Biotechnology and Bioengineering (BIOTECHNOL BIOENG)

Publications in this journal

• Article: ONLINE FERMENTATION MONITORING USING FLOW-INJECTION ANALYSIS

  F Valero, J Lafuente, M Poch, C Sola, A N Araujo, Jlfc Lima
  Biotechnology and Bioengineering 05/2013; 36:647-651.
• Article: Beristain–Cardoso, R, Sierra Alvarez R., Roulette P., Razo Flores E., Gomez J. and Field J. A. (2006). Sulfide oxidation under chemolithotrophic denitrifying conditions. Biotechnol Bioeng, 95, 1142-1157.

  Beristain–Cardoso, Sierra Alvarez R, Roulette P, Razo Flores E, Gomez J Filed J
  Biotechnology and Bioengineering 02/2013; 45:1142-1157.
• Article: Knockout of pgdS and ggt genes improves γ-PGA yield in B. subtilis

  Scoffone V, Dondi D, Biino G, Borghese G, Pasini D, Galizzi A, Calvio C
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  ABSTRACT: One of the emerging biopolymers that are currently under active investigation is bacterial poly(γ-glutamic acid) (γ-PGA). However, before its full industrial exploitation, a substantial increase in microbial productivity is required. γ-PGA obtained from the Bacillus subtilis laboratory strain 168 offers the advantage of a producer characterized by a well defined genetic framework and simple manipulation techniques. In this strain, the knockout of genes for the major γ-PGA degrading enzymes, pgdS and ggt, leads to a considerable improvement in polymer yield, which attains levels analogous to the top wild γ-PGA producer strains. This study highlights the convenience of using the laboratory strain of B. subtilis over wild isolates in designing strain improvement strategies aimed at increasing γ-PGA productivity
  Biotechnology and Bioengineering 01/2013;
• Article: Micropatterned polyelectrolyte nanofilms promote alignment and myogenic differentiation of C2C12 cells in standard growth media

  Ilaria E. Palamà, Stefania D'Amone, Addolorata M. L. Coluccia, Giuseppe Gigli
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  ABSTRACT: Alignment of skeletal myoblasts is considered a critical step during myotube formation. The C2C12 cell line is frequently used as a model of skeletal muscle differentiation that can be induced by lowering the serum concentration in standard culture flasks. In order to mimic the striated architectures of skeletal muscles in vitro, micro-patterning techniques and surface engineering have been proven as useful approaches for promoting elongation and alignment of C2C12 myoblasts, thereby enhancing the outgrowth of multi-nucleated myotubes upon switching from growth media (GM) to differentiative media (DM). Herein, a layer-by-layer polyelectrolyte multilayer deposition was combined with a micro-molding in capillaries (MIMIC) method to simultaneously provide biochemical and geometrical instructive cues that induced the formation of tightly apposed and parallel arrays of differentiating myotubes from C2C12 cells maintained in GM media for 15 days. This study focuses on two different types of patterned/self-assembled nanofilms based on alternated layers of poly (allylamine hydrochloride) (PAH)/poly(sodium 4-styrene-sulfonate) (PSS) as biocompatible but not biodegradable polymeric structures, or poly-L-arginine sulfate salt (pARG)/dextran sulfate sodium salt (DXS) as both biocompatible and biodegradable surfaces. The influence of these microstructures as well as of the nanofilm composition on C2C12 skeletal muscle cells' differentiation and viability was evaluated and quantified, pointing to give a reference for skeletal muscle regenerative potential in culture conditions that do not promote it. At this regard, our results validate PEM microstructured devices, to a greater extent for (PAH/PSS)5-coated microgrooves, as biocompatible and innovative tools for tissue engineering applications and molecular dissection of events controlling C2C12 skeletal muscle regeneration without switching to their optimal differentiative culture media in vitro
  Biotechnology and Bioengineering 07/2012;
• Article: Data fusion based assessment of raw materials in mammalian cell culture

  Hae Woo Lee, Andrew Christie, Jin Xu, Seongkyu Yoon
  Biotechnology and Bioengineering 05/2012;
• Article: The roles of RGD and grooved topography in the adhesion, morphology and differentiation of C2C12 Skeletal Myoblasts

  Wang P-Y, Thissen H, Tsai W-B
  Biotechnology and Bioengineering 01/2012;
• Article: Microflotation performance for algal separation

  James Hanotu, H.C. Hemaka Bandulasena, William B. Zimmerman
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  ABSTRACT: The performance of microflotation, dispersed air flotation with microbubble clouds with bubble size about 50 µm, for algae separation using fluidic oscillation for microbubble generation is investigated. This fluidic oscillator converts continuous air supply into oscillatory flow with a regular frequency to generate bubbles of the scale of the exit pore. Bubble characterization results showed that average bubble size generated under oscillatory air flow state was 86 µm, approximately twice the size of the diffuser pore size of 38 µm. In contrast, continuous air flow at the same rate through the same diffusers yielded an average bubble size of 1,059 µm, 28 times larger than the pore size. Following microbubble generation, the separation of algal cells under fluidic oscillator generated microbubbles was investigated by varying metallic coagulant types, concentration and pH. Best performances were recorded at the highest coagulant dose (150 mg/L) applied under acidic conditions (pH 5). Amongst the three metallic coagulants studied, ferric chloride yielded the overall best result of 99.2% under the optimum conditions followed closely by ferric sulfate (98.1%) and aluminum sulfate with 95.2%. This compares well with conventional dissolved air flotation (DAF) benchmarks, but has a highly turbulent flow, whereas microflotation is laminar with several orders of magnitude lower energy density.
  Biotechnology and Bioengineering 01/2012;
• Article: Critical review of activated sludge modelling: State of process knowledge, modelling concepts and limitations

  H. Hauduc, L. Rieger, A. Oehmen, M.C.M. van Loosdrecht, Y. Comeau, A. Héduit, P.A. Vanrolleghem, S. Gillot
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  ABSTRACT: This work critically reviews modelling concepts for standard activated sludge wastewater treatment processes (e.g. hydrolysis, growth and decay of organisms, etc.) for some of the most commonly used models. Based on a short overview on the theoretical biochemistry knowledge this review should help model users to better understand i) the model concepts used; ii) the differences between models and iii) the limits of the models. The seven analysed models are: (1) ASM1; (2) ASM2d; (3) ASM3; (4) ASM3+BioP; (5) ASM2d+TUD; (6) Barker&Dold model; (7) UCTPHO+. Nine standard processes are distinguished and discussed in the present work: hydrolysis; fermentation; ordinary heterotrophic organisms (OHO) growth; autotrophic nitrifying organisms (ANO) growth; OHO & ANO decay; poly-hydroxyalkanoates (PHA) storage; polyphosphate (polyP) storage; phosphorus accumulating organisms PAO) growth and PAO decay. For a structured comparison, a new schematic representation of these processes is proposed. Each process is represented as a reaction with consumed components on the left of the figure and produced components on the right. Standardised icons, based on shapes and colour codes, enable the representation of the stoichiometric modelling concepts and kinetics. This representation allows highlighting the conceptual differences of the models, and the level of simplification between the concepts and the theoretical knowledge. The model selection depending on their theoretical limitations and the main research needs to increase the model quality are finally discussed
  Biotechnology and Bioengineering 01/2012;
• Article: Mycoremediation of di(2-ethylhexyl)phthalate, the alarming plasticizer in PVC blood storage bag

  Faseela, Pradeep, Sarath Josh, M. K, Balachandran, Sudha Devi, Sailas Benjamin
  Biotechnology and Bioengineering 01/2011;
• Article: A general kinetic model for biological nutrient removal activated sludge systems: model development.

  Zhi-rong Hu, M C Wentzel, G A Ekama
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  ABSTRACT: In this article, a kinetic model is developed and presented for biological nutrient removal (BNR) activated sludge (BNRAS) systems in general, but for external nitrification (EN) BNRAS (ENBNRAS) systems in particular. The model is based on the UCTPHO model, but includes some significant modifications, such as anoxic P uptake and associated denitrification by phosphorus accumulating organisms (PAOs). Some key features of the model are described and discussed before the model is presented. Model evaluation will be addressed in another article (Hu et al., 2007).
  Biotechnology and Bioengineering 01/2008; 98(6):1242-58.
• Article: In vitro study of using calcium phosphate cement as immunoisolative device to enclose insulinoma/agarose microspheres as bioartificial pancreas.

  Yang Kai-Chiang, Yang Ching-Yao, Wu Chang-Chin, Kuo Tzong-Fu, Lin Feng-Huei
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  ABSTRACT: In this study, the feasibility of using calcium phosphate cement (CPC) as immunoisolative device to enclose insulinoma/agarose microspheres as bioartificial pancreas was evaluated. We fabricated a chamber by CPC and utilized X-ray diffraction, Scanning electron microscope and Mercury intrusion porosimetry to identify the characters of the CPC chamber. The nominal molecular weight cut-off and cytotoxicity of CPC chamber were also evaluated. An insulinoma cell line (RIN-m5F) was chosen as insulin source and encapsulated in agarose microspheres and then enclosed in preformed CPC chamber. Insulin secretion was analyzed by Enzyme-linked immunosorbant assay to evaluate the function of insulinoma enclosed in CPC chamber. Results showed that the CPC chamber was non-cytotoxicity to insulinoma and can block the penetration of molecules which molecular weight larger than 12.4 kDa. Insulinoma inside the CPC chamber can secrete insulin in stable level for 30 days. This study indicated that we may use CPC as immunoisolative material to enclose insulinoma/agarose microspheres as bioartificial pancreas.
  Biotechnology and Bioengineering 01/2008; 98(6):1288-95.
• Article: Defined protein and animal component-free NS0 fed-batch culture.

  Erika Spens, Lena Häggström
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  ABSTRACT: A chemically defined protein and animal component-free fed-batch process for an NS0 cell line producing a human IgG(1) antibody has been developed. The fed-batch feed profile was optimised in a step-wise manner. Depletion of measurable compounds was determined by direct analysis. The cellular need for non-measurable compounds was tested by continued culturing of cell suspension, removed from the bioreactor, in shake-flasks supplemented with critical substances. In the final fed-batch culture, 8.4 x 10(6) viable cells mL(-1) and 625 mg antibody L(-1) was obtained as compared to 2.3 x 10(6) cells mL(-1) and 70 mg antibody L(-1) in batch. The increase in cell density, in combination with a prolonged declining phase where antibody formation continued, resulted in a 6.2-fold increase in total cell yield, a 10.5-fold increase in viable cell hours and an 11.4-fold increase in product yield. These improvements were obtained by using a feed with glucose, glutamine, amino acids, lipids, sodium selenite, ethanolamine and vitamins. Specifically, supplementation with lipids (cholesterol) had a drastic effect on the maximum viable cell density. Calcium, magnesium and potassium were not depleted and a feed also containing iron, lithium, manganese, phosphorous and zinc did not significantly enhance the cell yield. The growth and death profiles in the final fed-batch indicated that nutrient deprivation was not the main cause of cell death. The ammonium concentration and the osmolality increased to potentially inhibitory levels, but an imbalance in the supply of growth/survival factors may also contribute to termination of the culture.
  Biotechnology and Bioengineering 01/2008; 98(6):1183-94.
• Article: Non-native protein aggregation kinetics.

  Christopher J Roberts
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  ABSTRACT: Experimental kinetics of non-native protein aggregation are of practical importance in that they help dictate viable processing, formulation, and storage conditions for biotechnology products, and appear to play a role in determining the onset of a number of diseases. Fundamentally, aggregation kinetics provide insights into the identity of key intermediates in the process, and quantitative tests of available models of aggregation. Although aggregation kinetics often display seemingly disparate behaviors across different proteins and sample conditions, this review illustrates how many of these can be understood within a general framework that treats aggregation as a multi-stage process, and how most available kinetic models of aggregation can be grouped hierarchically in terms of which stage(s) they include. This provides an aid for workers seeking a mechanistic interpretation of in vitro aggregation kinetics, for discriminating among competing models, and in designing experiments to assess in vitro protein stability. Limitations and the utility of purely kinetic approaches to studying aggregation, clarifications of common misperceptions regarding experimental aggregation kinetics, and some outstanding challenges in the field are briefly discussed.
  Biotechnology and Bioengineering 01/2008; 98(5):927-38.
• Article: Inorganic nanoparticles for transfection of mammalian cells and removal of viruses from aqueous solutions.

  Nils Link, Tobias J Brunner, Imke A J Dreesen, Wendelin J Stark, Martin Fussenegger
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  ABSTRACT: Owing to their small size, synthetic nanoparticles show unprecedented biophysical and biochemical properties which may foster novel advances in life-science research. Using flame-spray synthesis technology we have produced non-coated aluminum-, calcium-, cerium-, and zirconium-derived inorganic metal oxide nanoparticles which not only exhibit high affinity for nucleic acids, but can sequester such compounds from aqueous solution. This non-covalent DNA-binding capacity was successfully used to transiently transfect a variety of mammalian cells including human, reaching transfection efficiencies which compared favorably with classic calcium phosphate precipitation (CaP) procedures and lipofection. In this straightforward protocol, transfection was enabled by simply mixing nanoparticles with DNA in solution prior to addition to the target cell population. Transiently transfected cells showed higher production levels of the human secreted glycoprotein SEAP compared to isogenic populations transfected with established technologies. Inorganic metal oxide nanoparticles also showed a high binding capacity to human-pathogenic viruses including adenovirus, adeno-associated virus and human immunodeficiency virus type 1 and were able to clear these pathogens from aqueous solutions. The DNA transfection and viral clearance capacities of inorganic metal oxide nanoparticles may provide cost-effective biopharmaceutical manufacturing and water treatment in developing countries.
  Biotechnology and Bioengineering 01/2008; 98(5):1083-93.
• Article: Pseudo reaction kinetics of organic degradation products in dilute-acid-catalyzed corn stover pretreatment hydrolysates.

  Shou-Feng Chen, Richard A Mowery, C Kevin Chambliss, G Peter van Walsum
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  ABSTRACT: A variety of degradation products are produced upon pretreatment of lignocellulosic biomass with dilute acid. To date, the complexity of these samples has significantly limited the scope of efforts to perform summative analyses of degradation products. Qualitative and quantitative interrogation of hydrolysates is also paramount to identifying potential correlations between pretreatment chemistry and microbial inhibition in downstream bioconversion processes. A recently developed reversed-phase high performance liquid chromatography technique with UV detection has been applied to perform quantitative assessments of a variety of hydrolysate components as a function of pretreatment time and temperature. Correlations of product concentrations to the pretreatment severity function indicate differing responses of various compounds to the kinetic influences of temperature and reaction time. Of the compounds measured, four demonstrated initial accumulation rates were sufficiently linear over the time period tested to enable determination of activation energy E(a). All four compounds appear to demonstrate higher E(a) than that assumed in the commonly applied severity function. Overall accumulation trends for most compounds indicated similar under-estimation of apparent activation energy by the severity function. Biotechnol. Bioeng. 2007;98: 1135-1145. (c) 2007 Wiley Periodicals, Inc.
  Biotechnology and Bioengineering 01/2008; 98(6):1135-45.