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William R Keller, Steven T Evans, Gisela Ferreira, David Robbins, Steven M Cramer
In this paper, a simulation tool was employed to identify and appropriately incorporate differences between MiniColumns and benchtop column systems. It was first demonstrated that including multi-step gradients and fraction collection into the simulations resulted in improved agreement between simulated and experimental linear gradient profiles as well as calculated first moments in the MiniColumn experiments. Step elution experiments of binary mixtures (a monoclonal antibody and one of three model proteins) were then carried out to examine comparability of the MiniColumns to the benchtop system...
August 1, 2017: Journal of Chromatography. A
T P F Cabral, N C Bellini, K R Assis, C C C Teixeira, A D Lanchote, H Cabral, L A P de Freitas
The aim of this work was to obtain microencapsulated stable Aspergillus niger peptidases by post fermentation spray drying. The enzymatic extract was evaluated before and after spray drying microencapsulation to verify the effects of five different process parameters on the extract enzymatic activity, i.e. air flow, extract feed rate, drying temperature, homogenizing time and weight ratio of extract to encapsulation material. The optimal conditions were determined by desirability functions and experimentally confirmed...
August 14, 2017: Journal of Microencapsulation
Frank Delvigne, Ralf Takors, Rob Mudde, Walter van Gulik, Henk Noorman
Efficient optimization of microbial processes is a critical issue for achieving a number of sustainable development goals, considering the impact of microbial biotechnology in agrofood, environment, biopharmaceutical and chemical industries. Many of these applications require scale-up after proof of concept. However, the behaviour of microbial systems remains unpredictable (at least partially) when shifting from laboratory-scale to industrial conditions. The need for robust microbial systems is thus highly needed in this context, as well as a better understanding of the interactions between fluid mechanics and cell physiology...
August 14, 2017: Microbial Biotechnology
Chao Li, Xin Chen, Fuyuan Zhang, Xingxing He, Guozhen Fang, Jifeng Liu, Shuo Wang
Glucose assay is of great scientific significance in clinical diagnostics and bioprocess monitoring and to design new glucose receptor is necessary for development of more sensitive, selective and robust glucose detection techniques. Herein, a series of cyclic peptides (CPs) glucose receptor were designed to mimic the binding sites of glucose binding protein (GBP) and CPs' sequence contained amino acid sites Asp, Asn, His, Asp, Arg, which constituted the first layer interactions of GBP. The properties of these CPs used as a glucose receptor or substitute for the GBP were studied by using quartz crystal microbalance (QCM) technique...
August 14, 2017: Analytical Chemistry
Chiara Gandini, Loredana Tarraran, Denis Kalemasi, Enrica Pessione, Roberto Mazzoli
Lactic acid bacteria (LAB) are among the most interesting organisms for industrial processes with a long history of application as food starters and biocontrol agents, and an underexploited potential for biorefineries converting biomass into high-value compounds. Lactic acid (LA), their main fermentation product, is among the most requested chemicals owing to its broad range of applications. Notably, LA polymers, i.e., polylactides, have high potential as biodegradable substitutes of fossil-derived plastics...
August 12, 2017: Biotechnology and Bioengineering
Ryohei Ogawa, Go Kagiya, Akihiko Watanabe, Akihiro Morii, Zheng-Guo Cui, Takashi Kondo
It has been pointed out that ultrasound could be used as a controller for bioprocesses including gene expression since its energy can noninvasively reach deep in the body. Gene expression may be timely and spatially controlled by ultrasound, thus providing necessary bioactive proteins for the targeted tissue in a timely fashion. Although there are many processes involved in gene expression control, one of the most important processes is transcription, and the promoter plays an essential role in it. There are several promoters known to be activated in response to ultrasound irradiation ...
2017: Methods in Molecular Biology
Jin Qian, Li Wei, Yaoguo Wu, Qilin Wang, Xiaoying Fu, Xiaochao Zhang, Xing Chang, Lianlian Wang, Xiangjun Pei
A comparative study on denitrifying sludge granulation with different electron donors (sulfide, thiosulfate and organics) was carried out. Longer time was spent on sulfide-denitrifying granular sludge (DGS) cultivation (88 days) than thiosulfate- and organics-DGS cultivations (57 days). All the three DGS were characterized in terms of particle size distribution, sludge settling ability (indicated by sludge volume index and settling velocity), permeability (indicated by fractal dimension) and extracellular polymeric substances (EPS, including polysaccharide and protein) secretion...
July 19, 2017: Chemosphere
Juan Lopez-Trujillo, Miguel A Medina-Morales, Ariel Sanchez-Flores, Carlos Arevalo, Juan A Ascacio-Valdes, Miguel Mellado, Cristobal N Aguilar, Antonio F Aguilera-Carbo
Commercial cellulase production has increased in recent years and consistent research has been carried out to improve levels of β-glucosidase. Bioprocesses have been successfully adapted to produce this enzyme, with solid-state fermentations as the best-suited technique involving fungi. The aim of this study was to use leaves of tarbush (Flourensia cernua), an abundant shrub of the Chihuahuan Desert, as a carbon source for β-glucosidase production by Aspergillus niger. During the solid bioprocess, this enzyme reached its peak production at 36 h of culture with 3876...
August 2017: 3 Biotech
Keju Jing, Yuanwei Tang, Chuanyi Yao, Ehecatl Antonio Del Rio-Chanona, Xueping Ling, Dongda Zhang
L-tryptophan is an essential amino acid widely used in food and pharmaceutical industries. However, its production via Escherichia coli fermentation suffers severely from both low glucose conversion efficiency and acetic acid inhibition, and to date effective process control methods have rarely been explored to facilitate its industrial scale production. To resolve these challenges, in the current research an engineered strain of Escherichia coli was used to overproduce L-tryptophan. To achieve this, a novel dynamic control strategy which incorporates an optimised anthranilic acid feeding into a dissolved oxygen-stat (DO-stat) glucose feeding framework was proposed for the first time...
August 7, 2017: Biotechnology and Bioengineering
D Marquard, C Schneider-Barthold, S Düsterloh, T Scheper, P Lindner
In situ Microscopy (ISM) is an optical non-invasive technique to monitor cells in bioprocesses in real-time. Escherichia coli is the most studied and used organism in biotechnology. In this article the cell density in Escherichia coli cultivations was monitored by applying ISM in these cultivations. The acquired images were analyzed with an image processing algorithm to determine the turbidity of the cultivation medium. In three cultivations the cell density was monitored with the algorithm and offline samples were taken to determine the dry cell mass (DCM)...
August 2, 2017: Journal of Biotechnology
Raphael Hermano Santos Diniz, Juan C Villada, Mariana Caroline Tocantins Alvim, Pedro Marcus Pereira Vidigal, Nívea Moreira Vieira, Mónica Lamas-Maceiras, María Esperanza Cerdán, María-Isabel González-Siso, Petri-Jaan Lahtvee, Wendel Batista da Silveira
The thermotolerant yeast Kluyveromyces marxianus displays a potential to be used for ethanol production from both whey and lignocellulosic biomass at elevated temperatures, which is highly alluring to reduce the cost of the bioprocess. Nevertheless, contrary to Saccharomyces cerevisiae, K. marxianus cannot tolerate high ethanol concentrations. We report the transcriptional profile alterations in K. marxianus under ethanol stress in order to gain insights about mechanisms involved with ethanol response. Time-dependent changes have been characterized under the exposure of 6% ethanol and compared with the unstressed cells prior to the ethanol addition...
August 3, 2017: Applied Microbiology and Biotechnology
Marco Jenzsch, Christian Bell, Stefan Buziol, Felix Kepert, Harald Wegele, Christian Hakemeyer
Process analytical technology (PAT), the regulatory initiative for incorporating quality in pharmaceutical manufacturing, is an area of intense research and interest. If PAT is effectively applied to bioprocesses, this can increase process understanding and control, and mitigate the risk from substandard drug products to both manufacturer and patient. To optimize the benefits of PAT, the entire PAT framework must be considered and each elements of PAT must be carefully selected, including sensor and analytical technology, data analysis techniques, control strategies and algorithms, and process optimization routines...
August 4, 2017: Advances in Biochemical Engineering/biotechnology
Mladen Pavlečić, Tonči Rezić, Mirela Ivančić Šantek, Predrag Horvat, Božidar Šantek
Fossil fuels are still major energy sources, but the search for renewable energy sources has been encouraged. Bioethanol has been recognized as an alternative to fossil fuels and nowadays it represents more than 90% of the global biofuel production. Bioethanol production from raw sugar beet cossettes as a semi-solid substrate was studied. The study was carried out in the horizontal rotating tubular bioreactor (HRTB) with Saccharomyces cerevisiae as a microbial production strain. The impact of different combinations of HRTB operational parameters such as, rotation speed (5-15 min(-1)), rotation type [constant or interval (3-15 min h(-1))] and working volume (ratio V W/V T = 0...
August 2, 2017: Bioprocess and Biosystems Engineering
Shinobu Oda
Bioconversions such as enzymatic and microbial transformations are attractive alternatives to organic synthesis because of practical advantages such as resource conservation, energy efficiency, and environmentally harmonic properties. In addition, the production of secondary metabolites through microbial fermentation is also useful for manufacturing pharmaceuticals, agricultural chemicals, and aroma compounds. For microbial production of useful chemicals, the authors have developed three unique interfacial bioprocesses: a solid-liquid interface bioreactor (S/L-IBR), a liquid-liquid interface bioreactor (L/L-IBR), and an extractive liquid-surface immobilization (Ext-LSI) system...
2017: Journal of Oleo Science
Gilson Campani, Gabriel Gonçalves da Silva, Teresa Cristina Zangirolami, Marcelo Perencin de Arruda Ribeiro
Temperature influences the rates of oxygen transfer (OTR) and uptake (q O2) in aerobic bioprocesses. Hence, joint analysis of q O2 and OTR at variable temperature is essential for bioprocess optimization and control. However, no such analyses have yet been reported for cultures of engineered E. coli producing recombinant proteins. E. coli cultivations at different temperatures (27-37 °C) were performed using a 5-L stirred tank bioreactor (STB), and a 5-L airlift bioreactor (ALB) was used to measure k L a and validate models of q O2 and OTR...
July 27, 2017: Bioprocess and Biosystems Engineering
M Lourdes Velez-Suberbie, John Pj Betts, Kelly L Walker, Colin Robinson, Barney Zoro, Eli Keshavarz-Moore
High throughput automated fermentation systems have become a useful tool in early bioprocess development. In this study, we investigated a 24 x 15 mL single use microbioreactor system, ambr 15f, designed for microbial culture. We compared the fed-batch growth and production capabilities of this system for two Escherichia coli strains, BL21 (DE3) and MC4100, and two industrially relevant molecules, hGH and scFv. In addition, different carbon sources were tested using bolus, linear or exponential feeding strategies, showing the capacity of the ambr 15f system to handle automated feeding...
July 27, 2017: Biotechnology Progress
Antonin Prévoteau, Korneel Rabaey
Microbial electrochemistry has from the onset been recognized for its sensing potential due to the microbial ability to enhance signals through metabolic cascades, its relative selectivity toward substrates, and the higher stability conferred by the microbial ability to self-replicate. The greatest challenge has been to achieve stable and efficient transduction between a microorganism and an electrode surface. Over the past decades, a new kind of microbial architecture has been observed to spontaneously develop on polarized electrodes: the electroactive biofilm (EAB)...
July 26, 2017: ACS Sensors
David Havlik, Ulrike Brandt, Kathrin Bohle, André Fleißner
BACKGROUND: Filamentous fungi are commonly used as production hosts for bulk enzymes in biotechnological applications. Their robust and quick growth combined with their ability to secrete large amounts of protein directly into the culture medium makes fungi appealing organisms for the generation of novel production systems. The red bread mold Neurospora crassa has long been established as a model system in basic research. It can be very easily genetically manipulated and a wealth of molecular tools and mutants are available...
July 25, 2017: Microbial Cell Factories
Norma A Valdez-Cruz, Greta I Reynoso-Cereceda, Saumel Pérez-Rodriguez, Sara Restrepo-Pineda, Jesus González-Santana, Alejandro Olvera, Guadalupe Zavala, Alejandro Alagón, Mauricio A Trujillo-Roldán
BACKGROUND: Shake flasks are widely used during the development of bioprocesses for recombinant proteins. Cultures of recombinant Escherichia coli with orbital mixing (OM) have an oxygen limitation negatively affecting biomass growth and recombinant-protein production. With the aim to improve mixing and aeration in shake flask cultures, we analyzed cultures subjected to OM and the novel resonant acoustic mixing (RAM) by applying acoustic energy to E. coli BL21-Gold (DE3): a producer of recombinant phospholipase A2 (rPLA2) from Micrurus laticollaris snake venom...
July 25, 2017: Microbial Cell Factories
Noemí Dorival-García, Jonathan Bones
Despite their advantages, there is concern that single-use systems used in biopharmaceutical manufacture might release potentially toxic substances during standard unit operations that negatively impact cell growth. Characterization of the extractables profile for single-use systems is necessary to know which compounds potentially become leachables under operational cell culture conditions. A key issue in the design of extractables studies is the composition of the model solvent, in particular its pH and polarity...
June 29, 2017: Journal of Chromatography. A
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