is devoid of eugenol hydroxylase homologous genes (ehyAB), eugenol bioconversion is most probably initiated by a new step in this bacterium. To establish eugenol bioconversion in PD630, the vanillyl alcohol oxidase gene (vaoA) from Penicillium simplicissimum CBS 170.90 was expressed in PD630 together with coniferyl alcohol dehydrogenase (calA) and coniferyl aldehyde dehydrogenase (calB) genes from Pseudomonas sp. HR199. The recombinant strain converted eugenol to ferulic acid. The obtained data suggest that genetically engineered strains of I24 and PD630 are suitable candidates for vanillin production from eugenol.

  5. Novel Halomonas sp. B15 isolated from Larnaca Salt Lake in Cyprus that generates vanillin and vanillic acid from ferulic acid.

    Science.gov (United States)

    Vyrides, Ioannis; Agathangelou, Maria; Dimitriou, Rodothea; Souroullas, Konstantinos; Salamex, Anastasia; Ioannou, Aristostodimos; Koutinas, Michalis

    2015-08-01

    Vanillin is a high value added product with many applications in the food, fragrance and pharmaceutical industries. A natural and low-cost method to produce vanillin is by microbial bioconversions through ferulic acid. Until now, limited microorganisms have been found capable of bioconverting ferulic acid to vanillin at high yield. This study aimed to screen halotolerant strains of bacteria from Larnaca Salt Lake which generate vanillin and vanillic acid from ferulic acid. From a total of 50 halotolenant/halophilic strains 8 grew in 1 g/L ferulic acid and only 1 Halomonas sp. B15 and 3 Halomonas elognata strains were capable of bioconverting ferulic acid to vanillic acid at 100 g NaCl/L. The highest vanillic acid (365 mg/L) at these conditions generated by Halomonas sp. B15 which corresponds to ferulic acid bioconversion yield of 36.5%. Using the resting cell technique with an initial ferulic acid concentration of 0.5 g/L at low salinity, the highest production of vanillin (245 mg/L) took place after 48 h, corresponding to a bioconversion yield of 49%. This is the first reported Halomonas sp. with high yield of vanillin production from ferulic acid at low salinity.

  6. Pilot scale repeated fed-batch fermentation processes of the wine yeast Dekkera bruxellensis for mass production of resveratrol from Polygonum cuspidatum.

    Science.gov (United States)

    Kuo, Hsiao-Ping; Wang, Reuben; Lin, Yi-Sheng; Lai, Jinn-Tsyy; Lo, Yi-Chen; Huang, Shyue-Tsong

    2017-11-01

    Resveratrol has long been used as an ingredient in functional foods. Currently, Polygonum cuspidatum extract is the greatest natural source for resveratrol because of high concentrations of glycosidic-linked resveratrol. Thus, developing a cost-effective procedure to hydrolyze glucoside could substantially enhance resveratrol production from P. cuspidatum. This study selected Dekkera bruxellensis from several microorganisms based on its bioconversion and enzyme-specific activities. We demonstrated that the cells could be reused at least nine times while maintaining an average of 180.67U/L β-glucosidase activity. The average resveratrol bioconversion efficiency within five rounds of repeated usage was 108.77±0.88%. This process worked effectively when the volume was increased to 1200L, a volume at which approximately 35mgL -1 h -1 resveratrol per round was produced. This repeated fed-batch bioconversion process for resveratrol production is comparable to enzyme or cell immobilization strategies in terms of reusing cycles, but without incurring additional costs for immobilization. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Reverse membrane bioreactor: Introduction to a new technology for biofuel production.

    Science.gov (United States)

    Mahboubi, Amir; Ylitervo, Päivi; Doyen, Wim; De Wever, Heleen; Taherzadeh, Mohammad J

    2016-01-01

    The novel concept of reverse membrane bioreactors (rMBR) introduced in this review is a new membrane-assisted cell retention technique benefiting from the advantageous properties of both conventional MBRs and cell encapsulation techniques to tackle issues in bioconversion and fermentation of complex feeds. The rMBR applies high local cell density and membrane separation of cell/feed to the conventional immersed membrane bioreactor (iMBR) set up. Moreover, this new membrane configuration functions on basis of concentration-driven diffusion rather than pressure-driven convection previously used in conventional MBRs. These new features bring along the exceptional ability of rMBRs in aiding complex bioconversion and fermentation feeds containing high concentrations of inhibitory compounds, a variety of sugar sources and high suspended solid content. In the current review, the similarities and differences between the rMBR and conventional MBRs and cell encapsulation regarding advantages, disadvantages, principles and applications for biofuel production are presented and compared. Moreover, the potential of rMBRs in bioconversion of specific complex substrates of interest such as lignocellulosic hydrolysate is thoroughly studied. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  8. Comparative LCA of Alternative Scenarios for Waste Treatment: The Case of Food Waste Production by the Mass-Retail Sector

    Directory of Open Access Journals (Sweden)

    Giovanni Mondello

    2017-05-01

    Full Text Available Food waste is one of the most important issues taken into account by the European Union due to its negative environmental, economic and social impacts. The treatment of food waste through recycling processes represents a solution for food waste minimisation. Concerning, in particular, the retail sector, it is necessary to define strategies for retail-oriented sustainable food waste management. The aim of this study is to compare the potential environmental impacts related to five scenarios (landfill, incineration, composting, anaerobic digestion and bioconversion through insects for the disposal/treatment of food waste produced by a mass retail company operating in Messina (Italy through the application of the Life Cycle Assessment method, in order to find the best treatment solution. Results based on the treatment of a functional unit of 1 tonne of food waste show that the bioconversion scenario represents the most preferable solution considering all of the impact categories analysed through the CML 2 baseline 2000 method, except for Global Warming, for which higher environmental performances are connected to the anaerobic digestion scenario. The incineration and the bioconversion scenarios show the highest environmental benefits when the production of alternative energy sources and valuable materials is evaluated through the inclusion of the avoided productions in the analysis.

  9. Analysis, pretreatment and enzymatic saccharification of different fractions of Scots pine

    Science.gov (United States)

    2014-01-01

    Background Forestry residues consisting of softwood are a major lignocellulosic resource for production of liquid biofuels. Scots pine, a commercially important forest tree, was fractionated into seven fractions of chips: juvenile heartwood, mature heartwood, juvenile sapwood, mature sapwood, bark, top parts, and knotwood. The different fractions were characterized analytically with regard to chemical composition and susceptibility to dilute-acid pretreatment and enzymatic saccharification. Results All fractions were characterized by a high glucan content (38-43%) and a high content of other carbohydrates (11-14% mannan, 2-4% galactan) that generate easily convertible hexose sugars, and by a low content of inorganic material (0.2-0.9% ash). The lignin content was relatively uniform (27-32%) and the syringyl-guaiacyl ratio of the different fractions were within the range 0.021-0.025. The knotwood had a high content of extractives (9%) compared to the other fractions. The effects of pretreatment and enzymatic saccharification were relatively similar, but without pretreatment the bark fraction was considerably more susceptible to enzymatic saccharification. Conclusions Since sawn timber is a main product from softwood species such as Scots pine, it is an important issue whether different parts of the tree are equally suitable for bioconversion processes. The investigation shows that bioconversion of Scots pine is facilitated by that most of the different fractions exhibit relatively similar properties with regard to chemical composition and susceptibility to techniques used for bioconversion of woody biomass. PMID:24641769

  10. Preliminary Economics for Hydrocarbon Fuel Production from Cellulosic Sugars

    Energy Technology Data Exchange (ETDEWEB)

    Collett, James R.; Meyer, Pimphan A.; Jones, Susanne B.

    2014-05-18

    Biorefinery process and economic models built in CHEMCAD and a preliminary, genome-scale metabolic model for the oleaginous yeast Lipomyces starkeyi were used to simulate the bioconversion of corn stover to lipids, and the upgrading of these hydrocarbon precursors to diesel and jet fuel. The metabolic model was based on the recently released genome sequence for L. starkeyi and on metabolic pathway information from the literature. The process model was based on bioconversion, lipid extraction, and lipid oil upgrading data found in literature, on new laboratory experimental data, and on yield predictions from the preliminary L. starkeyi metabolic model. The current plant gate production cost for a distillate-range hydrocarbon fuel was estimated by the process model Base Case to be $9.5/gallon ($9.0 /gallon of gasoline equivalent) with assumptions of 2011$, 10% internal return on investment, and 2205 ton/day dry feed rate. Opportunities for reducing the cost to below $5.0/gallon, such as improving bioconversion lipid yield and hydrogenation catalyst selectivity, are presented in a Target Case. The process and economic models developed for this work will be updated in 2014 with new experimental data and predictions from a refined metabolic network model for L. starkeyi. Attaining a production cost of $3.0/gallon will require finding higher value uses for lignin other than power generation, such as conversion to additional fuel or to a co-product.

  11. Substrate Specificity and Enzyme Recycling Using Chitosan Immobilized Laccase

    Directory of Open Access Journals (Sweden)

    Everton Skoronski

    2014-10-01

    Full Text Available The immobilization of laccase (Aspergillus sp. on chitosan by cross-linking and its application in bioconversion of phenolic compounds in batch reactors were studied. Investigation was performed using laccase immobilized via chemical cross-linking due to the higher enzymatic operational stability of this method as compared to immobilization via physical adsorption. To assess the influence of different substrate functional groups on the enzyme’s catalytic efficiency, substrate specificity was investigated using chitosan-immobilized laccase and eighteen different phenol derivatives. It was observed that 4-nitrophenol was not oxidized, while 2,5-xylenol, 2,6-xylenol, 2,3,5-trimethylphenol, syringaldazine, 2,6-dimetoxyphenol and ethylphenol showed reaction yields up 90% at 40 °C. The kinetic of process, enzyme recyclability and operational stability were studied. In batch reactors, it was not possible to reuse the enzyme when it was applied to syringaldazne bioconversion. However, when the enzyme was applied to bioconversion of 2,6-DMP, the activity was stable for eight reaction batches.

  12. Selective component degradation of oil palm empty fruit bunches (OPEFB) using high-pressure steam

    International Nuclear Information System (INIS)

    Baharuddin, Azhari Samsu; Sulaiman, Alawi; Kim, Dong Hee; Mokhtar, Mohd Noriznan; Hassan, Mohd Ali; Wakisaka, Minato; Shirai, Yoshihito; Nishida, Haruo

    2013-01-01

    In order to accelerate the bioconversion process of press-shredded empty fruit bunches (EFB), the effect of high-pressure steam pre-treatment (HPST) in degrading the lignocellulosic structure was investigated. HPST was carried out under various sets of temperature/pressure conditions such as 170/0.82, 190/1.32, 210/2.03, and 230 °C/3.00 MPa. It was noted that after HPST, the surface texture, color, and mechanical properties of the treated EFB had obviously altered. Scanning electron micrographs of the treated EFB exhibited effective surface erosion that had occurred along the structure. Moreover, the Fourier transform infrared and thermogravimetric analyses showed the removal of silica bodies and hemicellulose ingredients. X-ray diffraction profiles of the treated EFB indicated significant increases in crystallinity. These results reveal that HPST is an effective pre-treatment method for altering the physicochemical properties of the EFB and enhancing its biodegradability characteristics for the bioconversion process. -- Highlights: ► Bioconversion of empty fruit bunches (EFB) was accelerated by high-pressure steam pre-treatment. ► Scanning electron micrographs exhibited surface erosion as well as composting over 20 days. ► FT-IR and TG data showed the selective removal of silica bodies and hemicellulose ingredient. ► X-ray diffraction profiles of the treated EFB indicated significant increases in crystallinity

  13. Enhanced biocatalytic production of L-cysteine by Pseudomonas sp. B-3 with in situ product removal using ion-exchange resin.

    Science.gov (United States)

    Wang, Pu; He, Jun-Yao; Yin, Jiang-Feng

    2015-03-01

    Bioconversion of DL-2-amino-Δ(2)-thiazoline-4-carboxylic acid (DL-ATC) catalyzed by whole cells of Pseudomonas sp. was successfully applied for the production of L-cysteine. It was found, however, like most whole-cell biocatalytic processes, the accumulated L-cysteine produced obvious inhibition to the activity of biocatalyst and reduced the yield. To improve L-cysteine productivity, an anion exchange-based in situ product removal (ISPR) approach was developed. Several anion-exchange resins were tested to select a suitable adsorbent used in the bioconversion of DL-ATC for the in situ removal of L-cysteine. The strong basic anion-exchange resin 201 × 7 exhibited the highest adsorption capacity for L-cysteine and low adsorption for DL-ATC, which is a favorable option. With in situ addition of 60 g L(-1) resin 201 × 7, the product inhibition can be reduced significantly and 200 mmol L(-1) of DL-ATC was converted to L-cysteine with 90.4 % of yield and 28.6 mmol L(-1 )h(-1) of volumetric productivity. Compared to the bioconversion without the addition of resin, the volumetric productivity of L-cysteine was improved by 2.27-fold using ISPR method.

  14. Microplate-Based Evaluation of the Sugar Yield from Giant Reed, Giant Miscanthus and Switchgrass after Mild Chemical Pre-Treatments and Hydrolysis with Tailored Trichoderma Enzymatic Blends.

    Science.gov (United States)

    Cianchetta, Stefano; Bregoli, Luca; Galletti, Stefania

    2017-11-01

    Giant reed, miscanthus, and switchgrass are considered prominent lignocellulosic feedstocks to obtain fermentable sugars for biofuel production. The bioconversion into sugars requires a delignifying pre-treatment step followed by hydrolysis with cellulase and other accessory enzymes like xylanase, especially in the case of alkali pre-treatments, which retain the hemicellulose fraction. Blends richer in accessory enzymes than commercial mix can be obtained growing fungi on feedstock-based substrates, thus ten selected Trichoderma isolates, including the hypercellulolytic strain Trichoderma reesei Rut-C30, were grown on giant reed, miscanthus, or switchgrass-based substrates. The produced enzymes were used to saccharify the corresponding feedstocks, compared to a commercial enzymatic mix (6 FPU/g). Feedstocks were acid (H 2 SO 4 0.2-2%, w/v) or alkali (NaOH 0.02-0.2%, w/v) pre-treated. A microplate-based approach was chosen for most of the experimental steps due to the large number of samples. The highest bioconversion was generally obtained with Trichoderma harzianum Or4/99 enzymes (78, 89, and 94% final sugar yields at 48 h for giant reed, miscanthus, and switchgrass, respectively), with significant increases compared to the commercial mix, especially with alkaline pre-treatments. The differences in bioconversion yields were only partially caused by xylanases (maximum R 2  = 0.5), indicating a role for other accessory enzymes.

  15. Direct conversion of starch to ethanol using recombınant Saccharomyces cerevisiae containing glucoamylase gene

    Science.gov (United States)

    Purkan, P.; Baktir, A.; Puspaningsih, N. N. T.; Ni'mah, M.

    2017-09-01

    Saccharomyces cerevisiae is known for its high fermentative capacity, high ethanol yield and its high ethanol tolerance. The yeast is inability converting starch (relatively inexpensive substrate) into biofuel ethanol. Insertion of glucoamylase gene in yeast cell of Saccharomyces cerevisiae had been done to increase the yeast function in ethanol fermentation from starch. Transformation of yeast of S. cerevisiae with recombinant plasmid yEP-GLO1 carrying gene encoding glucoamylase (GLO1) produced the recombinant yeast which enable to degrade starch. Optimizing of bioconversion process of starch into ethanol by the yeast of recombinant Saccharomyces cerevisiae [yEP-GLO1] had been also done. Starch concentration which could be digested by recombinant yeast of S. cerevisiae [yEP-GLO1] was 10% (w/v). Bioconversion of starch having concentration 10% (b/v) using recombinant yeast of S. cerevisiae BY5207 [yEP-GLO1] could result ethanol as 20% (v/v) to alcoholmeter and 19,5% (v/v) to gas of chromatography. Otherwise, using recombinant yeast S. cerevisiae S. cerevisiae AS3324 [yEP-GLO1] resulted ethanol as 17% (v/v) to alcoholmeter and 17,5% (v/v) to gas of chromatography. The highest ethanol in starch bioconversion using both recombinant yeasts BY5207 and AS3324 could be resulted on 144 hours of fermentation time as well as in pH 5.

  16. Utilisation potential of products of microbial coal liquefaction. Final report; Verwertungspotential der Produkte der mikrobiellen Kohleverfluessigung. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Koepsel, R.; Schmiers, H.; Grosse, S.; Weber, A.

    2002-07-01

    Ever since the discovery in the 1980s that microorganisms are capable of converting coal into soluble products research groups all over the world have been exploring the bioconversion of coal. It was at an advance stage of the present integrated project, which initially only involved microbiology research groups, that the need for a chemical working group with knowledge and experience in the area of coal chemistry and structural analysis of coal was recognised. The task of the chemical working group was to provide knowledge on the chemical nature of bioconversion products and the chemical processes of coal bioconversion. This involved identifying structural changes occurring in the feed coal as well as in its constituent humic acids and macromolecular matrix as a result of the activity of coal degrading microorganisms. [German] Nachdem Anfang der achtziger Jahre entdeckt wurde, dass sich Kohlen durch Mikroorganismen in loesliche Produkte ueberfuehren lassen, agieren weltweit Forschergruppen auf dem Gebiet der Biokonversion von Kohle. In einem fortgeschrittenen Bearbeitungsstadium des Verbundprojektes, an dem zunaechst nur mikrobiologische Arbeitsgruppen beteiligt waren, wurde die Notwendigkeit erkannt, eine chemische Arbeitsgruppe mit Kenntnissen und Erfahrungen auf den Gebieten der Kohlechemie und der Strukturanalytik von Kohlen zu integrieren. Aufgabenstellung der chemischen Arbeitsgruppe war und ist es, Erkenntnisse ueber die chemische Natur der Biokonversionsprodukte und die chemischen Ablaeufe der mikrobiellen Kohlekonversion bereitstellen. Die Aufgabenstellung umfasst die Aufklaerung der strukturellen Veraenderung der Einsatzkohle sowie ihrer Komponenten Huminsaeuren und makromolekulare Matrix durch die Einwirkung kohleabbauender Mikroorganismen. (orig.)

  17. Microbial transformation of hydroxy metabolites of 1-oxohexyl derivatives of theobromine by Cunninghamella echinulata NRRL 1384.

    Science.gov (United States)

    Pekala, E; Kochan, M; Carnell, A J

    2009-01-01

    The biotransformation of pentoxifylline (PTX), propentofylline (PPT) and their racemic hydroxy metabolites ((+/-)-OHPTX and (+/-)-OHPPT) by using the fungus Cunninghamella echinulata NRRL 1384. A fungus Cunninghamella echinulata NRRL 1384 was used to catalyse the (S)-selective oxidation of the racemic hydroxy metabolites: (+/-)-OHPTX and (+/-)-OHPPT and for reduction of PTX and PPT. The first oxidation step appears to be selective and relatively fast while the second reduction step is slower and more selective with PTX. Modifications involving supplementing the bioconversion with glucose give yields and enantiomeric excess (ee) values similar to those obtained without glucose. The bioconversion of (+/-)-OHPTX gave an (R)-enantiomer (LSF-lisofylline) with a higher enantiopurity (maximum approximately 93% ee) compared to the bioconversion of (+/-)-OHPPT, when the maximum ee value for (R)-OHPPT was recorded at 83%. The conversion of (+/-)-OHPTX and (+/-)-OHPPT using Cunninghamella echinulata can be recognized as a process, which may be recommended as an alternative to the methods used to obtain (R)-OHPTX and (R)-OHPPT.

  18. In-Situ Microbial Conversion of Sequestered Greenhouse Gases

    Energy Technology Data Exchange (ETDEWEB)

    Scott, A R; Mukhopadhyay, M; Balin, D F

    2012-09-06

    The objectives of the project are to use microbiological in situ bioconversion technology to convert sequestered or naturally-occurring greenhouse gases, including carbon dioxide and carbon monoxide, into methane and other useful organic compounds. The key factors affecting coal bioconversion identified in this research include (1) coal properties, (2) thermal maturation and coalification process, (3) microbial population dynamics, (4) hydrodynamics (5) reservoir conditions, and (6) the methodology of getting the nutrients into the coal seams. While nearly all cultures produced methane, we were unable to confirm sustained methane production from the enrichments. We believe that the methane generation may have been derived from readily metabolized organic matter in the coal samples and/or biosoluble organic material in the coal formation water. This raises the intriguing possibility that pretreatment of the coal in the subsurface to bioactivate the coal prior to the injection of microbes and nutrients might be possible. We determined that it would be more cost effective to inject nutrients into coal seams to stimulate indigenous microbes in the coal seams, than to grow microbes in fermentation vats and transport them to the well site. If the coal bioconversion process can be developed on a larger scale, then the cost to generate methane could be less than $1 per Mcf

  19. Application of Taguchi Design and Response Surface Methodology for Improving Conversion of Isoeugenol into Vanillin by Resting Cells of Psychrobacter sp. CSW4.

    Science.gov (United States)

    Ashengroph, Morahem; Nahvi, Iraj; Amini, Jahanshir

    2013-01-01

    For all industrial processes, modelling, optimisation and control are the keys to enhance productivity and ensure product quality. In the current study, the optimization of process parameters for improving the conversion of isoeugenol to vanillin by Psychrobacter sp. CSW4 was investigated by means of Taguchi approach and Box-Behnken statistical design under resting cell conditions. Taguchi design was employed for screening the significant variables in the bioconversion medium. Sequentially, Box-Behnken design experiments under Response Surface Methodology (RSM) was used for further optimization. Four factors (isoeugenol, NaCl, biomass and tween 80 initial concentrations), which have significant effects on vanillin yield, were selected from ten variables by Taguchi experimental design. With the regression coefficient analysis in the Box-Behnken design, a relationship between vanillin production and four significant variables was obtained, and the optimum levels of the four variables were as follows: initial isoeugenol concentration 6.5 g/L, initial tween 80 concentration 0.89 g/L, initial NaCl concentration 113.2 g/L and initial biomass concentration 6.27 g/L. Under these optimized conditions, the maximum predicted concentration of vanillin was 2.25 g/L. These optimized values of the factors were validated in a triplicate shaking flask study and an average of 2.19 g/L for vanillin, which corresponded to a molar yield 36.3%, after a 24 h bioconversion was obtained. The present work is the first one reporting the application of Taguchi design and Response surface methodology for optimizing bioconversion of isoeugenol into vanillin under resting cell conditions.

  20. Valorization of industrial waste and by-product streams via fermentation for the production of chemicals and biopolymers.

    Science.gov (United States)

    Koutinas, Apostolis A; Vlysidis, Anestis; Pleissner, Daniel; Kopsahelis, Nikolaos; Lopez Garcia, Isabel; Kookos, Ioannis K; Papanikolaou, Seraphim; Kwan, Tsz Him; Lin, Carol Sze Ki

    2014-04-21

    The transition from a fossil fuel-based economy to a bio-based economy necessitates the exploitation of synergies, scientific innovations and breakthroughs, and step changes in the infrastructure of chemical industry. Sustainable production of chemicals and biopolymers should be dependent entirely on renewable carbon. White biotechnology could provide the necessary tools for the evolution of microbial bioconversion into a key unit operation in future biorefineries. Waste and by-product streams from existing industrial sectors (e.g., food industry, pulp and paper industry, biodiesel and bioethanol production) could be used as renewable resources for both biorefinery development and production of nutrient-complete fermentation feedstocks. This review focuses on the potential of utilizing waste and by-product streams from current industrial activities for the production of chemicals and biopolymers via microbial bioconversion. The first part of this review presents the current status and prospects on fermentative production of important platform chemicals (i.e., selected C2-C6 metabolic products and single cell oil) and biopolymers (i.e., polyhydroxyalkanoates and bacterial cellulose). In the second part, the qualitative and quantitative characteristics of waste and by-product streams from existing industrial sectors are presented. In the third part, the techno-economic aspects of bioconversion processes are critically reviewed. Four case studies showing the potential of case-specific waste and by-product streams for the production of succinic acid and polyhydroxyalkanoates are presented. It is evident that fermentative production of chemicals and biopolymers via refining of waste and by-product streams is a highly important research area with significant prospects for industrial applications.

  1. Production of raw starch-degrading enzyme by Aspergillus sp. and its use in conversion of inedible wild cassava flour to bioethanol.

    Science.gov (United States)

    Moshi, Anselm P; Hosea, Ken M M; Elisante, Emrode; Mamo, Gashaw; Önnby, Linda; Nges, Ivo Achu

    2016-04-01

    The major bottlenecks in achieving competitive bioethanol fuel are the high cost of feedstock, energy and enzymes employed in pretreatment prior to fermentation. Lignocellulosic biomass has been proposed as an alternative feedstock, but because of its complexity, economic viability is yet to be realized. Therefore, research around non-conventional feedstocks and deployment of bioconversion approaches that downsize the cost of energy and enzymes is justified. In this study, a non-conventional feedstock, inedible wild cassava was used for bioethanol production. Bioconversion of raw starch from the wild cassava to bioethanol at low temperature was investigated using both a co-culture of Aspergillus sp. and Saccharomyces cerevisiae, and a monoculture of the later with enzyme preparation from the former. A newly isolated strain of Aspergillus sp. MZA-3 produced raw starch-degrading enzyme which displayed highest activity of 3.3 U/mL towards raw starch from wild cassava at 50°C, pH 5.5. A co-culture of MZA-3 and S. cerevisiae; and a monoculture of S. cerevisiae and MZA-3 enzyme (both supplemented with glucoamylase) resulted into bioethanol yield (percentage of the theoretical yield) of 91 and 95 at efficiency (percentage) of 84 and 96, respectively. Direct bioconversion of raw starch to bioethanol was achieved at 30°C through the co-culture approach. This could be attractive since it may significantly downsize energy expenses. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  2. Microbiology and physiology of anaerobic fermentation of cellulose. Annual report for 1990, 1992, 1993 and final report

    Energy Technology Data Exchange (ETDEWEB)

    Ljungdahl, L.G.; Wiegel, J.; Peck, H.D. Jr.; Mortenson, L.E.

    1993-08-31

    This report focuses on the bioconversion of cellulose to methane by various anaerobes. The structure and enzymatic activity of cellulosome and polycellulosome was studied in Clostridium thermocellum. The extracellular enzymes involved in the degradation of plant material and the physiology of fermentation was investigated in anaerobic fungi. Enzymes dealing with CO, CO{sub 2}, H{sub 2}, CH{sub 3}OH, as well as electron transport and energy generation coupled to the acetyl-CoA autotrophic pathway was studied in acetogenic clostridia.

  3. Neutrophilic iron-oxidizing bacteria: occurrence and relevance in biological drinking water treatment

    DEFF Research Database (Denmark)

    Gülay, Arda; Musovic, Sanin; Albrechtsen, Hans-Jørgen

    2013-01-01

    Rapid sand filtration (RSF) is an economical way to treat anoxic groundwater around the world. It consists of groundwater aeration followed by passage through a sand filter. The oxidation and removal of ferrous iron, which is commonly found in anoxic groundwaters, is often believed to be a fully...... role of FeOB in iron removal at waterworks using RSF technologies....... physicochemical process. However, persistently low temperatures in RSF across Denmark may negatively affect the kinetics of chemical oxidation. The slower chemical oxidation of ferrous iron may increase the chances for iron bioconversion by neutrophilic iron-oxidizing bacteria (FeOB), which are found naturally...

  4. Proceedings of the international symposium on coal - science, technology, industry, business, environment

    Energy Technology Data Exchange (ETDEWEB)

    Narasimhan, K.S.; Sen, S. [eds.

    1996-12-31

    Papers were presented which covered the areas of coal science, advanced coal preparation, coal utilization, coal chemicals and the environment. These included carbon aromaticity, mineral studies, utilization of low rank coals, bioconversion of methane, swelling of coals, photocatalytic activity, flotation and effects of oxidation, microbial desulfurization, deashing, briquetting, commercial scale conversion of coal to fuels and chemicals, role of coal in iron and steel making, coal-water mixtures, dyes and chemical products, nitrogen oxides emissions and pollution control. 45 papers have been abstracted separately for the IEA Coal Research CD-ROM.

  5. Biotechnological production of vanillin.

    Science.gov (United States)

    Priefert, H; Rabenhorst, J; Steinbüchel, A

    2001-08-01

    Vanillin is one of the most important aromatic flavor compounds used in foods, beverages, perfumes, and pharmaceuticals and is produced on a scale of more than 10 thousand tons per year by the industry through chemical synthesis. Alternative biotechnology-based approaches for the production are based on bioconversion of lignin, phenolic stilbenes, isoeugenol, eugenol, ferulic acid, or aromatic amino acids, and on de novo biosynthesis, applying fungi, bacteria, plant cells, or genetically engineered microorganisms. Here, the different biosynthesis routes involved in biotechnological vanillin production are discussed.

  6. Escherichia coli modular coculture system for resveratrol glucosides production

    DEFF Research Database (Denmark)

    Thuan, Nguyen Huy; Trung, Nguyen Thanh; Cuong, Nguyen Xuan

    2018-01-01

    converting para-coumaric acid into resveratrol and the downstream module expressing glucosyltransferase to convert the resveratrol into its glucosidated forms; polydatin and resveratroloside. Upon optimization of the initial inoculum ratio of two E. coli populations, 92 mg resveratrol glucosides/L (236 µ......M) was produced i.e. achieving 84% bioconversion from 280 µM of p-coumaric acid in 60 h by 3 L fed batch fermentor. This is the report of applying coculture system to produce resveratrol glucosides by expressing the aglycone formation pathway and sugar dependent pathway into two different cells....

  7. The acid-tolerant L-arabinose isomerase from the mesophilic Shewanella sp. ANA-3 is highly active at low temperatures

    Science.gov (United States)

    2011-01-01

    Background L-arabinose isomerases catalyse the isomerization of L-arabinose into L-ribulose at insight biological systems. At industrial scale of this enzyme is used for the bioconversion of D-galactose into D-tagatose which has many applications in pharmaceutical and agro-food industries. The isomerization reaction is thermodynamically equilibrated, and therefore the bioconversion rates is shifted towards tagatose when the temperature is increased. Moreover, to prevent secondary reactions it will be of interest to operate at low pH. The profitability of this D-tagatose production process is mainly related to the use of lactose as cheaper raw material. In many dairy products it will be interesting to produce D-tagatose during storage. This requires an efficient L-arabinose isomerase acting at low temperature and pH values. Results The gene encoding the L-arabinose isomerase from Shewanella sp. ANA-3 was cloned and overexpressed in Escherichia coli. The purified protein has a tetrameric arrangement composed by four identical 55 kDa subunits. The biochemical characterization of this enzyme showed that it was distinguishable by its maximal activity at low temperatures comprised between 15-35°C. Interestingly, this biocatalyst preserves more than 85% of its activity in a broad range of temperatures from 4.0 to 45°C. Shewanella sp. ANA-3 L-arabinose isomerase was also optimally active at pH 5.5-6.5 and maintained over 80% of its activity at large pH values from 4.0 to 8.5. Furthermore, this enzyme exhibited a weak requirement for metallic ions for its activity evaluated at 0.6 mM Mn2+. Stability studies showed that this protein is highly stable mainly at low temperature and pH values. Remarkably, T268K mutation clearly enhances the enzyme stability at low pH values. Use of this L-arabinose isomerase for D-tagatose production allows the achievement of attractive bioconversion rates of 16% at 4°C and 34% at 35°C. Conclusions Here we reported the purification and the

  8. The acid-tolerant L-arabinose isomerase from the mesophilic Shewanella sp. ANA-3 is highly active at low temperatures

    Directory of Open Access Journals (Sweden)

    Rhimi Moez

    2011-11-01

    Full Text Available Abstract Background L-arabinose isomerases catalyse the isomerization of L-arabinose into L-ribulose at insight biological systems. At industrial scale of this enzyme is used for the bioconversion of D-galactose into D-tagatose which has many applications in pharmaceutical and agro-food industries. The isomerization reaction is thermodynamically equilibrated, and therefore the bioconversion rates is shifted towards tagatose when the temperature is increased. Moreover, to prevent secondary reactions it will be of interest to operate at low pH. The profitability of this D-tagatose production process is mainly related to the use of lactose as cheaper raw material. In many dairy products it will be interesting to produce D-tagatose during storage. This requires an efficient L-arabinose isomerase acting at low temperature and pH values. Results The gene encoding the L-arabinose isomerase from Shewanella sp. ANA-3 was cloned and overexpressed in Escherichia coli. The purified protein has a tetrameric arrangement composed by four identical 55 kDa subunits. The biochemical characterization of this enzyme showed that it was distinguishable by its maximal activity at low temperatures comprised between 15-35°C. Interestingly, this biocatalyst preserves more than 85% of its activity in a broad range of temperatures from 4.0 to 45°C. Shewanella sp. ANA-3 L-arabinose isomerase was also optimally active at pH 5.5-6.5 and maintained over 80% of its activity at large pH values from 4.0 to 8.5. Furthermore, this enzyme exhibited a weak requirement for metallic ions for its activity evaluated at 0.6 mM Mn2+. Stability studies showed that this protein is highly stable mainly at low temperature and pH values. Remarkably, T268K mutation clearly enhances the enzyme stability at low pH values. Use of this L-arabinose isomerase for D-tagatose production allows the achievement of attractive bioconversion rates of 16% at 4°C and 34% at 35°C. Conclusions Here we

  9. Evaluation of biomass of some invasive weed species as substrate for oyster mushroom (Pleurotus spp.) cultivation.

    Science.gov (United States)

    Mintesnot, Birara; Ayalew, Amare; Kebede, Ameha

    2014-01-15

    This study assessed the bioconversion of Agriculture wastes like invasive weeds species (Lantana camara, Prosopis juliflora, Parthenium hysterophorus) as a substrate for oyster mushroom (Pleurotus species) cultivation together with wheat straw as a control. The experiment was laid out in factorial combination of substrates and three edible oyster mushroom species in a Completely Randomized Design (CRD) with three replications. Pleurotus ostreatus gave significantly (p mushroom cultivation could contribute to alleviating ecological impact of invasive weed species while offering practical option to mitigating hunger and malnutrition in areas where the invasive weeds became dominant.

  10. Solar engineering 1995: Proceedings. Volume 1

    International Nuclear Information System (INIS)

    Stine, W.B.; Tanaka, Tadayoshi; Claridge, D.E.

    1995-01-01

    This is Volume 1 of the papers presented at the 1995 ASME/JSME/JSES International Solar Energy Conference. The topics of the papers include wind energy, heat pump performance, ground source and solar chemical heat pumps, analysis of measured building energy data, thermal storage, system modeling of buildings, evaluation of the Federal Building energy Efficiency program, sustainable projects, bioconversion, solar chemistry, solar detoxification innovative concepts and industrial applications, solar thermal power systems, DISH/engine power systems, power towers, solar thermal power advanced development, and solar thermal process heating and cooling

  11. Phytosanitary products

    International Nuclear Information System (INIS)

    1995-12-01

    One of a series of directories of Quebec universities, industrial and governmental agencies in Quebec actively involved in research and development of phytosanitary products or services derived from or associated with biomass products. This directory contained standardized entries for 79 organizations from the agriculture, forestry and environmental sectors, active in fields ranging from genetic engineering, fertilizers, crop diseases and pest management, forestry management, harvesting methods and bioconversion. Each entry provided information about major fields of research interest, principal technologies utilized, major equipment, personnel, and name and address of person to be contacted for further information. tabs

  12. The problem of wastes in the health sector

    International Nuclear Information System (INIS)

    Faysal, Al-Kak

    1998-01-01

    The article presents the management of hospital wastes in Lebanon. Hospital wastes considered as solid wastes, are divided into three main categories: radioactive wastes, contaminated wastes and chemical wastes. The treatment of wastes in the health sector in Lebanon is reduced to the incinerators. This method causes the major air pollution by emitting toxic substances as Dioxin. Advantages and disadvantages of alternate methods of wastes treatment are discussed such as: steam sterilization, bio-conversion, coal-burning, electronic radiation sterilization and chemical sterilization

  13. Biotechnology for energy

    International Nuclear Information System (INIS)

    Malik, K.A.; Naqvi, S.H.M.

    1991-01-01

    The present volume comprises paper presented and discussed in the symposium. The main purpose of this symposium was to collect researchers in the area of bioconversion of biomass into biofuels, petroleum biotechnology and biohydrometallurgy. This book has been divided into four main sections which includes molecular biology of biomass conversion, microbial conversion of biomass, petroleum biotechnology and biohydrometallurgy. It is becoming clear that biotechnology play a role in production and conservation of energy and can contribute to the overall energy situation. (A.B.)

  14. Fungal strains as catalysts for the biotransformation of halolactones by hydrolytic dehalogenation with the dimethylcyclohexane system.

    Science.gov (United States)

    Grabarczyk, Małgorzata

    2012-08-14

    Bicyclic chloro-, bromo- and iodo-γ-lactones with dimethylcyclohexane rings were used as substrates for bioconversion by several fungal strains (Fusarium, Botrytis and Beauveria). Most of the selected microorganisms transformed these lactones by hydrolytic dehalogenation into the new compound cis-2-hydroxy-4,6-dimethyl-9-oxabicyclo[4.3.0]- nonan-8-one, mainly the (-)-isomer. When iodo-γ-lactone was used as the substrate, two products were observed: a hydroxy-γ-lactone and an unsaturated lactone. The structures of all substrates and products were established on the basis of their spectral data. The mechanism of dehalogenation of three halolactones was also studied.

  15. A novel process for volatile fatty acids production from syngas by integrating with mesophilic alkaline fermentation of waste activated sludge

    DEFF Research Database (Denmark)

    Rao, Yue; Wan, Jingjing; Liu, Yafeng

    2018-01-01

    The present study proposed and demonstrated a novel process for the bioconversion of syngas (mainly CO and H2) to valuable volatile fatty acids (VFA) by integrating with mesophilic alkaline fermentation of waste activated sludge (WAS). The results showed that although pH 9 was suitable for VFA...... to the mesophilic alkaline fermentation of WAS at pH 10 not only resulted in the enrichment of some known bacteria related with syngas conversion, but also changed the microbial community compositions for the fermentation of WAS....

  16. Scalable preparation of high purity rutin fatty acid esters following enzymatic synthesis

    DEFF Research Database (Denmark)

    Lue, Bena-Marie; Guo, Zheng; Xu, Xuebing

    2010-01-01

    Investigations into expanded uses of modified flavonoids are often limited by the availability of these high purity compounds. As such, a simple, effective and relatively fast method for isolation of gram quantities of both long and medium chain fatty acid esters of rutin following scaled......-up biosynthesis reactions was established. Acylation reactions of rutin and palmitic or lauric acids were efficient in systems containing dried acetone and molecular sieves, yielding from 70–77% bioconversion after 96 h. Thereafter, high purity isolates (>97%) were easily obtained in significant quantities...

  17. Direct conversion of sorghum carbohydrates to ethanol by a mixed microbial culture

    Energy Technology Data Exchange (ETDEWEB)

    Christakopoulos, Paul; Lianwu Li; Kekos, Dimitris; Macris, B.J. (National Technical Univ. of Athens (Greece). Dept. of Chemical Engineering)

    1993-01-01

    The carbohydrates of sweet sorghum were directly converted to ethanol by a mixed culture of Fusarium oxysporum F3 and Saccharomyces cerevisiae 2541. A number of factors affecting this bioconversion was studied. Optimum ethanol yields of 33.2 g/100 g of total sorghum carbohydrates, corresponding to 10.3 g/100 g of fresh stalks, were obtained. These values represented 68.6% of the theoretical yield based on total polysaccharides and exceeded that based on oligosaccharides of sorghum by 53.7%. The results demonstrated that more than half of the sorghum polysaccharides were directly fermented to ethanol, thus making the process worthy of further investigation. (author)

  18. Energy from the ocean. Report of the Committee on Science and Technology, U. S. House of Representatives, Ninety-Fifth Congress, Second Session by the Science Policy Research Division, Congressional Research Service, Library of Congress

    Energy Technology Data Exchange (ETDEWEB)

    1978-01-01

    In the area of renewable sources of energy from the ocean, the report includes chapters on ocean thermal energy conversion; energy from ocean waves; energy from ocean currents; energy from tides; energy from oceanic winds; energy from salinity gradients; and energy from oceanic bioconversion. Also covered are the nonrenewable sources of energy from the ocean with chapters on deep ocean oil and gas; offshore geothermal energy; and offshore hard mineral energy resources. The report concludes with a bibliography and a selection of current articles on the general subject of the energy potential of the oceans.

  19. Saccharification of rice straw by cellulase from a local Trichoderma harzianum SNRS3 for biobutanol production.

    Science.gov (United States)

    Rahnama, Nooshin; Foo, Hooi Ling; Abdul Rahman, Nor Aini; Ariff, Arbakariya; Md Shah, Umi Kalsom

    2014-12-12

    Rice straw has shown to be a promising agricultural by-product in the bioconversion of biomass to value-added products. Hydrolysis of cellulose, a main constituent of lignocellulosic biomass, is a requirement for fermentable sugar production and its subsequent bioconversion to biofuels such as biobutanol. The high cost of commercial enzymes is a major impediment to the industrial application of cellulases. Therefore, the use of local microbial enzymes has been suggested. Trichoderma harzianum strains are potential CMCase and β-glucosidase producers. However, few researches have been reported on cellulase production by T. harzianum and the subsequent use of the crude cellulase for cellulose enzymatic hydrolysis. For cellulose hydrolysis to be efficiently performed, the presence of the whole set of cellulase components including exoglucanase, endoglucanase, and β-glucosidase at a considerable concentration is required. Biomass recalcitrance is also a bottleneck in the bioconversion of agricultural residues to value-added products. An effective pretreatment could be of central significance in the bioconversion of biomass to biofuels. Rice straw pretreated using various concentrations of NaOH was subjected to enzymatic hydrolysis. The saccharification of rice straw pretreated with 2% (w/v) NaOH using crude cellulase from local T. harzianum SNRS3 resulted in the production of 29.87 g/L reducing sugar and a yield of 0.6 g/g substrate. The use of rice straw hydrolysate as carbon source for biobutanol fermentation by Clostridium acetobutylicum ATCC 824 resulted in an ABE yield, ABE productivity, and biobutanol yield of 0.27 g/g glucose, 0.04 g/L/h and 0.16 g/g glucose, respectively. As a potential β-glucosidase producer, T. harzianum SNRS3 used in this study was able to produce β-glucosidase at the activity of 173.71 U/g substrate. However, for cellulose hydrolysis to be efficient, Filter Paper Activity at a considerable concentration is also required to initiate the

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

    Directory of Open Access Journals (Sweden)

    Magale K. D. Rambo

    2013-01-01

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

  1. Amide-transforming activity of Streptomyces: possible application to the formation of hydroxy amides and aminoalcohols.

    Science.gov (United States)

    Yamada, Shinya; Miyagawa, Taka-Aki; Yamada, Ren; Shiratori-Takano, Hatsumi; Sayo, Noboru; Saito, Takao; Takano, Hideaki; Beppu, Teruhiko; Ueda, Kenji

    2013-07-01

    To develop an efficient bioconversion process for amides, we screened our collection of Streptomyces strains, mostly obtained from soil, for effective transformers. Five strains, including the SY007 (NBRC 109343) and SY435 (NBRC 109344) of Streptomyces sp., exhibited marked conversion activities from the approximately 700 strains analyzed. These strains transformed diverse amide compounds such as N-acetyltetrahydroquinoline, N-benzoylpyrrolidine, and N-benzoylpiperidine into alcohols or N,O-acetals with high activity and regioselectivity. N,O-acetal was transformed into alcohol by serial tautomerization and reduction reactions. As such, Streptomyces spp. can potentially be used for the efficient preparation of hydroxy amides and aminoalcohols.

  2. Composition of cellulase complex of Clostridium thermocellum

    Energy Technology Data Exchange (ETDEWEB)

    Golovchenko, N P; Chuvil' skaya, N A; Akimenko, V K

    1985-01-01

    It is thought that the anaerobic thermophilic cellulolytic bacterium C. thermocellum has the potential for direct industrial bioconversion of cellulose into ethanol. Therefore, much attention has been given to the study of the cellulolytic properties of the culture and to the characteristics of the cellulose complex, which is still not completely understood. Hence, the activity and location of various cellulolytic enzymes of C. thermocellum were determined. C. thermocellum has 6 known cellulolytic enzymes. Endoglucanase, cellobiohydrolase and exoglucosidase are extracellular enzymes (99-100 percent of the activity is located outside the cells) while cellulobiases, cellobiose phosphorylase and cellodextrine phosphorylase are inside the cells (80-90% of the activity). 25 references.

  3. Process for preparing multilayer enzyme coating on a fiber

    Science.gov (United States)

    Kim, Jungbae [Richland, WA; Kwak, Ja Hun [Richland, WA; Grate, Jay W [West Richland, WA

    2009-11-03

    A process for preparing high stability, high activity biocatalytic materials is disclosed and processes for using the same. The process involves coating of a material or fiber with enzymes and enzyme aggregate providing a material or fiber with high biocatalytic activity and stability useful in heterogeneous environments. In one illustrative approach, enzyme "seeds" are covalently attached to polymer nanofibers followed by treatment with a reagent that crosslinks additional enzyme molecules to the seed enzymes forming enzyme aggregates thereby improving biocatalytic activity due to increased enzyme loading and enzyme stability. This approach creates a useful new biocatalytic immobilized enzyme system with potential applications in bioconversion, bioremediation, biosensors, and biofuel cells.

  4. A New Type of YumC-Like Ferredoxin (Flavodoxin) Reductase Is Involved in Ribonucleotide Reduction

    DEFF Research Database (Denmark)

    Chen, Jun; Shen, Jing; Solem, Christian

    2015-01-01

    . subtilis but that the addition of deoxynucleosides cannot compensate for the lethal phenotype displayed by the B. subtilis yumC knockout mutant. Ferredoxin (flavodoxin) reductase (FdR) is involved in many important reactions in both eukaryotes and prokaryotes, such as photosynthesis, nitrate reduction, etc. The recently...... ribonucleotide reductase, which represents the workhorse for the bioconversion of nucleotides to deoxynucleotides in many prokaryotes and eukaryotic pathogens under aerobic conditions. As the partner of the flavodoxin (NrdI), the key FdR is missing in the current model describing the class Ib system...

  5. Closing the Loop by Combining UASB Reactor and Reactive Bed Filetr Technology for wastewater Treatment : Modelling and Practical Approaches

    OpenAIRE

    Rodríguez-Gómez, Raúl

    2016-01-01

    A laboratory-scale upflow anaerobic sludge blanket (UASB) reactor followed by a packed bed reactor (PBR) filled with Sorbulite® in the lower part and Polonite® in the upper part was used to treat household wastewater in a 50-week experiment. A model was developed to describe the performance of the UASB reactor, including mass transfer through the film around anaerobic granules, intra-particle diffusion and bioconversion of the substrate. In a second model, a numerical expression describing th...

  6. Lipase-Catalyzed Esterification of Ferulic Acid with Oleyl Alcohol in Ionic Liquid/Isooctane Binary Systems

    DEFF Research Database (Denmark)

    Chen, Bilian; Liu, Huanzhen; Guo, Zheng

    2011-01-01

    Lipase-catalyzed synthesis of ferulic acid oleyl alcohol ester in an ionic liquid (IL)/isooctane system was investigated. Considerable bioconversion and volumetric productivity were achieved in inexpensive 1-hexyl-3-methylimidazolium hexafluorophosphate ([Hmim][PF6]) and 1-methyl-3-octylimidazolium....... Variations of the ratios of IL/isooctane and concentrations of oleyl alcohol also profoundly affected the volumetric productivity. To a higher extent, [Hmim][PF6]/isooctane and [Omim][PF6]/isooctane show similar reaction behaviors. Under the optimized reaction conditions (60 °C, 150 mg of Novozym 435 and 100...

  7. Toward a sustainable biorefinery using high-gravity technology

    DEFF Research Database (Denmark)

    Xiros, Charilaos; Janssen, Matty; Bystrom, Roberth

    2017-01-01

    The realization of process solutions for a sustainable bioeconomy depends on the efficient processing of biomass. High-gravity technology is one important alternative to realizing such solutions. The aims of this work were to expand the knowledge-base on lignocellulosic bioconversion processes...... at high solids content, to advance the current technologies for production of second-generation liquid biofuels, to evaluate the environmental impact of the proposed process by using life cycle assessment (LCA), and to develop and present a technically, economically, and environmentally sound process....... Biofuels, Bioproducts and Biorefining published by Society of Chemical Industry and John Wiley & Sons, Ltd....

  8. Co-ordinated research programme on development and application of isotopic techniques in studies of vitamin A nutrition. Report of the first research co-ordination meeting

    International Nuclear Information System (INIS)

    1997-01-01

    In Vitamin A nutrition, evaluations to ascertain the efficacy of intervention strategies are becoming increasingly important. However, state-of-the-art methods for evaluating vitamin A status often do not provide enough quantitative information on vitamin A status and the bioconversion of carotenoids, particularly in people with subclinical vitamin A deficiency. These limitations have had programmatic consequences. The principal reason the new Coordinated Research programme (CRP) was formulated was to improve techniques for measuring vitamin A status and the bioconversion of carotenoids to vitamin A with the expectation that the new methods could contribute meaningfully to field-based evaluations of the efficacy of intervention strategies. The International Atomic Energy Agency (IAEA) is sponsoring programmes to develop and transfer isotopic techniques to improve nutrition monitoring in developing countries. The New CRP ''Development and Application of Isotopic Techniques in Studies of Vitamin A Nutrition'' has seven teams, six of which are working to develop methods based on orally administered isotopically labelled retinol which will be a valid measure of whole body retinol (mostly hepatic reserves) and useful under typical field conditions, particularly in women and children with marginal vitamin A deficiency. The seventh team is biosynthesizing uniformly deuterated β-carotene by growing foods in deuterated water. This report summarizes the research to be undertaken, as presented at the first Research Co-ordination Meeting

  9. Characterization of Hydrocortisone Biometabolites and 18S rRNA Gene in Chlamydomonas reinhardtii Cultures

    Directory of Open Access Journals (Sweden)

    Seyed Bagher Mosavi-Azam

    2008-10-01

    Full Text Available A unicellular microalga, Chlamydomonas reinhardtii, was isolated from rice paddy-field soil and water samples and used in the biotransformation of hydrocortisone (1. This strain has not been previously tested for steroid bioconversion. Fermentation was carried out in BG-11 medium supplemented with 0.05% substrate at 25ºC for 14 days of incubation. The products obtained were chromatographically purified and characterized using spectroscopic methods. 11b,17b-Dihydroxyandrost-4-en-3-one (2, 11b-hydroxyandrost-4-en-3,17-dione (3, 11b,17a,20b,21-tetrahydroxypregn-4-en-3-one (4 and prednisolone (5 were the main products of the bioconversion. The observed bioreaction features were the side chain degradation of the substrate to give compounds 2 and 3 and the 20-ketone reduction and 1,2-dehydrogenation affording compounds 4 and 5, respectively. A time course study showed the accumulation of product 2 from the second day of the fermentation and of compounds 3, 4 and 5 from the third day. All the metabolites reached their maximum concentration in seven days. Microalgal 18S rRNA gene was also amplified by PCR. PCR products were sequenced to confirm their authenticity as 18S rRNA gene of microalgae. The result of PCR blasted with other sequenced microalgae in NCBI showed 100% homology to the 18S small subunit rRNA of two Chlamydomonas reinhardtii spp.

  10. Use of Vine-Trimming Wastes as Carrier for Amycolatopsis sp. to Produce Vanillin, Vanillyl Alcohol, and Vanillic Acid.

    Science.gov (United States)

    Castañón-Rodríguez, Juan Francisco; Pérez-Rodríguez, Noelia; de Souza Oliveira, Ricardo Pinheiro; Aguilar-Uscanga, María Guadalupe; Domínguez, José Manuel

    2016-10-01

    Raw vine-trimming wastes or the solid residues obtained after different fractionation treatments were evaluated for their suitability as Amycolatopsis sp. immobilization carriers during the bioconversion of ferulic acid into valuable phenolic compounds such as vanillin, vanillyl alcohol, and vanillic acid, the main flavor components of vanilla pods. Previously, physical-chemical characteristics of the materials were determined by quantitative acid hydrolysis and water absorption index (WAI), and microbiological characteristics by calculating the cell retention in the carrier (λ). Additionally, micrographics of carrier surface were obtained by field emission-scanning electron microscopy to study the influence of morphological changes during pretreatments in the adhesion of cells immobilized. The results point out that in spite of showing the lowest WAI and intermediate λ, raw material was the most appropriated substrate to conduct the bioconversion, achieving up to 262.9 mg/L phenolic compounds after 24 h, corresponding to 42.9 mg/L vanillin, 115.6 mg/L vanillyl alcohol, and 104.4 mg/L vanillic acid. The results showed the potential of this process to be applied for biotechnological production of vanillin from ferulic acid solutions; however, further studies must be carried out to increase vanillin yield. Additionally, the liquors obtained after treatment of vine-trimming wastes could be assayed to replace synthetic ferulic acid.

  11. Isolation of a Bacillus sp. capable of transforming isoeugenol to vanillin.

    Science.gov (United States)

    Shimoni, E; Ravid, U; Shoham, Y

    2000-02-28

    Natural aroma compounds are of major interest to the flavor and fragrance industry. Due to the limited sources for natural aromas, there is a growing interest in developing alternative sources for natural aroma compounds, and in particular aromatic aldehydes. In several microbial species aromatic aldehydes are detected as intermediates in the degradation pathway of phenylpropanoids. Thus, bioconversion of phenylpropanoids is one possible route for the production of these aroma compounds. The present work describes the isolation of microbial strains, capable of producing vanillin from isoeugenol. Bacterial strains isolated from soil, were screened for their ability to transform isoeugenol to vanillin. One of these strains, strain B2, was found to produce high amounts of vanillin when grown in the presence of isoeugenol, and was also capable of growing on isoeugenol as the sole carbon source. Based on its fatty acids profile, strain B2 was identified as a Bacillus subtilis sp. The bioconversion capabilities of strain B2 were tested in growing cultures and cell free extracts. In the presence of isoeugenol, a growing cultures of B. subtilis B2 produced 0.61 g l-1 vanillin (molar yield of 12.4%), whereas cell free extracts resulted in 0.9 g l-1 vanillin (molar yield of 14%).

  12. Effect of methyl-β-cyclodextrin on gene expression in microbial conversion of phytosterol.

    Science.gov (United States)

    Shtratnikova, Victoria Y; Schelkunov, Mikhail I; Dovbnya, Dmitry V; Bragin, Eugeny Y; Donova, Marina V

    2017-06-01

    Modified β-cyclodextrins are widely used for the enhancement of microbial conversions of lipophilic compounds such as steroids. Multiple mechanisms of cyclodextrin-mediated enhancement of phytosterol bioconversion by mycobacteria had previously been shown to include steroid solubilization, alterations in the cell wall permeability for both steroids and nutrients, facilitation of protein leaking, and activity suppression of some steroid-transforming enzymes.In this work, we studied whether cyclodextrins might affect expression of the genes involved in the steroid catabolic pathway. Phytosterol bioconversion with 9α-hydroxy-androst-4-ene-3,17-dione accumulation by Mycobacterium sp. VKM Ac-1817D in the presence of methylated β-cyclodextrin (MCD) was investigated. RNA sequencing of the whole transcriptomes in different combinations of phytosterol and MCD showed a similar expression level of the steroid catabolism genes related to the KstR-regulon and was responsible for side chain and initial steps of steroid core oxidation; whereas, induction levels of the genes related to the KstR2-regulon were attenuated in the presence of MCD in this strain. The data were attenuated with quantitative real-time PCR.The results contribute to the understanding of cyclodextrin effects on microbial steroid conversion and provide a basis for the use of cyclodextrins as expression enhancers for studies of sterol catabolism in actinobacteria.

  13. Use of Jatropha curcas hull biomass for bioactive compost production

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, D.K. [Division of Environmental Sciences, Indian Agricultural Research Institute, New Delhi 110012 (India); Pandey, A.K.; Lata [Division of Microbiology, Indian Agricultural Research Institute, New Delhi 110012 (India)

    2009-01-15

    The paper deals with utilization of biomass of Jatropha hulls for production of bioactive compost. In the process of Jatropha oil extraction, a large amount of hull waste is generated. It has been found that the direct incorporation of hull into soil is considerably inefficient in providing value addition to soil due to its unfavorable physicochemical characteristics (high pH, EC and phenolic content). An alternative to this problem is the bioconversion of Jatropha hulls using effective lignocellulolytic fungal consortium, which can reduce the phytotoxicity of the degraded material. Inoculation with the fungal consortium resulted in better compost of jatropha hulls within 1 month, but it takes nearly 4 months for complete compost maturation as evident from the results of phytotoxicity test. Such compost can be applied to the acidic soil as a remedial organic manure to help maintaining sustainability of the agro-ecosystem. Likewise, high levels of cellulolytic enzymes observed during bioconversion indicate possible use of fungi for ethanol production from fermentation of hulls. (author)

  14. Construction of a highly efficient Bacillus subtilis 168 whole-cell biocatalyst and its application in the production of L-ornithine.

    Science.gov (United States)

    Wang, Meizhou; Xu, Meijuan; Rao, Zhiming; Yang, Taowei; Zhang, Xian

    2015-11-01

    L-Ornithine, a non-protein amino acid, is usually extracted from hydrolyzed protein as well as produced by microbial fermentation. Here, we focus on a highly efficient whole-cell biocatalyst for the production of L-ornithine. The gene argI, encoding arginase, which catalyzes the hydrolysis of L-arginine to L-ornithine and urea, was cloned from Bacillus amyloliquefaciens B10-127 and expressed in GRAS strain Bacillus subtilis 168. The recombinant strain exhibited an arginase activity of 21.9 U/mg, which is 26.7 times that of wild B. subtilis 168. The optimal pH and temperature of the purified recombinant arginase were 10.0 and 40 °C, respectively. In addition, the recombinant arginase exhibited a strong Mn(2+) preference. When using whole-cell biocatalyst-based bioconversion, a hyper L-ornithine production of 356.9 g/L was achieved with a fed-batch strategy in a 5-L reactor within 12 h. This whole-cell bioconversion study demonstrates an environmentally friendly strategy for L-ornithine production in industry.

  15. Lactic acid production from unmatured banana peel and flesh through simultaneous saccharification and fermentation

    Directory of Open Access Journals (Sweden)

    Mohammed BELMAKKI

    2016-07-01

    Full Text Available The aim of this study was to establish a process of lactic acid (LA production from two different kinds of african organic waste i.e. peel and flesh of un-matured banana by using as model strain Lactobacillus bp Pentosus AH 239. The bioconversion of glucose contained in the biomass to LA was performed following the Simultaneous Saccharification and Fermentation (SSF process. The Separated Hydrolysis and Fermentation (SHF was also applied in this study to compare the efficiency of both process. The results showed that the enzymatic hydrolysis yield was significantly improved in case of SSF recording a rate of hydrolysis in the range of 82%-90% against 52%-61% under SHF conditions. The results showed also that SSF give more efficient lactic acid production with a yield above of 90%, and a high concentration up to 50 g/L. Due to its performance, the SSF process for the lactic acid production could be an important way of bioconversion for lignocellulosic residues in Africa. The optimization of this process need to be adapted for African context and for its development on an industrial scale.

  16. Biosynthesis of tert-butyl (3R,5S)-6-chloro-3,5-dihydroxyhexanoate by carbonyl reductase from Rhodosporidium toruloides in mono and biphasic media.

    Science.gov (United States)

    Liu, Zhi-Qiang; Wu, Lin; Zheng, Ling; Wang, Wen-Zhong; Zhang, Xiao-Jian; Jin, Li-Qun; Zheng, Yu-Guo

    2018-02-01

    tert-Butyl (3R,5S)-6-chloro-3,5-dihydroxyhexanoate ((3R,5S)-CDHH) is the key intermediate for synthesis of atorvastatin and rosuvastatin. Carbonyl reductase exhibits excellent activity toward tert-butyl (S)-6-chloro-5-hydroxy-3-oxohexanoate ((S)-CHOH) to synthesize (3R,5S)-CDHH. In this study, a whole cell biosynthesis reaction system to produce (3R,5S)-CDHH was constructed in organic solvents. A solution of 10% (v/v) Tween-80 was introduced to the reaction system as a co-solvent, which greatly enhanced biotransformation process, giving 98.9% yield, >99% ee and 1.8-fold higher space time yield in 5 h bioconversion of 1 M (S)-CHOH, compared with 98.7% yield and >99% ee in 9 h bioconversion of a purely aqueous reaction system. Moreover, a water-octanol biphasic reaction system was built and 20% of octanol was added as reservoir of substrate resulting in 98% yield, >99% ee and 4.08 mmol L -1  h -1  g -1 (wet cell weight) space time yield. This study paved a way for the whole cell biosynthesis of (3R,5S)-CDHH in mono and biphasic media. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Evaluation of process performance, energy consumption and microbiota characterization in a ceramic membrane bioreactor for ex-situ biomethanation of H2 and CO2.

    Science.gov (United States)

    Alfaro, Natalia; Fdz-Polanco, María; Fdz-Polanco, Fernando; Díaz, Israel

    2018-06-01

    The performance of a pilot ceramic membrane bioreactor for the bioconversion of H 2 and CO 2 to bioCH 4 was evaluated in thermophilic conditions. The loading rate was between 10 and 30 m 3  H 2 /m 3 reactor  d and the system transformed 95% of H 2 fed. The highest methane yield found was 0.22 m 3  CH 4 /m 3  H 2 , close to the maximum stoichiometric value (0.25 m 3  CH 4 /m 3  H 2 ) thus indicating that archaeas employed almost all H 2 transferred to produce CH 4 . k L a value of 268 h -1 was reached at 30 m 3  H 2 /m 3 reactor  d. DGGE and FISH revealed a remarkable archaeas increase related to the selection-effect of H 2 on community composition over time. Methanothermobacter thermautotrophicus was the archaea found with high level of similarity. This study verified the successful application of membrane technology to efficiently transfer H 2 from gas to the liquid phase, the development of a hydrogenotrophic community from a conventional thermophilic sludge and the technical feasibility of the bioconversion. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. Complete biocycle for solar energy conversion, storage, fuel and power generation, and coal conservation for future use

    International Nuclear Information System (INIS)

    Srivastava, S.C.

    1993-01-01

    A complete carbon biocycle has been described, starting from coal in in situ condition in coal seams underground. Various steps involved are: (i) Biogasification of coal to methane, using a consortia of bacteria, has been reported. A group of bacteria degrades complex structure of coal to simpler structure. This simpler structure of coal, is then converted to methane by methanogens; (ii) Biophotolysis of methane and associated biodegradation, results in products, such as hydrogen and oxygen for use in fuel cells for power generation; (iii) Bioconversion of products so obtained is carried out to produce methanol or methane that could be used as fuel or recycled; (iv) In complete biocycle some methane is converted to biomass. In order to replace this methane, coal is converted to methane using group of bacteria, only to the extent methane has been converted to biomass; (v) The biomass so produced could be dumped underground from where coal has been gasified. Alternatively it could be burnt as fuel or else used as substitute of protein in animal food. Detailed concept of proposed technology for: (a) an alternative to conventional coal mining, (b) generation of power using products of bioconversion in fuel cell, and (c) conversation of solar energy for generation of alternative source of fuel and power, has been discussed. Possibility of developing a biofuel cell for conversion of solar energy through bioelectrochemical route has been suggested. (author). 48 refs., 3 figs

  19. The Study of the Viermicompost Influence on the Harvest and on the Quality of Forage Cultures

    Directory of Open Access Journals (Sweden)

    Larisa Cremeneac

    2011-10-01

    Full Text Available The purpose of the research was the appreciation of the viermicompost quality. This material was obtained as a result of bioconversion of organically wastes (obtained from cattle by worm cultivation, using wormculture (especially the Red Hybrid of California. The bioconversion process of organic wastes is implemented in the Experimental Section of the Scientific and Practical Institute of Biotechnologies in Animal Husbandry and Veterinary Medicine. As a result of the studies to effect in several states, including the Republic of Moldova, it has been stated that the veirmicompost has a positive influence on the productivity of cultures, diminishing the period of culture growing , increases their resistance to infavorable clamaterical conditions and to frequent phitotechnical maligns. In the agricultural production obtained as a result of cultivating on viermicompost. As a result of the research it has dean stated that the quantity of the C vitamin in some of the vegetables has increased by 1,5 – 9,4 times. What s more the viermicompost has influenced positively the quality of the alfalfa, maize and sugar fodder, in which the azoth compounds quantity has diminished by 1,32 – 2,66; 3,47 – 3,76 and 1,10 – 1,14 times, in comparison with cultures cultivars tied with the help of mineral fertilizer. So, the agricultural and ecological importance of the viermicompost consists in improving the quality of agricultural production.

  20. IDENTIFIKASI POTENSI ENZIM LIPASE DAN SELULASE PADA SAMPAH KULIT BUAH HASIL FERMENTASI

    Directory of Open Access Journals (Sweden)

    La Ode Sumarlin

    2013-12-01

    Full Text Available Fermentation is one of bioconversion to produce profitable anaerobic microbes and to produce various enzymes. Lipases and cellulases are widely used enzymes so far. Cellulases play an important role in bioconversion of organic waste cellulosic materials to glucose, single cell proteins, animal feed, and ethanol. Lipases can also degrade fatty ester bond. Therefore, both enzymes are potential to be used in industry as well as in households. Fermentation of fruit peel waste is an attempt to produce cellulase and lipase that can be carried out in a simple way. Cellulase as says was performed using DNS (3.5-dinitrosalicylic acid and acid-base titration for analysis of lipase using cooking oil as the substrate. The results showed that the highest cellulase activity was obtained from watermelon rind mixed with citrus fruit peel of 0.036 U/mL, and mixed of banana peel and citrus fruit, which was 0.035 U/mL. The optimum lipase activity was at 30 oC, pH 7, and reaction time of 60 minutes. The highest lipase activity (1.36 U/mL was obtained from mixture of watermelon and orange rind. Thus, the fruit peel waste is potential to produce cellulase and lipase by fermentation .

  1. Investigation of the available technologies and their feasibility for the conversion of food waste into fish feed in Hong Kong.

    Science.gov (United States)

    Cheng, Jack Y K; Lo, Irene M C

    2016-04-01

    Food waste is the largest constituent of municipal solid waste in Hong Kong, but food waste recycling is still in its infancy. With the imminent saturation of all landfill sites by 2020, multiple technologies are needed to boost up the food waste recycling rate in Hong Kong. Conversion of food waste into animal feeds is prevalent in Japan, South Korea, and Taiwan, treating over 40 % of their recycled food waste. This direction is worth exploring in Hong Kong once concerns over food safety are resolved. Fortunately, while feeding food waste to pigs and chickens poses threats to public health, feeding it to fish is considered low risk. In order to examine the feasibility of converting food waste into fish feed in Hong Kong, this paper investigates the market demand, technical viability, feed quality, regulatory hurdles, and potential contribution. The results show that a significant amount of food waste can be recycled by converting it into fish feed due to the enormous demand from feed factories in mainland China. Two conversion technologies, heat drying and black soldier fly bioconversion, are studied extensively. Black soldier fly bioconversion is preferable because the end-product, insect powder, is anticipated to gain import approval from mainland China. The authors suggest further research efforts to speed up its application for food waste recycling in urban cities.

  2. Oligosaccharides in feces of breast- and formula-fed babies.

    Science.gov (United States)

    Albrecht, Simone; Schols, Henk A; van Zoeren, Diny; van Lingen, Richard A; Groot Jebbink, Liesbeth J M; van den Heuvel, Ellen G H M; Voragen, Alphons G J; Gruppen, Harry

    2011-10-18

    So far, little is known on the fate of oligosaccharides in the colon of breast- and formula-fed babies. Using capillary electrophoresis with laser induced fluorescence detector coupled to a mass spectrometer (CE-LIF-MS(n)), we studied the fecal oligosaccharide profiles of 27 two-month-old breast-, formula- and mixed-fed preterm babies. The interpretation of the complex oligosaccharide profiles was facilitated by beforehand clustering the CE-LIF data points by agglomerative hierarchical clustering (AHC). In the feces of breast-fed babies, characteristic human milk oligosaccharide (HMO) profiles, showing genetic fingerprints known for human milk of secretors and non-secretors, were recognized. Alternatively, advanced degradation and bioconversion of HMOs, resulting in an accumulation of acidic HMOs or HMO bioconversion products was observed. Independent of the prebiotic supplementation of the formula with galactooligosaccharides (GOS) at the level used, similar oligosaccharide profiles of low peak abundance were obtained for formula-fed babies. Feeding influences the presence of diet-related oligosaccharides in baby feces and gastrointestinal adaptation plays an important role herein. Four fecal oligosaccharides, characterized as HexNAc-Hex-Hex, Hex-[Fuc]-HexNAc-Hex, HexNAc-[Fuc]-Hex-Hex and HexNAc-[Fuc]-Hex-HexNAc-Hex-Hex, highlighted an active gastrointestinal metabolization of the feeding-related oligosaccharides. Their presence was linked to the gastrointestinal mucus layer and the blood-group determinant oligosaccharides therein, which are characteristic for the host's genotype. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. Bridging the gap between feedstock growers and users: the study of a coppice poplar-based biorefinery.

    Science.gov (United States)

    Dou, Chang; Gustafson, Rick; Bura, Renata

    2018-01-01

    In the biofuel industry, land productivity is important to feedstock growers and conversion process product yield is important to the biorefinery. The crop productivity, however, may not positively correlate with bioconversion yield. Therefore, it is important to evaluate sugar yield and biomass productivity. In this study, 2-year-old poplar trees harvested in the first coppice cycle, including one low-productivity hybrid and one high-productivity hybrid, were collected from two poplar tree farms. Through steam pretreatment and enzymatic hydrolysis, the bioconversion yields of low- and high-productivity poplar hybrids were compared for both sites. The low-productivity hybrids had 9-19% higher sugar yields than the high-productivity hybrids, although they have the similar chemical composition. Economic calculations show the impact on the plantation and biorefinery of using the two feedstocks. Growing a high-productivity hybrid means the land owner would use 11-26% less land (which could be used for other crops) or collect $2.53-$3.46 MM/year extra revenue from the surplus feedstock. On the other side, the biorefinery would receive 5-10% additional revenue using the low-productivity hybrid. We propose a business model based on the integration of the plantation and the biorefinery. In this model, different feedstocks are assessed using a metric of product tonnage per unit land per year. Use of this new economic metric bridges the gap between feedstock growers and users to maximize the overall production efficiency.

  4. Isolation and Characterization of a Human Intestinal Bacterium Eggerthella sp. AUH-JLD49s for the Conversion of (-)-3'-Desmethylarctigenin.

    Science.gov (United States)

    Wang, Ye; Yu, Fei; Liu, Ming-Yue; Zhao, Yi-Kai; Wang, Dong-Ming; Hao, Qing-Hong; Wang, Xiu-Ling

    2017-05-24

    Arctiin is the most abundant bioactive compound contained in the Arctium lappa plant. In our previous study, we isolated one single bacterium capable of bioconverting arctigenin, an aglycone of arctiin, to 3'-desmethylarctigenin (3'-DMAG) solely. However, to date, a specific bacterium capable of producing other arctiin metabolites has not been reported. In this study, we isolated one single bacterium, which we named Eggerthella sp. AUH-JLD49s, capable of bioconverting 3'-DMAG under anaerobic conditions. The metabolite of 3'-DMAG by strain AUH-JLD49s was identified as 3'-desmethyl-4'-dehydroxyarctigenin (DMDH-AG) based on electrospray ionization mass spectrometry (ESI-MS) and 1 H and 13 C nuclear magnetic resonance spectroscopy. The bioconversion kinetics and bioconversion capacity of strain AUH-JLD49s were investigated. In addition, the metabolite DMDH-AG showed an inhibitory effect on cell growth of human colon cancer cell line HCT116 and human breast cancer cell line MDA-MB-231.

  5. Biotechnology of intensive aerobic conversion of sewage sludge and food waste into fertilizer

    Energy Technology Data Exchange (ETDEWEB)

    Wang, J.-Y.; Stabnikova, O.; Show, K.-Y.; Ding, H.-B.; Tay, S.T.-L.; Ivanov, V.; Tay, J.-H.

    2003-07-01

    Biotechnology for intensive aerobic bioconversion of sewage sludge and food waste into fertilizer was developed. The wastes were treated in a closed reactor under controlled aeration, stirring, pH, and temperature at 60{sup o}C, after addition of starter bacterial culture Bacillus thermoamylovorans. The biodegradation of sewage sludge was studied by decrease of volatile solids (VS), content of organic carbon and autofluorescence of coenzyme F{sub 420}. The degradation of anaerobic biomass was faster than biodegradation of total organic matter. The best fertilizer was obtained when sewage sludge was thermally pre-treated, mixed with food waste, chalk, and artificial bulking agent. The content of volatile solid and the content of organic carbon decreased at 24.8% and 13.5% of total solids, respectively, during ten days of bioconversion. The fertilizer was a powder with moisture content of 5%. It was stable, and not toxic for the germination of plant seeds. Addition of 1.0 to 1.5% of this fertilizer to the subsoil increased the growth of different plants tested by 113 to 164 %. The biotechnology can be applied in larger scale for the recycling of sewage sludge and food wastes in Singapore. (author)

  6. A metabolic pathway for catabolizing levulinic acid in bacteria

    International Nuclear Information System (INIS)

    Rand, Jacqueline M.; Pisithkul, Tippapha; Clark, Ryan L.; Thiede, Joshua M.; Mehrer, Christopher R.

    2017-01-01

    Microorganisms can catabolize a wide range of organic compounds and therefore have the potential to perform many industrially relevant bioconversions. One barrier to realizing the potential of biorefining strategies lies in our incomplete knowledge of metabolic pathways, including those that can be used to assimilate naturally abundant or easily generated feedstocks. For instance, levulinic acid (LA) is a carbon source that is readily obtainable as a dehydration product of lignocellulosic biomass and can serve as the sole carbon source for some bacteria. Yet, the genetics and structure of LA catabolism have remained unknown. Here, we report the identification and characterization of a seven-gene operon that enables LA catabolism in Pseudomonas putida KT2440. When the pathway was reconstituted with purified proteins, we observed the formation of four acyl-CoA intermediates, including a unique 4-phosphovaleryl-CoA and the previously observed 3-hydroxyvaleryl-CoA product. Using adaptive evolution, we obtained a mutant of Escherichia coli LS5218 with functional deletions of fadE and atoC that was capable of robust growth on LA when it expressed the five enzymes from the P. putida operon. Here, this discovery will enable more efficient use of biomass hydrolysates and metabolic engineering to develop bioconversions using LA as a feedstock.

  7. Development of the University of Washington Biofuels and Biobased Chemicals Process Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Gustafson, Richard [University of Washington

    2014-02-04

    The funding from this research grant enabled us to design and build a bioconversion steam explosion reactor and ancillary equipment such as a high pressure boiler and a fermenter to support the bioconversion process research. This equipment has been in constant use since its installation in 2012. Following are research projects that it has supported: • Investigation of novel chip production method in biofuels production • Investigation of biomass refining following steam explosion • Several studies on use of different biomass feedstocks • Investigation of biomass moisture content on pretreatment efficacy. • Development of novel instruments for biorefinery process control Having this equipment was also instrumental in the University of Washington receiving a $40 million grant from the US Department of Agriculture for biofuels development as well as several other smaller grants. The research that is being done with the equipment from this grant will facilitate the establishment of a biofuels industry in the Pacific Northwest and enable the University of Washington to launch a substantial biofuels and bio-based product research program.

  8. Methanogenic degradation of toilet-paper cellulose upon sewage treatment in an anaerobic membrane bioreactor at room temperature.

    Science.gov (United States)

    Chen, Rong; Nie, Yulun; Kato, Hiroyuki; Wu, Jiang; Utashiro, Tetsuya; Lu, Jianbo; Yue, Shangchao; Jiang, Hongyu; Zhang, Lu; Li, Yu-You

    2017-03-01

    Toilet-paper cellulose with rich but refractory carbon sources, are the main insoluble COD fractions in sewage. An anaerobic membrane bioreactor (AnMBR) was configured for sewage treatment at room temperature and its performance on methanogenic degradation of toilet paper was highlighted. The results showed, high organic removal (95%), high methane conversion (90%) and low sludge yield (0.08gVSS/gCOD) were achieved in the AnMBR. Toilet-paper cellulose was fully biodegraded without accumulation in the mixed liquor and membrane cake layer. Bioconversion efficiency of toilet paper approached 100% under a high organic loading rate (OLR) of 2.02gCOD/L/d and it could provide around 26% of total methane generation at most of OLRs. Long sludge retention time and co-digestion of insoluble/soluble COD fractions achieving mutualism of functional microorganisms, contributed to biodegradation of toilet-paper cellulose. Therefore the AnMBR successfully implemented simultaneously methanogenic bioconversion of toilet-paper cellulose and soluble COD in sewage at room temperature. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Biotechnological production of pharmaceuticals and biopharmaceuticals in plant cell and organ cultures.

    Science.gov (United States)

    Hidalgo, Diego; Sanchez, Raul; Lalaleo, Liliana; Bonfill, Mercedes; Corchete, Purificacion; Palazon, Javier

    2018-03-09

    Plant biofactories are biotechnological platforms based on plant cell and organ cultures used for the production of pharmaceuticals and biopharmaceuticals, although to date only a few of these systems have successfully been implemented at an industrial level. Metabolic engineering is possibly the most straightforward strategy to boost pharmaceutical production in plant biofactories, but social opposition to the use of GMOs means empirical approaches are still being used. Plant secondary metabolism involves thousands of different enzymes, some of which catalyze specific reactions, giving one product from a particular substrate, whereas others can yield multiple products from the same substrate. This trait opens plant cell biofactories to new applications, in which the natural metabolic machinery of plants can be harnessed for the bioconversion of phytochemicals or even the production of new bioactive compounds. Synthetic biological pipelines involving the bioconversion of natural substrates into products with a high market value may be established by the heterologous expression of target metabolic genes in model plants. To summarize the state of the art of plant biofactories and their applications for the pipeline production of cosme-, pharma- and biopharmaceuticals. In order to demonstrate the great potential of plant biofactories for multiple applications in the biotechnological production of pharmaceuticals and biopharmaceuticals, this review broadly covers the following: plant biofactories based on cell and hairy root cultures; secondary metabolite production; biotransformation reactions; metabolic engineering tools applied in plant biofactories; and biopharmaceutical production. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  10. Life cycle evaluation of emerging lignocellulosic ethanol conversion technologies.

    Science.gov (United States)

    Spatari, Sabrina; Bagley, David M; MacLean, Heather L

    2010-01-01

    Lignocellulosic ethanol holds promise for addressing climate change and energy security issues associated with personal transportation through lowering the fuel mixes' carbon intensity and petroleum demand. We compare the technological features and life cycle environmental impacts of near- and mid-term ethanol bioconversion technologies in the United States. Key uncertainties in the major processes: pre-treatment, hydrolysis, and fermentation are evaluated. The potential to reduce fossil energy use and greenhouse gas (GHG) emissions varies among bioconversion processes, although all options studied are considerably more attractive than gasoline. Anticipated future performance is found to be considerably more attractive than that published in the literature as being achieved to date. Electricity co-product credits are important in characterizing the GHG impacts of different ethanol production pathways; however, in the absence of near-term liquid transportation fuel alternatives to gasoline, optimizing ethanol facilities to produce ethanol (as opposed to co-products) is important for reducing the carbon intensity of the road transportation sector and for energy security.

  11. Metabolic Engineering toward Sustainable Production of Nylon-6.

    Science.gov (United States)

    Turk, Stefan C H J; Kloosterman, Wigard P; Ninaber, Dennis K; Kolen, Karin P A M; Knutova, Julia; Suir, Erwin; Schürmann, Martin; Raemakers-Franken, Petronella C; Müller, Monika; de Wildeman, Stefaan M A; Raamsdonk, Leonie M; van der Pol, Ruud; Wu, Liang; Temudo, Margarida F; van der Hoeven, Rob A M; Akeroyd, Michiel; van der Stoel, Roland E; Noorman, Henk J; Bovenberg, Roel A L; Trefzer, Axel C

    2016-01-15

    Nylon-6 is a bulk polymer used for many applications. It consists of the non-natural building block 6-aminocaproic acid, the linear form of caprolactam. Via a retro-synthetic approach, two synthetic pathways were identified for the fermentative production of 6-aminocaproic acid. Both pathways require yet unreported novel biocatalytic steps. We demonstrated proof of these bioconversions by in vitro enzyme assays with a set of selected candidate proteins expressed in Escherichia coli. One of the biosynthetic pathways starts with 2-oxoglutarate and contains bioconversions of the ketoacid elongation pathway known from methanogenic archaea. This pathway was selected for implementation in E. coli and yielded 6-aminocaproic acid at levels up to 160 mg/L in lab-scale batch fermentations. The total amount of 6-aminocaproic acid and related intermediates generated by this pathway exceeded 2 g/L in lab-scale fed-batch fermentations, indicating its potential for further optimization toward large-scale sustainable production of nylon-6.

  12. Grain sorghum is a viable feedstock for ethanol production.

    Science.gov (United States)

    Wang, D; Bean, S; McLaren, J; Seib, P; Madl, R; Tuinstra, M; Shi, Y; Lenz, M; Wu, X; Zhao, R

    2008-05-01

    Sorghum is a major cereal crop in the USA. However, sorghum has been underutilized as a renewable feedstock for bioenergy. The goal of this research was to improve the bioconversion efficiency for biofuels and biobased products from processed sorghum. The main focus was to understand the relationship among "genetics-structure-function-conversion" and the key factors impacting ethanol production, as well as to develop an energy life cycle analysis model (ELCAM) to quantify and prioritize the saving potential from factors identified in this research. Genetic lines with extremely high and low ethanol fermentation efficiency and some specific attributes that may be manipulated to improve the bioconversion rate of sorghum were identified. In general, ethanol yield increased as starch content increased. However, no linear relationship between starch content and fermentation efficiency was found. Key factors affecting the ethanol fermentation efficiency of sorghum include protein digestibility, level of extractable proteins, protein and starch interaction, mash viscosity, amount of phenolic compounds, ratio of amylose to amylopectin, and formation of amylose-lipid complexes in the mash. A platform ELCAM with a base case showed a positive net energy value (NEV) = 25,500 Btu/gal EtOH. ELCAM cases were used to identify factors that most impact sorghum use. For example, a yield increase of 40 bu/ac resulted in NEV increasing from 7 million to 12 million Btu/ac. An 8% increase in starch provided an incremental 1.2 million Btu/ac.

  13. Co-ordinated research programme on development and application of isotopic techniques in studies of vitamin A nutrition. Report of the first research co-ordination meeting

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-12-31

    In Vitamin A nutrition, evaluations to ascertain the efficacy of intervention strategies are becoming increasingly important. However, state-of-the-art methods for evaluating vitamin A status often do not provide enough quantitative information on vitamin A status and the bioconversion of carotenoids, particularly in people with subclinical vitamin A deficiency. These limitations have had programmatic consequences. The principal reason the new Coordinated Research programme (CRP) was formulated was to improve techniques for measuring vitamin A status and the bioconversion of carotenoids to vitamin A with the expectation that the new methods could contribute meaningfully to field-based evaluations of the efficacy of intervention strategies. The International Atomic Energy Agency (IAEA) is sponsoring programmes to develop and transfer isotopic techniques to improve nutrition monitoring in developing countries. The New CRP ``Development and Application of Isotopic Techniques in Studies of Vitamin A Nutrition`` has seven teams, six of which are working to develop methods based on orally administered isotopically labelled retinol which will be a valid measure of whole body retinol (mostly hepatic reserves) and useful under typical field conditions, particularly in women and children with marginal vitamin A deficiency. The seventh team is biosynthesizing uniformly deuterated {beta}-carotene by growing foods in deuterated water. This report summarizes the research to be undertaken, as presented at the first Research Co-ordination Meeting. Refs, figs, tabs.

  14. Screening tests for assessing the anaerobic biodegradation of pollutant chemicals in subsurface environments

    Science.gov (United States)

    Suflita, Joseph M.; Concannon, Frank

    1995-01-01

    Screening methods were developed to assess the susceptibility of ground water contaminants to anaerobic biodegradation. One method was an extrapolation of a procedure previously used to measure biodegradation activity in dilute sewage sludge. Aquifer solids and ground water with no additional nutritive media were incubated anaerobically in 160-ml serum bottles containing 250 mg·l−1 carbon of the substrate of interest. This method relied on the detection of gas pressure or methane production in substrateamended microcosms relative to background controls. Other screening procedures involved the consumption of stoichiometrically required amounts of sulfate or nitrate from the same type of incubations. Close agreement was obtained between the measured and calculated amounts of substrate bioconversion based on the measured biogas pressure in methanogenic microcosms. Storage of the microcosms for up to 6 months did not adversely influence the onset or rate of benzoic acid mineralization. The lower detection limits of the methanogenic assay were found to be a function of the size of the microcosm headspace, the mean oxidation state of the substrate carbon, and the method used to correct for background temperature fluctuations. Using these simple screening procedures, biodegradation information of regulatory interest could be generated, including, (i) the length of the adaptation period, (ii) the rate of substrate decay and (iii) the completeness of the bioconversion.

  15. Diversity of Lactobacillus reuteri Strains in Converting Glycerol into 3-Hydroxypropionic Acid.

    Science.gov (United States)

    Burgé, G; Saulou-Bérion, C; Moussa, M; Pollet, B; Flourat, A; Allais, F; Athès, V; Spinnler, H E

    2015-10-01

    The present study aims at comparing the performances of three Lactobacillus reuteri strains (DSM 20016, DSM 17938, and ATCC 53608) in producing 3-hydroxypropionic acid (3-HP) from glycerol and at exploring inhibition phenomena during this bioconversion. Differences were highlighted between the three strains in terms of 3-HP production yield, kinetics of substrate consumption, and metabolite production. With a maximal productivity in non-optimal conditions (free pH) around 2 g.L(-1).h(-1) of 3-HP and 4 g.L(-1).h(-1) of 3-hydroxypropionaldehyde (3-HPA) depending on the strain, this study confirmed the potential of L. reuteri for the biotechnological production of 3-HP. Moreover, the molar ratios of 3-HP to 1,3-propanediol (1,3-PDO) obtained for the three strains (comprised between 1.25 and 1.65) showed systematically a higher 3-HP production. From these results, the DSM 17938 strain appeared to be the most promising strain. The impact of glycerol bioconversion on the bacteria's physiological state (a decrease of around 40 % in DSM 17938 cells showing an enzymatic activity after 3 h) and survival (total loss of cultivability after 2 or 3 h depending on the strains) was revealed and discussed. The effect of each metabolite on L. reuteri DSM 17938 was further investigated, displaying a drastic inhibition caused by 3-HPA, while 3-HP induced lower impact and only at acidic pH.

  16. Characterization of hydrocortisone biometabolites and 18S rRNA gene in Chlamydomonas reinhardtii cultures.

    Science.gov (United States)

    Ghasemi, Younes; Rasoul-Amini, Sara; Morowvat, Mohammad Hossein; Raee, Mohammad Javad; Ghoshoon, Mohammad Bagher; Nouri, Fatemeh; Negintaji, Narges; Parvizi, Rezvan; Mosavi-Azam, Seyed Bagher

    2008-10-31

    A unicellular microalga, Chlamydomonas reinhardtii, was isolated from rice paddy-field soil and water samples and used in the biotransformation of hydrocortisone (1). This strain has not been previously tested for steroid bioconversion. Fermentation was carried out in BG-11 medium supplemented with 0.05% substrate at 25 degrees C for 14 days of incubation. The products obtained were chromatographically purified and characterized using spectroscopic methods. 11b,17 beta-Dihydroxyandrost-4-en-3-one (2), 11 beta-hydroxyandrost-4-en-3,17-dione (3), 11 beta,17 alpha,20 beta,21-tetrahydroxypregn-4-en-3-one (4) and prednisolone (5) were the main products of the bioconversion. The observed bioreaction features were the side chain degradation of the substrate to give compounds 2 and 3 and the 20-ketone reduction and 1,2-dehydrogenation affording compounds 4 and 5, respectively. A time course study showed the accumulation of product 2 from the second day of the fermentation and of compounds 3, 4 and 5 from the third day. All the metabolites reached their maximum concentration in seven days. Microalgal 18S rRNA gene was also amplified by PCR. PCR products were sequenced to confirm their authenticity as 18S rRNA gene of microalgae. The result of PCR blasted with other sequenced microalgae in NCBI showed 100% homology to the 18S small subunit rRNA of two Chlamydomonas reinhardtii spp.

  17. The lipoxygenase metabolic pathway in plants: potential for industrial production of natural green leaf volatiles

    Directory of Open Access Journals (Sweden)

    Gigot, C.

    2010-01-01

    Full Text Available Lipoxygenase enzymatic pathway is a widely studied mechanism in the plant kingdom. Combined actions of three enzymes: lipase, lipoxygenase (LOX and hydroperoxide lyase (HPL convert lipidic substrates such as C18:2 and C18:3 fatty acids into short chain volatiles. These reactions, triggered by cell membrane disruptions, produce compounds known as Green Leaf Volatiles (GLVs which are C6 or C9-aldehydes and alcohols. These GLVs are commonly used as flavors to confer a fresh green odor of vegetable to food products. Therefore, competitive biocatalytic productions have been developed to meet the high demand in these natural flavors. Vegetable oils, chosen for their lipidic acid profile, are converted by soybean LOX and plant HPL into natural GLVs. However this second step of the bioconversion presents low yield due to the HPL instability and the inhibition by its substrate. This paper will shortly describe the different enzymes involved in this bioconversion with regards to their chemical and enzymatic properties. Biotechnological techniques to enhance their production potentialities will be discussed along with their implication in a complete bioprocess, from the lipid substrate to the corresponding aldehydic or alcoholic flavors.

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

    Science.gov (United States)

    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.

  19. The modeling of ethanol production by Kluyveromyces marxianus using whey as substrate in continuous A-Stat bioreactors.

    Science.gov (United States)

    Gabardo, Sabrina; Pereira, Gabriela Feix; Rech, Rosane; Ayub, Marco Antônio Záchia

    2015-09-01

    We investigated the kinetics of whey bioconversion into ethanol by Kluyveromyces marxianus in continuous bioreactors using the "accelerostat technique" (A-stat). Cultivations using free and Ca-alginate immobilized cells were evaluated using two different acceleration rates (a). The kinetic profiles of these systems were modeled using four different unstructured models, differing in the expressions for the specific growth (μ) and substrate consumption rates (r s), taking into account substrate limitation and product inhibition. Experimental data showed that the dilution rate (D) directly affected cell physiology and metabolism. The specific growth rate followed the dilution rate (μ≈D) for the lowest acceleration rate (a = 0.0015 h(-2)), condition in which the highest ethanol yield (0.52 g g(-1)) was obtained. The highest acceleration rate (a = 0.00667 h(-2)) led to a lower ethanol yield (0.40 g g(-1)) in the system where free cells were used, whereas with immobilized cells ethanol yields increased by 23 % (0.49 g g(-1)). Among the evaluated models, Monod and Levenspiel combined with Ghose and Tyagi models were found to be more appropriate for describing the kinetics of whey bioconversion into ethanol. These results may be useful in scaling up the process for ethanol production from whey.

  20. Acute toxicity and genotoxicity of fermented traditional medicine oyaksungi-san.

    Science.gov (United States)

    Park, Hwayong; Hwang, Youn-Hwan; Ma, Jin Yeul

    2017-06-01

    The traditional medicine oyaksungi-san (OY) has been prescribed in East Asia for hundreds of years for the treatment of stroke, paralysis, and ataxia. OY also has therapeutic effects on arthralgia, myalgia, and rheumatoid arthritis, and recent studies have shown its protective effects against apoptosis of hippocampal cells and its anti-inflammatory effects on the peripheral blood cells of patient with cerebral infarction. Many studies have explored the use of traditional medicine and herb materials in the development of safe, novel, and effective pharmaceuticals with fewer side effects. These efforts commonly adopt a bioconversion tool for fermentation with beneficial microbes. However, only pharmaceuticals with high levels of safety and low levels of toxicity can be used in healthcare system. OY water extract was fermented with Lactobacillus and assayed for acute toxicity and genotoxicity. Single dose acute toxicity, bacterial reverse mutation, chromosome aberrations, and micronucleus were observed and assayed in rats, histidine/tryptophan auxotrophic bacteria, Chinese hamster ovary fibroblast cells, and mice bone marrow cells, respectively. All the experimental animals showed no abnormal behavior, clinical signs, body weight increases, or mortality. In the bacterial cultures, no revertant colonies were observed. Morphological and numerical chromosomal aberrations were not found in all metaphases examined. Frequency of induced micronuclei was not significantly increased in all doses applied. As a whole, no acute toxicity or genotoxicity were observed in all the assays examined. Therefore, fermented OY is considered to be a safe material that can be used for development of complementary and alternative medicine using bioconversion.

  1. Enhanced ethanol production from brewer's spent grain by a Fusarium oxysporum consolidated system

    Directory of Open Access Journals (Sweden)

    Christakopoulos Paul

    2009-02-01

    Full Text Available Abstract Background Brewer's spent grain (BG, a by-product of the brewing process, is attracting increasing scientific interest as a low-cost feedstock for many biotechnological applications. BG in the present study is evaluated as a substrate for lignocellulolytic enzyme production and for the production of ethanol by the mesophilic fungus Fusarium oxysporum under submerged conditions, implementing a consolidated bioconversion process. Fermentation experiments were performed with sugar mixtures simulating the carbohydrate content of BG in order to determine the utilization pattern that could be expected during the fermentation of the cellulose and hemicellulose hydrolysate of BG. The sugar mixture fermentation study focused on the effect of the initial total sugar concentration and on the effect of the aeration rate on fermenting performance of F. oxysporum. The alkali pretreatment of BG and different aeration levels during the ethanol production stage were studied for the optimization of the ethanol production by F. oxysporum. Results Enzyme yields as high as 550, 22.5, 6.5, 3225, 0.3, 1.25 and 3 U per g of carbon source of endoglucanase, cellobiohydrolase, β-D-glucosidase, xylanase, feruloyl esterase, β-D-xylosidase and α-L-arabinofuranosidase respectively, were obtained during the growth stage under optimized submerged conditions. An ethanol yield of 109 g ethanol per kg of dry BG was obtained with alkali-pretreated BG under microaerobic conditions (0.01 vvm, corresponding to 60% of the theoretical yield based on total glucose and xylose content of BG. Conclusion The enzymatic profile of the extracellular extract from F. oxysporum submerged cultures using BG and corn cob as the carbon source was proved efficient for a successful hydrolysis of BG. The fermentation study carried out using sugar mixtures simulating BG's carbohydrates content and consecutively alkali-pretreated and untreated BG, indicates that BG hydrolysis is the bottleneck

  2. Engineering a Synthetic Microbial Consortium for Comprehensive Conversion of Algae Biomass into Terpenes for Advanced Biofuels and Bioproducts

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Weihua [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Wu, Benjamin Chiau-Pin [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Davis, Ryan Wesley [Sandia National Lab. (SNL-CA), Livermore, CA (United States)

    2015-10-01

    Recent strategies for algae-based biofuels have primarily focused on biodiesel production by exploiting high algal lipid yields under nutrient stress conditions. However, under conditions supporting robust algal biomass accumulation, carbohydrate and proteins typically comprise up to ~80% of the ash-free dry weight of algae biomass. Therefore, comprehensive utilization of algal biomass for production of multipurpose intermediate- to high-value bio-based products will promote scale-up of algae production and processing to commodity volumes. Terpenes are hydrocarbon and hydrocarbon-like (C:O>10:1) compounds with high energy density, and are therefore potentially promising candidates for the next generation of value added bio-based chemicals and “drop-in” replacements for petroleum-based fuels. In this study, we demonstrated the feasibility of bioconversion of proteins into sesquiterpene compounds as well as comprehensive bioconversion of algal carbohydrates and proteins into biofuels. To achieve this, the mevalonate pathway was reconstructed into an E. coli chassis with six different terpene synthases (TSs). Strains containing the various TSs produced a spectrum of sesquiterpene compounds in minimal medium containing amino acids as the sole carbon source. The sesquiterpene production was optimized through three different regulation strategies using chamigrene synthase as an example. The highest total terpene titer reached 166 mg/L, and was achieved by applying a strategy to minimize mevalonate accumulation in vivo. The highest yields of total terpene were produced under reduced IPTG induction levels (0.25 mM), reduced induction temperature (25°C), and elevated substrate concentration (20 g/L amino acid mixture). A synthetic bioconversion consortium consisting of two engineering E. coli strains (DH1-TS and YH40-TS) with reconstructed terpene biosynthetic pathways was designed for comprehensive single-pot conversion of algal carbohydrates and proteins to

  3. Willow bioenergy plantation research in the Northeast

    Energy Technology Data Exchange (ETDEWEB)

    White, E.H.; Abrahamson, L.P.; Kopp, R.F. [SUNY College of Environmental Science and Forestry, Syracuse, NY (United States); Nowak, C.A. [USDA Forest Service, Warren, PA (United States)

    1993-12-31

    Experiments were established in Central New York in the spring of 1987 to evaluate the potential of Salix for biomass production in bioenergy plantations. Emphasis of the research was on developing and refining establishment, tending and maintenance techniques, with complimentary study of breeding, coppice physiology, pests, nutrient use and bioconversion to energy products. Current yields utilizing salix clones developed in cooperation with the University of Toronto in short-rotation intensive culture bioenergy plantations in the Northeast approximate 8 oven dry tons per acre per year with annual harvesting. Successful clones have been identified and culture techniques refined. The results are now being integrated to establish a 100 acre Salix large-scale bioenergy farm to demonstrate current successful biomass production technology and to provide plantations of sufficient size to test harvesters; adequately assess economics of the systems; and provide large quantities of uniform biomass for pilot-scale conversion facilities.

  4. Neutrophilic Iron Oxidizing Bacteria: Occurrence and Relevance in Biological Drinking Water Treatment

    DEFF Research Database (Denmark)

    Gülay, Arda; Musovic, Sanin; Albrechtsen, Hans-Jørgen

    Rapid sand filtration (RSF) is an economical way to treat anoxic groundwater around the world. It consists of groundwater aeration followed by passage through a sand filter. The oxidation and removal of ferrous iron, which is commonly found in anoxic groundwaters, is often believed to be a fully......, neutrophilic iron oxidizers were present at the level of up to 7 105 cells per gram sediment. The spatial abundance and diversity of FeOB inferred by DGGE fingerprinting differed greatly both between and within individual sand filters. The results suggest a larger than assumed role of FeOB in iron removal...... physicochemical process. However, persistently low temperatures in RSF across Denmark may negatively affect the kinetics of chemical oxidation. The slower chemical oxidation of ferrous iron may increase the chances for iron bioconversion by neutrophilic iron-oxidizing bacteria (FeOB), which are found naturally...

  5. Biodiesel production by various oleaginous microorganisms from organic wastes.

    Science.gov (United States)

    Cho, Hyun Uk; Park, Jong Moon

    2018-05-01

    Biodiesel is a biodegradable and renewable fuel. A large amount of research has considered microbial oil production using oleaginous microorganisms, but the commercialization of microbial lipids produced in this way remains uncertain due to the high cost of feedstock or low lipid yield. Microbial lipids can be typically produced by microalgae, yeasts, and bacteria; the lipid yields of these microorganisms can be improved by using sufficient concentrations of organic carbon sources. Therefore, combining low-cost organic compounds contained in organic wastes with cultivation of oleaginous microorganisms can be a promising approach to obtain commercial viability. However, to achieve effective bioconversion of low-cost substrates to microbial lipids, the characteristics of each microorganism and each substrate should be considered simultaneously. This article discusses recent approaches to developing cost-effective microbial lipid production processes that use various oleaginous microorganisms and organic wastes. Copyright © 2018 Elsevier Ltd. All rights reserved.

  6. Use of bacterial co-cultures for the efficient production of chemicals.

    Science.gov (United States)

    Jones, J Andrew; Wang, Xin

    2017-12-02

    The microbial production of chemicals has traditionally relied on a single engineered microbe to enable the complete bioconversion of substrate to final product. Recently, a growing fraction of research has transitioned towards employing a modular co-culture engineering strategy using multiple microbes growing together to facilitate a divide-and-conquer approach for chemical biosynthesis. Here, we review key success stories that leverage the unique advantages of co-culture engineering, while also addressing the critical concerns that will limit the wide-spread implementation of this technology. Future studies that address the need to monitor and control the population dynamics of each strain module, while maintaining robust flux routes towards a wide range of desired products will lead the efforts to realize the true potential of co-culture engineering. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Genome-wide Escherichia coli stress response and improved tolerance towards industrially relevant chemicals

    DEFF Research Database (Denmark)

    Rau, Martin Holm; Calero Valdayo, Patricia; Lennen, Rebecca

    2016-01-01

    Economically viable biobased production of bulk chemicals and biofuels typically requires high product titers. During microbial bioconversion this often leads to product toxicity, and tolerance is therefore a critical element in the engineering of production strains. Here, a systems biology...... approach was employed to understand the chemical stress response of Escherichia coli, including a genome-wide screen for mutants with increased fitness during chemical stress. Twelve chemicals with significant production potential were selected, consisting of organic solvent-like chemicals (butanol......, hydroxy-γ-butyrolactone, 1,4-butanediol, furfural), organic acids (acetate, itaconic acid, levulinic acid, succinic acid), amino acids (serine, threonine) and membrane-intercalating chemicals (decanoic acid, geraniol). The transcriptional response towards these chemicals revealed large overlaps...

  8. Modeling of anaerobic degradation of solid slaughterhouse waste: inhibition effects of long-chain fatty acids or ammonia.

    Science.gov (United States)

    Lokshina, L Y; Vavilin, V A; Salminen, E; Rintala, J

    2003-01-01

    The anaerobic bioconversion of solid poultry slaughterhouse wastes was kinetically investigated. The modified version of simulation model was applied for description of experimental data in mesophilic laboratory digester and assays. Additionally, stages of formation and consumption of long chain fatty acids (LCFA) were included in the model. Batch data on volatile solids, ammonium, acetate, butyrate, propionate, LCFA concentrations, pH level, cumulative volume, and methane partial pressure were used for model calibration. As a reference, the model was used to describe digestion of solid sorted household waste. Simulation results showed that an inhibition of polymer hydrolysis by volatile fatty acids and acetogenesis by NH3 or LCFA could be responsible for the complex system dynamics during degradation of lipid- and protein-rich wastes.

  9. Platform construction of molecular breeding for utilization of brown macroalgae.

    Science.gov (United States)

    Takagi, Toshiyuki; Kuroda, Kouichi; Ueda, Mitsuyoshi

    2018-01-01

    Brown macroalgae are characterized by a large size and high productivity without requiring arable land, fresh water, and fertilizer. Furthermore, since brown macroalgae contain little or no lignin, simple biorefinery processing can efficiently produce sugars from this material. Therefore, brown macroalgae have attracted attention as an alternative feedstock for bioethanol production. However, the utilization of biotechnologies previously developed for terrestrial biomass processing results in difficulties in the bioconversion of brown macroalgae. Recently, several studies have developed biotechnologies for using major carbohydrates of brown macroalgae, such as laminarin, mannitol, and alginate. This review focuses on these fermentation biotechnologies using natural or engineered microorganisms. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  10. Pharmacological evaluation and preliminary pharmacokinetics studies of a new diclofenac prodrug without gastric ulceration effect.

    Science.gov (United States)

    Santos, Jean Leandro Dos; Moreira, Vanessa; Campos, Michel Leandro; Chelucci, Rafael Consolin; Barbieri, Karina Pereira; de Castro Souto, Pollyana Cristina Maggio; Matsubara, Márcio Hideki; Teixeira, Catarina; Bosquesi, Priscila Longhin; Peccinini, Rosângela Gonçalves; Chin, Chung Man

    2012-11-19

    Long-term nonsteroidal anti-inflammatory drugs (NSAIDs) therapy has been associated with several adverse effects such as gastric ulceration and cardiovascular events. Among the molecular modifications strategies, the prodrug approach is a useful tool to discover new safe NSAIDs. The 1-(2,6-dichlorophenyl)indolin-2-one is a diclofenac prodrug which demonstrated relevant anti-inflammatory properties without gastro ulceration effect. In addition, the prodrug decreases PGE(2) levels, COX-2 expression and cellular influx into peritoneal cavity induced by carrageenan treatment. Preliminary pharmacokinetic studies have shown in vivo bioconversion of prodrug to diclofenac. This prodrug is a new nonulcerogenic NSAID useful to treat inflammatory events by long-term therapy.

  11. Pharmacological Evaluation and Preliminary Pharmacokinetics Studies of a New Diclofenac Prodrug without Gastric Ulceration Effect

    Directory of Open Access Journals (Sweden)

    Chung Man Chin

    2012-11-01

    Full Text Available Long-term nonsteroidal anti-inflammatory drugs (NSAIDs therapy has been associated with several adverse effects such as gastric ulceration and cardiovascular events. Among the molecular modifications strategies, the prodrug approach is a useful tool to discover new safe NSAIDs. The 1-(2,6-dichlorophenylindolin-2-one is a diclofenac prodrug which demonstrated relevant anti-inflammatory properties without gastro ulceration effect. In addition, the prodrug decreases PGE2 levels, COX-2 expression and cellular influx into peritoneal cavity induced by carrageenan treatment. Preliminary pharmacokinetic studies have shown in vivo bioconversion of prodrug to diclofenac. This prodrug is a new nonulcerogenic NSAID useful to treat inflammatory events by long-term therapy.

  12. Production of vanillin from waste residue of rice bran oil by Aspergillus niger and Pycnoporus cinnabarinus.

    Science.gov (United States)

    Zheng, Lirong; Zheng, Pu; Sun, Zhihao; Bai, Yanbing; Wang, Jun; Guo, Xinfu

    2007-03-01

    A new technology of transforming ferulic acid, which was from waste residue of rice bran oil, into vanillin was developed by a combination of fungal strains Aspergillus niger CGMCC0774 and Pycnoporus cinnabarinus CGMCC1115. Various concentrations of ferulic acid were compared, and the highest yield reached 2.2 g l(-1) of vanillic acid by A. niger CGMCC0774 in a 25 l fermenter when concentration of ferulic acid was 4 g l(-1). The filtrate of A. niger CGMCC0774 culture was concentrated and vanillic acid in the filtrate was bio-converted into vanillin by P. cinnabarinus CGMCC1115. The yield of vanillin reached 2.8 g l(-1) when 5 g l(-1) of glucose and 25 g of HZ802 resin were supplemented in the bioconversion medium. The 13C isotope analysis indicated that delta13C(PDB) of vanillin prepared was much different from chemically synthesized vanillin.

  13. Selection of Co-Substrate and Aeration Conditions for Vanillin Production by Escherichia coli JM109/pBB1

    Directory of Open Access Journals (Sweden)

    Paolo Torre

    2004-01-01

    Full Text Available Yeast extract, Luria-Bertani medium and tryptone were tested as co-substrates for vanillin production from ferulic acid by resting cells of Escherichia coli JM109/pBB1. Yeast extract proved to be the best component for sustaining such a bioconversion, which is not self-sustained from the bioenergetic point of view. Tests were also performed under variable aeration conditions by simultaneously varying the ratio of medium to vessel volume and the agitation speed. The results of these tests suggest that, under excess aeration, a non-specific oxidase activity was very likely responsible for the oxidation of a significant portion of vanillin to vanillic acid, thus reducing the vanillin yield.

  14. Novel strategy to improve vanillin tolerance and ethanol fermentation performances of Saccharomycere cerevisiae strains.

    Science.gov (United States)

    Zheng, Dao-Qiong; Jin, Xin-Na; Zhang, Ke; Fang, Ya-Hong; Wu, Xue-Chang

    2017-05-01

    The aim of this work was to develop a novel strategy for improving the vanillin tolerance and ethanol fermentation performances of Saccharomyces cerevisiae strains. Isogeneic diploid, triploid, and tetraploid S. cerevisiae strains were generated by genome duplication of haploid strain CEN.PK2-1C. Ploidy increments improved vanillin tolerance and diminished proliferation capability. Antimitotic drug methyl benzimidazol-2-ylcarbamate (MBC) was used to introduce chromosomal aberrations into the tetraploid S. cerevisiae strain. Interestingly, aneuploid mutants with DNA contents between triploid and tetraploid were more resistant to vanillin and showed faster ethanol fermentation rates than all euploid strains. The physiological characteristics of these mutants suggest that higher bioconversion capacities of vanillin and ergosterol contents might contribute to improved vanillin tolerance. This study demonstrates that genome duplication and MBC treatment is a powerful strategy to improve the vanillin tolerance of yeast strains. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Rational design of Bacillus stearothermophilus US100 L-arabinose isomerase: potential applications for D-tagatose production.

    Science.gov (United States)

    Rhimi, Moez; Aghajari, Nushin; Juy, Michel; Chouayekh, Hichem; Maguin, Emmanuelle; Haser, Richard; Bejar, Samir

    2009-05-01

    L-arabinose isomerases catalyze the bioconversion of D-galactose into D-tagatose. With the aim of producing an enzyme optimized for D-tagatose production, three Bacillus stearothermophilus US100 L-arabinose isomerase mutants were constructed, purified and characterized. Our results indicate that mutant Q268K was significantly more acidotolerant and more stable at acidic pH than the wild-type enzyme. The N175H mutant has a broad optimal temperature range from 50 to 65 degrees C. With the aim of constructing an acidotolerant mutant working at relatively low temperatures we generated the Q268K/N175H construct. This double mutant displays an optimal pH in the range 6.0-7.0 and an optimal activity around 50-65 degrees C, temperatures at which the enzyme was stable without addition of metal ions.

  16. Solar Energy: Its Technologies and Applications

    Science.gov (United States)

    Auh, P. C.

    1978-06-01

    Solar heat, as a potential source of clean energy, is available to all of us. Extensive R and D efforts are being made to effectively utilize this renewable energy source. A variety of different technologies for utilizing solar energy have been proven to be technically feasible. Here, some of the most promising technologies and their applications are briefly described. These are: Solar Heating and Cooling of Buildings (SHACOB), Solar Thermal Energy Conversion (STC), Wind Energy Conversion (WECS), Bioconversion to Fuels (BCF), Ocean Thermal Energy Conversion (OTEC), and Photovoltaic Electric Power Systems (PEPS). Special emphasis is placed on the discussion of the SHACOB technologies, since the technologies are being expeditiously developed for the near commercialization.

  17. Energy, water and climate nexus: A case study of Cameroon

    DEFF Research Database (Denmark)

    Ackom, Emmanuel

    2014-01-01

    potential to offset the reliance on crude oil. This study investigated the biomass resource availability from agricultural residues for liquid biofuel (as transportation fuel) and bioelectricity. Our findings indicate that sustainably extracted agricultural re sidues could yield 1.11 million bone dry tons...... per year. Using current bioconversion efficiency rates, the residues could potentially yield 0.12-0.32 billion liters of ethanol annually that is enough to offset 18-48% of the national consumption of gasoline. For bioelectricity generation, the same residues could provide 0.76-2.02 TW h, or 15...... of agricultural residues. The study provides policy recommendations to help encourage modern bioenergy applications from residues in Cameroon....

  18. Optimization of upstream and development of cellulose hydrolysis process for cellulosic bio-ethanol production

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Hyun Jong; Wi, Seung Gon; Kim, Su Bae; Shin, You Jung; Yi, Ju Hui [Chonnam National University, Bio-Energy Research Institute, Gwangju (Korea, Republic of)

    2010-10-15

    The purpose of this project is optimization of upstream and development of cellulose hydrolysis process for cellulosic bio-ethanol production. Research scope includes 1) screening of various microorganisms from decayed biomass in order to search for more efficient lignocellulose degrading microorganism, 2) identification and verification of new cell wall degrading cellulase for application cellulose bioconversion process, and 3) identification and characterization of novel genes involved in cellulose degradation. To find good microorganism candidates for lignocellulose degrading, 75 decayed samples from different areas were assayed in triplicate and analyzed. For cloning new cell wall degrading enzymes, we selected microorganisms because it have very good lignocellulose degradation ability. From that microorganisms, we have apparently cloned a new cellulase genes (10 genes). We are applying the new cloned cellulase genes to characterize in lignocellulsoe degradation that are most important to cellulosic biofuels production

  19. Comparison of Ultrasonic and CO2 Laser Pretreatment Methods on Enzyme Digestibility of Corn Stover

    Directory of Open Access Journals (Sweden)

    Li-Li Zuo

    2012-03-01

    Full Text Available To decrease the cost of bioethanol production, biomass recalcitrance needs to be overcome so that the conversion of biomass to bioethanol becomes more efficient. CO2 laser irradiation can disrupt the lignocellulosic physical structure and reduce the average size of fiber. Analyses with Fourier transform infrared spectroscopy, specific surface area, and the microstructure of corn stover were used to elucidate the enhancement mechanism of the pretreatment process by CO2 laser irradiation. The present work demonstrated that the CO2 laser had potential to enhance the bioconversion efficiency of lignocellulosic waste to renewable bioethanol. The saccharification rate of the CO2 laser pretreatment was significantly higher than ultrasonic pretreatment, and reached 27.75% which was 1.34-fold of that of ultrasonic pretreatment. The results showed the impact of CO2 laser pretreatment on corn stover to be more effective than ultrasonic pretreatment.

  20. Systems analysis for the development of small resource recovery systems: system performance data. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Crnkovich, P G; Helmstetter, A J

    1980-10-01

    The technologies that should be developed to make small-scale solid waste processing facilities attractive and viable for small municipalities with solid waste between 50 and 250 tons per day are identified. The resource recovery systems investigated were divided into three categories: thermal processng, mechanical separation, and biological processing. Thermal processing systems investigated are: excess-air incineration; starved-air incineration/gasification; and pyrolysis (indirect heating). Mechanical processing systems investigated are: coarse refuse derived fuel; materials separation; dust refuse derived fuel; densified refuse derived fuel; and fine refuse derived fuel. Mechanical processing components investigated include: receiving module; primary size reduction module; combustible separation module; refuse derived fuel preparation module; fuel densification; fuel storage module; ferrous separation; and building and facilities. Pretreatment processes and principle methods of bioconversion of MSW dealing with biological processing are investigated. (MCW)

  1. Lactobacillus acidophilus Metabolizes Dietary Plant Glucosides and Externalizes Their Bioactive Phytochemicals

    DEFF Research Database (Denmark)

    Theilmann, Mia Christine; Goh, Yong Jun; Nielsen, Kristian Fog

    2017-01-01

    Therapeutically active glycosylated phytochemicals are ubiquitous in the human diet. The human gut microbiota (HGM) modulates the bioactivities of these compounds, which consequently affect host physiology and microbiota composition. Despite a significant impact on human health, the key players...... of the loci to distinct groups of PGs. Following intracellular deglucosylation, the aglycones of PGs are externalized, rendering them available for absorption by the host or for further modification by other microbiota taxa. The PG utilization loci are conserved in L. acidophilus and closely related...... active plant-derived compounds are widely present in berries, fruits, nuts, and beverages like tea and wine. The bioactivity and bioavailability of these compounds, which are typically glycosylated, are altered by microbial bioconversions in the human gut. Remarkably, little is known about...

  2. Methane recovery from animal manures: A current opportunities casebook

    Energy Technology Data Exchange (ETDEWEB)

    Lusk, P. [Resource Development Associates, Marietta, GA (United States)

    1994-12-01

    One manure management system provides not only pollution prevention but also converts a manure management problem into a new profit center. Economic evaluations and case studies of operating systems indicate that the anaerobic digestion of livestock manures is a commercially-available bioconversion technology with considerable potential for providing profitable co-products including a cost-effective renewable fuel for livestock production operations. This Casebook examines some of the current opportunities for the recovery of methane from the anaerobic digestion of animal manures. The economic evaluations are based on engineering studies of digesters that generate electricity from the recovered methane. Regression models, which can be used to estimate digester cost and internal rate of return, are developed from the evaluations. Finally, anaerobic digestion has considerable potential beyond agribusiness. Examples of digesters currently employed by other industries are provided.

  3. Enzymatic approaches to rare sugar production.

    Science.gov (United States)

    Zhang, Wenli; Zhang, Tao; Jiang, Bo; Mu, Wanmeng

    Rare sugars have recently attracted much attention because of their potential applications in the food, nutraceutical, and pharmaceutical industries. A systematic strategy for enzymatic production of rare sugars, named Izumoring, was developed >10years ago. The strategy consists of aldose-ketose isomerization, ketose C-3 epimerization, and monosaccharide oxidation-reduction. Recent development of the Izumoring strategy is reviewed herein, especially the genetic approaches to the improvement of rare sugar-producing enzymes and the applications of target-oriented bioconversion. In addition, novel non-Izumoring enzymatic approaches are also summarized, including enzymatic condensation, phosphorylation-dephosphorylation cascade reaction, aldose epimerization, ulosonic acid decarboxylation, and biosynthesis of rare disaccharides. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Biocatalytic production of D-tagatose: A potential rare sugar with versatile applications.

    Science.gov (United States)

    Jayamuthunagai, J; Gautam, P; Srisowmeya, G; Chakravarthy, M

    2017-11-02

    D-tagatose is a naturally existing rare monosaccharide having prebiotic properties. Minimal absorption, low metabolizing energy, and unique clinical properties are the characteristics of D-tagatose. D-tagatose gained international attention by matching the purpose of alternate sweeteners that is much needed for the control of diabetes among world population. Recent efforts in understanding tagatose bioconversion have generated essential information regarding its production and application. This article reviews the evolution of D-tagatose as an important rare sugar by appreciable improvements in production results and its significant applications resulted of its unique physical, chemical, biological, and clinical properties thus considering it an appropriate product for requisite improvements in technical viability. Based on current knowledge and technology projections, the commercialization of D-tagatose rare sugar as food additive is close to reality.

  5. Extrusion Pretreatment of Lignocellulosic Biomass: A Review

    Directory of Open Access Journals (Sweden)

    Jun Zheng

    2014-10-01

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

  6. Bioactive assessment of selected marine red algae against leishmania major and chemical constituents of osmundea pinnatifida

    International Nuclear Information System (INIS)

    Haq, T.; Khan, F.A.; Begum, R.; Munshi, A.B.

    2011-01-01

    Present bioconversion studies were carried out to convert drifted seaweed biomass into bioactive organic compost. Chemical analysis of the collected seaweed biomass from the Karachi coast revealed 60.30 % organic matter. Aerobic composting method i.e., windrow composting technique was applied for the conversion of collected seaweed biomass into organic compost. Employing this technique almost 70% biomass was converted into organic compost. On analysis, the compost obtained by the above method showed 2.3% Nitrogen, 0.86% Phosphate and 1.8% Potassium. Results for the analysis of heavy metals showed Mercury 0.05 mg / kg, Arsenic BDL Cadmium 0.080 mg / kg and Copper 7.1 mg / kg. Results for the biological evaluation of seaweed compost showed 78% germabilty while the Biogold and cow dung showed 83 and 60% germabilty. (author)

  7. Advances in the enzymatic production of L-hexoses.

    Science.gov (United States)

    Chen, Ziwei; Zhang, Wenli; Zhang, Tao; Jiang, Bo; Mu, Wanmeng

    2016-08-01

    Rare sugars have recently drawn attention because of their potential applications and huge market demands in the food and pharmaceutical industries. All L-hexoses are considered rare sugars, as they rarely occur in nature and are thus very expensive. L-Hexoses are important components of biologically relevant compounds as well as being used as precursors for certain pharmaceutical drugs and thus play an important role in the pharmaceutical industry. Many general strategies have been established for the synthesis of L-hexoses; however, the only one used in the biotechnology industry is the Izumoring strategy. In hexose Izumoring, four entrances link the D- to L-enantiomers, ketose 3-epimerases catalyze the C-3 epimerization of L-ketohexoses, and aldose isomerases catalyze the specific bioconversion of L-ketohexoses and the corresponding L-aldohexoses. In this article, recent studies on the enzymatic production of various L-hexoses are reviewed based on the Izumoring strategy.

  8. Chemical products and industrial materials

    International Nuclear Information System (INIS)

    1995-12-01

    A compilation of all universities, industrial and governmental agencies in Quebec which are actively involved in research and development of chemical products and industrial materials derived from biomass products, was presented. Each entry presented in a standard format that included a description of the major research activities of the university or agency, the principal technologies used in the research, available research and analytical equipment, a description of the research personnel, names, and addresses of contact persons for the agency or university. Thirty entries were presented. These covered a wide diversity of activities including biotechnological research such as genetic manipulations, bioconversion, fermentation, enzymatic hydrolysis and physico-chemical applications such as bleaching, de-inking, purification and synthesis. tabs

  9. Plant-microbe genomic systems optimization for energy

    Energy Technology Data Exchange (ETDEWEB)

    Hazen, Samuel P. [Univ. of Massachusetts, Amherst, MA (United States)

    2017-12-20

    The overall objective of this project was to identify genetic variation within grasses that results in increased biomass yield and biofuel conversion efficiency. Improving energy crops hinges on identifying the genetic mechanisms underlying traits that benefit energy production. The exploitation of natural variation in plant species is an ideal approach to identify both the traits and the genes of interest in the production of biofuels. The specific goals of this project were to (1) quantify relevant genetic diversity for biofuel feedstock bioconversion efficiency and biomass accumulation, (2) identify genetic loci that control these traits, and (3) characterize genes for improved energy crop systems. Determining the key genetic contributors influencing biofuel traits is required in order to determine the viability of these traits as targets for improvement; only then will we be able to apply modern breeding practices and genetic engineering for the rapid improvement of feedstocks.

  10. Perspectives for the production of bioethanol from lignocellulosic materials

    International Nuclear Information System (INIS)

    Petrova, Petia; Ivanova, Viara

    2010-01-01

    The most common renewable fuel today and suitable alternative to replace fossil fuels is ethanol that can be blended with petrol or used as neat alcohol in engines. Ethanol is currently produced from sugar (Brazil) or grain (starch, USA). However, this raw material base will not be sufficient because the increasing demand for fuel ethanol and the lower than expected reduction of greenhouse gases. An alternative is the production of bioethanol from agroindustrial wastes containing abundant cellulose fibers and carbohydrates such as grape pomace, sugar beet pomace, barley and rice straw, corncobs, sunflower stalks and heads, cotton waste, brewer's spent grain, forest residues etc. Lignocellulosic raw materials and agroindustrial wastes minimize the potential conflict between land use for food (and feed) production and energy feedstock production. This review summarizes recent developments in the bioconversion processes, the new technologies required and the advances achieved in recent years to bring agricultural feedstock and lignocellulosic ethanol towards industrial production.

  11. Value-added biotransformation of cellulosic sugars by engineered Saccharomyces cerevisiae.

    Science.gov (United States)

    Lane, Stephan; Dong, Jia; Jin, Yong-Su

    2018-07-01

    The substantial research efforts into lignocellulosic biofuels have generated an abundance of valuable knowledge and technologies for metabolic engineering. In particular, these investments have led to a vast growth in proficiency of engineering the yeast Saccharomyces cerevisiae for consuming lignocellulosic sugars, enabling the simultaneous assimilation of multiple carbon sources, and producing a large variety of value-added products by introduction of heterologous metabolic pathways. While microbial conversion of cellulosic sugars into large-volume low-value biofuels is not currently economically feasible, there may still be opportunities to produce other value-added chemicals as regulation of cellulosic sugar metabolism is quite different from glucose metabolism. This review summarizes these recent advances with an emphasis on employing engineered yeast for the bioconversion of lignocellulosic sugars into a variety of non-ethanol value-added products. Copyright © 2018 Elsevier Ltd. All rights reserved.

  12. Vitamin E in human skin: organ-specific physiology and considerations for its use in dermatology.

    Science.gov (United States)

    Thiele, Jens J; Ekanayake-Mudiyanselage, Swarna

    2007-01-01

    Vitamin E has been used for more than 50 years in experimental and clinical dermatology. While a large number of case reports were published in this time, there is still a lack of controlled clinical studies providing a rationale for well defined dosages and clinical indications. In contrast, advances in basic research on the physiology, mechanism of action, penetration, bioconversion and photoprotection of vitamin E in human skin has led to the development of numerous new formulations for use in cosmetics and skin care products. This article reviews basic mechanisms and possible cosmetic as well as clinical implications of the recent advances in cutaneous vitamin E research. Experimental evidence suggests that topical and oral vitamin E has antitumorigenic, photoprotective, and skin barrier stabilizing properties. While the current use of vitamin E is largely limited to cosmetics, controlled clinical studies for indications such as atopic dermatitis or preventions of photocarcinogenesis are needed to evaluate the clinical benefit of vitamin E.

  13. An integrated model for the technical and economic evaluation of an enzymatic biomass conversion process

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Q A; Saddler, J N [Forintek Canada Corp., Ottawa, Ontario (CA). Dept. of Biotechnology and Chemistry

    1991-01-01

    A process simulation model was constructed, using the Lotus 123 spreadsheet, to evaluate the technical and economic feasibility of a lignocellulosic-to-ethanol bioconversion process. The major components of the process were: steam pretreatment, fractionation, enzyme production, enzymatic hydrolysis, ethanol fermentation of glucose and xylose, product recovery, and waste treatment. The model provided an estimation of the price of ethanol and evaluated the interdependence of process parameters and their effect on the production cost of ethanol. A case study of a plant processing 500 tonnes of aspenwood per day showed that the parameters which had the most significant impact on the price of ethanol were: the cost of wood, cost of enzymes, efficiency of cellulose hydrolysis, ethanol yield from xylose, efficiency of the fractionation process, and the selling price of the lignin by-product. (author).

  14. High-yield production of mannitol by Leuconostoc pseudomesenteroides CTCC G123 from chicory-derived inulin hydrolysate.

    Science.gov (United States)

    Zhang, Min; Gu, Lei; Cheng, Chao; Zhu, Junru; Wu, Hao; Ma, Jiangfeng; Dong, Weiliang; Kong, Xiangping; Jiang, Min; Ouyang, Pingkai

    2017-08-01

    Chicory is an agricultural plant with considerable potential as a carbohydrate substrate for low-cost production of biochemicals. In this work, the production of mannitol by Leuconostoc pseudomesenteroides CTCC G123 from chicory-derived inulin hydrolysate was investigated. The bioconversion process initially suffered from the leakage of fructose to the phosphoketolase pathway, resulting in a low mannitol yield. When inulin hydrolysate was supplemented with glucose as a substrate for mannitol production in combination with aeration induction and nicotinic acid induced redox modulation strategies, the mannitol yield greatly improved. Under these conditions, significant improvement in the glucose consumption rate, intracellular NADH levels and mannitol dehydrogenase specific activity were observed, with mannitol production increasing from 64.6 to 88.1 g/L and overall yield increase from 0.69 to 0.94 g/g. This work demonstrated an efficient method for the production of mannitol from inulin hydrolysate with a high overall yield.

  15. Multi-scale process and supply chain modelling: from lignocellulosic feedstock to process and products.

    Science.gov (United States)

    Hosseini, Seyed Ali; Shah, Nilay

    2011-04-06

    There is a large body of literature regarding the choice and optimization of different processes for converting feedstock to bioethanol and bio-commodities; moreover, there has been some reasonable technological development in bioconversion methods over the past decade. However, the eventual cost and other important metrics relating to sustainability of biofuel production will be determined not only by the performance of the conversion process, but also by the performance of the entire supply chain from feedstock production to consumption. Moreover, in order to ensure world-class biorefinery performance, both the network and the individual components must be designed appropriately, and allocation of resources over the resulting infrastructure must effectively be performed. The goal of this work is to describe the key challenges in bioenergy supply chain modelling and then to develop a framework and methodology to show how multi-scale modelling can pave the way to answer holistic supply chain questions, such as the prospects for second generation bioenergy crops.

  16. Dry fractionation process as an important step in current and future lignocellulose biorefineries: a review.

    Science.gov (United States)

    Barakat, Abdellatif; de Vries, Hugo; Rouau, Xavier

    2013-04-01

    The use of lignocellulosic biomass is promising for biofuels and materials and new technologies for the conversion need to be developed. However, the inherent properties of native lignocellulosic materials make them resistant to enzymatic and chemical degradation. Lignocellulosic biomass requires being pretreated to change the physical and chemical properties of lignocellulosic matrix in order to increase cell wall polymers accessibility and bioavailability. Mechanical size reduction may be chemical free intensive operation thanks to decreasing particles size and cellulose crystallinity, and increasing accessible surface area. Changes in these parameters improve the digestibility and the bioconversion of lignocellulosic biomass. However, mechanical size reduction requires cost-effective approaches from an energy input point of view. Therefore, the energy consumption in relation to physicochemical properties of lignocellulosic biomass was discussed. Even more, chemical treatments combined with physicochemical size reduction approaches are proposed to reduce energy consumption in this review. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Biotransformation of artemisinin using cell suspension cultures of Catharanthus roseus (L.) G.Don and Lavandula officinalis L.

    Science.gov (United States)

    Patel, Suman; Gaur, Rashmi; Verma, Priyanka; Bhakuni, Rajendra S; Mathur, Archana

    2010-08-01

    Artemisinin, an antimalarial compound, at 5 mg/40 ml, was transformed by cell suspension cultures of Catharanthus roseus (L.) G.Don and Lavandula officinalis L. into deoxyartemisinin with yields >78% (3.93 mg deoxyartemisinin from 5 mg artemisinin). Maximum conversion (78.6 and 78%) occurred after 6 and 7 days of adding artemisinin to 20 and 9 days old cultures of C. roseus and L. officinalis, respectively. The procedure was scaled up by and 500 mg artemisinin was transformed into 390 mg deoxyartemisinin. Addition of artemisinin at the beginning of the culture cycle resulted in >50% reduction in dry biomass production with no bioconversion. Conversion of artemisinin occurred intracellularly followed by leaching of the product into the medium.

  18. Steam explosion pretreatment for enhancing biogas production of late harvested hay.

    Science.gov (United States)

    Bauer, Alexander; Lizasoain, Javier; Theuretzbacher, Franz; Agger, Jane W; Rincón, María; Menardo, Simona; Saylor, Molly K; Enguídanos, Ramón; Nielsen, Paal J; Potthast, Antje; Zweckmair, Thomas; Gronauer, Andreas; Horn, Svein J

    2014-08-01

    Grasslands are often abandoned due to lack of profitability. Extensively cultivating grassland for utilization in a biogas-based biorefinery concept could mend this problem. Efficient bioconversion of this lignocellulosic biomass requires a pretreatment step. In this study the effect of different steam explosion conditions on hay digestibility have been investigated. Increasing severity in the pretreatment induced degradation of the hemicellulose, which at the same time led to the production of inhibitors and formation of pseudo-lignin. Enzymatic hydrolysis showed that the maximum glucose yields were obtained under pretreatment at 220 °C for 15 min, while higher xylose yields were obtained at 175 °C for 10 min. Pretreatment of hay by steam explosion enhanced 15.9% the methane yield in comparison to the untreated hay. Results indicate that hay can be effectively converted to methane after steam explosion pretreatment. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Fungal Strains as Catalysts for the Biotransformation of Halolactones by Hydrolytic Dehalogenation with the Dimethylcyclohexane System

    Directory of Open Access Journals (Sweden)

    Małgorzata Grabarczyk

    2012-08-01

    Full Text Available Bicyclic chloro-, bromo- and iodo-γ-lactones with dimethylcyclohexane rings were used as substrates for bioconversion by several fungal strains (Fusarium, Botrytis and Beauveria. Most of the selected microorganisms transformed these lactones by hydrolytic dehalogenation into the new compound cis-2-hydroxy-4,6-dimethyl-9-oxabicyclo[4.3.0]- nonan-8-one, mainly the (−-isomer. When iodo-γ-lactone was used as the substrate, two products were observed: a hydroxy-γ-lactone and an unsaturated lactone. The structures of all substrates and products were established on the basis of their spectral data. The mechanism of dehalogenation of three halolactones was also studied.

  20. Coal liquefaction: A research and development needs assessment: Final report, Volume II

    Energy Technology Data Exchange (ETDEWEB)

    Schindler, H.D.; Burke, F.P.; Chao, K.C.; Davis, B.H.; Gorbaty, M.L.; Klier, K.; Kruse, C.W.; Larsen, J.W.; Lumpkin, R.E.; McIlwain, M.E.; Wender, I.; Stewart, N.

    1989-03-01

    Volume II of this report on an assessment of research needs for coal liquefaction contains reviews of the five liquefaction technologies---direct, indirect, pyrolysis, coprocessing, and bioconversion. These reviews are not meant to be encyclopedic; several outstanding reviews of liquefaction have appeared in recent years and the reader is referred to these whenever applicable. Instead, these chapters contain reviews of selected topics that serve to support the panel's recommendations or to illustrate recent accomplishments, work in progress, or areas of major research interest. At the beginning of each of these chapters is a brief introduction and a summary of the most important research recommendations brought out during the panel discussions and supported by the material presented in the review. A review of liquefaction developments outside the US is included. 594 refs., 100 figs., 60 tabs.

  1. Biorefineries of carbon dioxide: From carbon capture and storage (CCS) to bioenergies production.

    Science.gov (United States)

    Cheah, Wai Yan; Ling, Tau Chuan; Juan, Joon Ching; Lee, Duu-Jong; Chang, Jo-Shu; Show, Pau Loke

    2016-09-01

    Greenhouse gas emissions have several adverse environmental effects, like pollution and climate change. Currently applied carbon capture and storage (CCS) methods are not cost effective and have not been proven safe for long term sequestration. Another attractive approach is CO2 valorization, whereby CO2 can be captured in the form of biomass via photosynthesis and is subsequently converted into various form of bioenergy. This article summarizes the current carbon sequestration and utilization technologies, while emphasizing the value of bioconversion of CO2. In particular, CO2 sequestration by terrestrial plants, microalgae and other microorganisms are discussed. Prospects and challenges for CO2 conversion are addressed. The aim of this review is to provide comprehensive knowledge and updated information on the current advances in biological CO2 sequestration and valorization, which are essential if this approach is to achieve environmental sustainability and economic feasibility. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Nitrile-converting enzymes as a tool to improve biocatalysis in organic synthesis: recent insights and promises.

    Science.gov (United States)

    Gong, Jin-Song; Shi, Jin-Song; Lu, Zhen-Ming; Li, Heng; Zhou, Zhe-Min; Xu, Zheng-Hong

    2017-02-01

    Nitrile-converting enzymes, including nitrilase and nitrile hydratase (NHase), have received increasing attention from researchers of industrial biocatalysis because of their critical role as a tool in organic synthesis of carboxylic acids and amides from nitriles. To date, these bioconversion approaches are considered as one of the most potential industrial processes using resting cells or purified enzymes as catalysts for production of food additives, pharmaceutical, and agrochemical precursors. This review focuses on the distribution and catalytic mechanism research of nitrile-converting enzymes in recent years. Molecular biology aspects to improve the biocatalytic performance of microbial nitrilase and NHase are demonstrated. The process developments of microbial nitrilase and NHase for organic synthesis are also discussed.

  3. Overproduction of cellulase by Trichoderma reesei RUT C30 through batch-feeding of synthesized low-cost sugar mixture.

    Science.gov (United States)

    Li, Yonghao; Liu, Chenguang; Bai, Fengwu; Zhao, Xinqing

    2016-09-01

    Cellulase is a prerequisite for the bioconversion of lignocellulosic biomass, but its high cost presents the biggest challenge. In this article, low-cost mixture was produced from glucose through the transglycosylation reaction catalyzed by β-glucosidase for cellulase overproduction by Trichodema reesei RUT C30. As a result, cellulase titer of 90.3FPU/mL, which was more than 10 folds of that achieved with lactose as inducer, was achieved at 144h. Meanwhile, cellulase productivity was drastically increased to 627.1FPU/L/h, at least 3-5 folds higher than previously reported by the fungal species. The crude enzyme was further tested by hydrolyzing NaOH-pretreated corn stover with 15% solid loading, and 96.6g/L glucose was released with 92.6% sugar yield at 96h and 44.8g/L ethanol was obtained. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Xylanase production by Trichoderma longibrachiatum

    Energy Technology Data Exchange (ETDEWEB)

    Royer, J C; Nakas, J P [State Univ. of New York, Syracuse, NY (USA). Coll. of Environmental Science and Forestry

    1989-07-01

    Xylan comprises up to 25% of hardwood biomass and is found in a variety of agricultural residues. It therefore represents a significant renewable resource which should be utilized to improve the economics of bioconversion of plant biomass to useful products. Before fermentation to fuels or solvents, xylan must be hydrolysed to xylose or short-chain oligomers of xylose. The effects of carbon source, substrate concentration, culture pH, and spore inoculum concentration on production of extracellular xylanase and cellulase were examined. Very low enzyme activities were obtained with growth on glucose, xylose, and cellobiose, while significantly higher levels were produced from lactose and arabinose. Higher levels of both enzymes were generated from alpha cellulose, wood pulp, and fibrous paper waste than from purified xylan. (author).

  5. Comparative biodegradation of alkyl halide insecticides by the white rot fungus, Phanerochaete chrysosporium (BKM-F-1767)

    International Nuclear Information System (INIS)

    Kennedy, D.W.; Aust, S.D.; Bumpus, J.A.

    1990-01-01

    The ability of Phanerochaete chrysosporium to degrade six alkyl halide insecticides (aldrin, dieldrin, heptachlor, chlordane, lindane, and mirex) in liquid and soil-corncob matrices was compared by using 14 C-labeled compounds. Of these, only [ 14 C]lindane and [ 14 C]chlordane underwent extensive biodegradation, as evidenced by the fact that 9.4 to 23.4% of these compounds were degraded to 14 CO 2 in 30 days in liquid cultures and 60 days in soil-corncob cultures inoculated with P. chrysosporium. Although [ 14 C]aldrin, [ 14 C]dieldrin, [ 14 C]heptachlor, and [14D]mirex were poorly mineralized, substantial bioconversion occurred, as determined by substrate disappearance and metabolite formation. Nonbiological disappearance was observed only with chlordane and heptachlor

  6. Energy from plants: problems and prospects

    Energy Technology Data Exchange (ETDEWEB)

    Khoshoo, T.N.

    1982-01-01

    This article contains the presidential address to the Section of Botany (VI). After an introduction and a brief account of the process and efficiency of photosynthesis, the address describes terrestrial and aquatic biomass, biological hydrogen production and bioconversion (the conversion of biomass and organic wastes into energy and also into fertilizers, food and chemicals). The section on terrestial biomass is with particular reference to India and examines fuel plantations, the possibility of covered energy farms (such as the growth of alfalfa in greenhouses), the production of agricultural alcohol, the use of vegetable oils as fuel, the production and use of jojoba (Simmondsia chinensis) wax, and hydrocarbon producing plants (rubber, Euphorbia spp., various Leguminosae etc.).

  7. Relationship between fiber porosity and cellulose digestibility in steam-exploded Pinus radiata

    Energy Technology Data Exchange (ETDEWEB)

    Wong, K.K.Y.; Deverell, K.F.; Mackie, K.L.; Clark, T.A.; Donaldson, L.A.

    1988-04-05

    The use of lignocellulosic materials in bioconversion processes may be improved if the critical factors limiting conversion are better understood. Steam explosion after sulfur dioxide impregnation of wood chips is an effective method for improving the enzymatic digestibility of cellulose in the softwood Pinus radiata. Digestibility of pretreated fiber was progressively increased by altering the conditions of steam explosion. With increasing digestibility, there was an observed increase in fiber porosity as measured by the solute exclusion technique. Accessible pore volume and accessible surface area to a 5-nm dextran probe positively correlated with both 2- and 24-h digestion yields from pretreated fiber. The increase in accessibility was probably the result of hemicellulose extraction and lignin redistribution. A subsequent loss in accessibility, brought about by structural collapse or further lignin redistribution, resulted in a corresponding loss in digestibility. It appears that steam explosion increases cellulose digestibility in P. radiata by increasing fiber porosity.

  8. Effect of SBR feeding strategy and feed composition on the stability of aerobic granular sludge in the treatment of a simulated textile wastewater.

    Science.gov (United States)

    Franca, R D G; Ortigueira, J; Pinheiro, H M; Lourenço, N D

    2017-09-01

    Treatment of the highly polluting and variable textile industry wastewater using aerobic granular sludge (AGS) sequencing batch reactors (SBRs) has been recently suggested. Aiming to develop this technology application, two feeding strategies were compared regarding the capacity of anaerobic-aerobic SBRs to deal with disturbances in the composition of the simulated textile wastewater feed. Both a statically fed, anaerobic-aerobic SBR and an anaerobic plug-flow fed, anaerobic-aerobic SBR could cope with shocks of high azo dye concentration and organic load, the overall chemical oxygen demand and color removal yields being rapidly restored to 80%. Yet, subsequent azo dye metabolite bioconversion was not observed, along the 315-day run. Moreover, switching from a starch-based substrate to acetate in the feed composition deteriorated AGS stability. Overall, the plug-flow fed SBR recovered more rapidly from the imposed disturbances. Further research is needed towards guaranteeing long-term AGS stability during the treatment of textile wastewater.

  9. Integrated biogas upgrading and hydrogen utilization in an anaerobic reactor containing enriched hydrogenotrophic methanogenic culture

    DEFF Research Database (Denmark)

    Luo, Gang; Angelidaki, Irini

    2012-01-01

    Biogas produced by anaerobic digestion, is mainly used in a gas motor for heat and electricity production. However, after removal of CO2, biogas can be upgraded to natural gas quality, giving more utilization possibilities, such as utilization as autogas, or distant utilization by using...... the existing natural gas grid. The current study presents a new biological method for biogas upgrading in a separate biogas reactor, containing enriched hydrogenotrophic methanogens and fed with biogas and hydrogen. Both mesophilic- and thermophilic anaerobic cultures were enriched to convert CO2 to CH4...... by addition of H2. Enrichment at thermophilic temperature (55°C) resulted in CO2 and H2 bioconversion rate of 320 mL CH4/(gVSS h), which was more than 60% higher than that under mesophilic temperature (37°C). Different dominant species were found at mesophilic- and thermophilic-enriched cultures, as revealed...

  10. METABOLIC MODELLING IN THE DEVELOPMENT OF CELL FACTORIES BY SYNTHETIC BIOLOGY

    Directory of Open Access Journals (Sweden)

    Paula Jouhten

    2012-10-01

    Full Text Available Cell factories are commonly microbial organisms utilized for bioconversion of renewable resources to bulk or high value chemicals. Introduction of novel production pathways in chassis strains is the core of the development of cell factories by synthetic biology. Synthetic biology aims to create novel biological functions and systems not found in nature by combining biology with engineering. The workflow of the development of novel cell factories with synthetic biology is ideally linear which will be attainable with the quantitative engineering approach, high-quality predictive models, and libraries of well-characterized parts. Different types of metabolic models, mathematical representations of metabolism and its components, enzymes and metabolites, are useful in particular phases of the synthetic biology workflow. In this minireview, the role of metabolic modelling in synthetic biology will be discussed with a review of current status of compatible methods and models for the in silico design and quantitative evaluation of a cell factory.

  11. Preparation of Biocolorant and Eco-Dyeing Derived from Polyphenols Based on Laccase-Catalyzed Oxidative Polymerization

    Directory of Open Access Journals (Sweden)

    Fubang Wang

    2018-02-01

    Full Text Available Natural products have been believed to be a promising source to obtain ecological dyes and pigments. Plant polyphenol is a kind of significant natural compound, and tea provides a rich source of polyphenols. In this study, biocolorant derived from phenolic compounds was generated based on laccase-catalyzed oxidative polymerization, and eco-dyeing of silk and wool fabrics with pigments derived from tea was investigated under the influence of pH variation. This work demonstrated that the dyeing property was better under acidic conditions compared to alkalinity, and fixation rate was the best when pH value was 3. Furthermore, breaking strength of dyed fabrics sharply reduced under the condition of pH 11. Eventually, the dyeing method was an eco-friendly process, which was based on bioconversion, and no mordant was added during the process of dyeing.

  12. A new correction method for determination on carbohydrates in lignocellulosic biomass.

    Science.gov (United States)

    Li, Hong-Qiang; Xu, Jian

    2013-06-01

    The accurate determination on the key components in lignocellulosic biomass is the premise of pretreatment and bioconversion. Currently, the widely used 72% H2SO4 two-step hydrolysis quantitative saccharification (QS) procedure uses loss coefficient of monosaccharide standards to correct monosaccharide loss in the secondary hydrolysis (SH) of QS and may result in excessive correction. By studying the quantitative relationships of glucose and xylose losses during special hydrolysis conditions and the HMF and furfural productions, a simple correction on the monosaccharide loss from both PH and SH was established by using HMF and furfural as the calibrators. This method was used to the component determination on corn stover, Miscanthus and cotton stalk (raw materials and pretreated) and compared to the NREL method. It has been proved that this method can avoid excessive correction on the samples with high-carbohydrate contents. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Genomic sequence of the xylose fermenting, insect-inhabitingyeast, Pichia stipitis

    Energy Technology Data Exchange (ETDEWEB)

    Jeffries, Thomas W.; Grigoriev, Igor; Grimwood, Jane; Laplaza,Jose M.; Aerts, Andrea; Salamov, Asaf; Schmutz, Jeremy; Lindquist, Erika; Dehal, Paramvir; Shapiro, Harris; Jin, Yong-Su; Passoth, Volkmar; Richardson, Paul M.

    2007-06-25

    Xylose is a major constituent of angiosperm lignocellulose,so its fermentation is important for bioconversion to fuels andchemicals. Pichia stipitis is the best-studied native xylose fermentingyeast. Genes from P. stipitis have been used to engineer xylosemetabolism in Saccharomycescerevisiae, and the regulation of the P.stipitis genome offers insights into the mechanisms of xylose metabolismin yeasts. We have sequenced, assembled and finished the genome ofP.stipitis. As such, it is one of only a handful of completely finishedeukaryotic organisms undergoing analysis and manual curation. Thesequence has revealed aspects of genome organization, numerous genes forbiocoversion, preliminary insights into regulation of central metabolicpathways, numerous examples of co-localized genes with related functions,and evidence of how P. stipitis manages to achieve redox balance whilegrowing on xylose under microaerobic conditions.

  14. Characterisation of the Broadly-Specific O-Methyl-transferase JerF from the Late Stages of Jerangolid Biosynthesis

    Directory of Open Access Journals (Sweden)

    Steffen Friedrich

    2016-10-01

    Full Text Available We describe the characterisation of the O-methyltransferase JerF from the late stages of jerangolid biosynthesis. JerF is the first known example of an enzyme that catalyses the formation of a non-aromatic, cyclic methylenolether. The enzyme was overexpressed in E. coli and the cell-free extracts were used in bioconversion experiments. Chemical synthesis gave access to a series of substrate surrogates that covered a broad structural space. Enzymatic assays revealed a broad substrate tolerance and high regioselectivity of JerF, which makes it an attractive candidate for an application in chemoenzymatic synthesis with particular usefulness for late stage application on 4-methoxy-5,6-dihydro-2H-pyran-2-one-containing natural products.

  15. Optimization of upstream and development of cellulose hydrolysis process for cellulosic bio-ethanol production

    International Nuclear Information System (INIS)

    Bae, Hyun Jong; Wi, Seung Gon; Kim, Su Bae; Shin, You Jung; Yi, Ju Hui

    2010-10-01

    The purpose of this project is optimization of upstream and development of cellulose hydrolysis process for cellulosic bio-ethanol production. Research scope includes 1) screening of various microorganisms from decayed biomass in order to search for more efficient lignocellulose degrading microorganism, 2) identification and verification of new cell wall degrading cellulase for application cellulose bioconversion process, and 3) identification and characterization of novel genes involved in cellulose degradation. To find good microorganism candidates for lignocellulose degrading, 75 decayed samples from different areas were assayed in triplicate and analyzed. For cloning new cell wall degrading enzymes, we selected microorganisms because it have very good lignocellulose degradation ability. From that microorganisms, we have apparently cloned a new cellulase genes (10 genes). We are applying the new cloned cellulase genes to characterize in lignocellulsoe degradation that are most important to cellulosic biofuels production

  16. Low-temperature conversion of high-moisture biomass: Topical report, January 1984--January 1988

    Energy Technology Data Exchange (ETDEWEB)

    Sealock, L.J. Jr.; Elliott, D.C.; Butner, R.S.; Neuenschwander, G.G.

    1988-10-01

    Pacific Northwest Laboratory (PNL) is developing a low-temperature, catalytic process that converts high-moisture biomass feedstocks and other wet organic substances to useful gaseous and liquid fuels. The advantage of this process is that it works without the need for drying or dewatering the feedstock. Conventional thermal gasification processes, which require temperatures above 750/degree/C and air or oxygen for combustion to supply reaction heat, generally cannot utilize feedstocks with moisture contents above 50 wt %, as the conversion efficiency is greatly reduced as a result of the drying step. For this reason, anaerobic digestion or other bioconversion processes traditionally have been used for gasification of high-moisture feedstocks. However, these processes suffer from slow reaction rates and incomplete carbon conversion. 50 refs., 21 figs., 22 tabs.

  17. Fossil Energy Program annual progress report for April 1996 through March 1997

    Energy Technology Data Exchange (ETDEWEB)

    Judkins, R.R.

    1997-07-01

    The Oak Ridge National Laboratory (ORNL) Fossil Energy Program research and development activities, performed for the Department of Energy (DOE) Assistant Secretary for Fossil Energy, cover the areas of coal, clean coal technology, gas, petroleum, and support to the Strategic Petroleum Reserve. The coal activities include materials research and development; environmental analysis support; bioprocessing of coal to produce liquid or gaseous fuels; and coal combustion research. The work in support of gas technologies includes activities on the Advanced Turbine Systems Program, primarily in the materials and manufacturing aspects. Several activities are contributing to petroleum technologies in the areas of computational tools for seismic analysis and the use of bioconversion for the removal of impurities from heavy oils. This report contains 32 papers describing the various research activities, arranged under the following topical sections: materials research and development; environmental analysis support; bioprocessing research; coal combustion research; fossil fuel supply modeling and research; and advanced turbine systems.

  18. Membrane engineering in biotechnology: quo vamus?

    Science.gov (United States)

    Rios, Gilbert M; Belleville, Marie-Pierre; Paolucci-Jeanjean, Delphine

    2007-06-01

    Membranes are essential to a range of applications, including the production of potable water, energy generation, tissue repair, pharmaceutical production, food packaging, and the separations needed for the manufacture of chemicals, electronics and a range of other products. Therefore, they are considered to be "dominant technologies" by governments and industry in several prominent countries--for example, USA, Japan and China. When combined with catalysts, membranes are at the basis of life, and membrane-based biomimetism is a key tool to obtain better quality products and environmentally friendly developments for our societies. Biology has a main part in this global landscape because it simultaneously provides the "model" (with natural biological membranes) and represents a considerable field of applications for new artificial membranes (biotreatments, bioconversions and artificial organs). In this article, our objective is to open up this enthralling area and to give our views about the future of membranes in biotechnology.

  19. The biomass like renewable energy in the future

    International Nuclear Information System (INIS)

    Perez Peces, J.

    1993-01-01

    The energetic contribution of biomass in EC and world figures represents a 14% of the whole demand. For developing countries this figure goes up to 35% and can be a source of employment for manpower decreasing in other sectors. At European level the CEC are promoting research areas through JOULE and LEBEN programs. Current European policy with big subsidies for intensive agricultural production has penalized forest and biomass production. Reforestation and biomass energetics crops are going to be a new strategy with 20 million Ha of agricultural soil transformed and between 10 and 20 million ha of marginal soil transformed. Biomass will be promoted keeping in mind environmental benefits like compost production for soil conditioning. A review of the different biomass sources and treatment techniques (bioconversion, thermal conversion and biodigestion), as well as environmental aspects are given

  20. Comparison of ultrasonic and CO₂laser pretreatment methods on enzyme digestibility of corn stover.

    Science.gov (United States)

    Tian, Shuang-Qi; Wang, Zhen-Yu; Fan, Zi-Luan; Zuo, Li-Li

    2012-01-01

    To decrease the cost of bioethanol production, biomass recalcitrance needs to be overcome so that the conversion of biomass to bioethanol becomes more efficient. CO(2) laser irradiation can disrupt the lignocellulosic physical structure and reduce the average size of fiber. Analyses with Fourier transform infrared spectroscopy, specific surface area, and the microstructure of corn stover were used to elucidate the enhancement mechanism of the pretreatment process by CO(2) laser irradiation. The present work demonstrated that the CO(2) laser had potential to enhance the bioconversion efficiency of lignocellulosic waste to renewable bioethanol. The saccharification rate of the CO(2) laser pretreatment was significantly higher than ultrasonic pretreatment, and reached 27.75% which was 1.34-fold of that of ultrasonic pretreatment. The results showed the impact of CO(2) laser pretreatment on corn stover to be more effective than ultrasonic pretreatment.