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Biotechnology Progress

Amish Asthana, Charles McRae White, Megan Douglass, William S Kisaalita
The lack of prediction accuracy during drug development and screening risks complications during human trials, such as drug-induced liver injury (DILI), and has led to a demand for robust, human cell-based, in vitro assays for drug discovery. Microporous polymer-based scaffolds offer an alternative to the gold standard flat tissue culture plastic (2D TCPS) and other 3D cell culture platforms as the porous material entraps cells, making it advantageous for automated liquid handlers and high-throughput screening (HTS)...
February 21, 2018: Biotechnology Progress
Seo-Young Park, Thomas M Reimonn, Cyrus Agarabi, Kurt Brorson, Seongkyu Yoon
Amino acids and glucose consumption, cell growth and monoclonal antibody (mAb) production in mammalian cell culture are key considerations during upstream process and particularly media optimization. Understanding the interrelations and the relevant cellular physiology will provide insight for setting strategy of robust and effective mAb production. The aim of this study was to further our understanding of nutrient consumption metabolism, since this could have significant impact on enhancing mAb titer, cell proliferation, designing feeding strategies, and development of feed media...
February 21, 2018: Biotechnology Progress
Ahasanul Karim, Abu Yousuf, M Amirul Islam, Yasir H Naif, Che Ku Mohammad Faizal, Md Zahangir Alam, Domenico Pirozzi
The aim of the study was to investigate the feasibility of using irreversible electroporation (EP) as a microbial cell disruption technique to extract intracellular lipid within short time and in an eco-friendly manner. An EP circuit was designed and fabricated to obtain 4 kV with frequency of 100 Hz of square waves. The yeast cells of Lipomyces starkeyi (L. starkeyi) were treated by EP for 2-10 min where the distance between electrodes was maintained at 2, 4 and 6 cm. Colony forming units (CFU) were counted to observe the cell viability under the high voltage electric field...
February 21, 2018: Biotechnology Progress
Andrew D Tustian, Linus Laurin, Henrik Ihre, Travis Tran, Robert Stairs, Hanne Bak
There is strong interest in the production of bispecific monoclonal antibodies that can simultaneously bind two distinct targets or epitopes to achieve novel mechanisms of action and efficacy. Regeneron's bispecific technology, based upon a standard IgG, consists of a heterodimer of two different heavy chains, and a common light chain. Co-expression of two heavy chains leads to the formation of two parental IgG impurities, the removal of which is facilitated by a dipeptide substitution in the Fc portion of one of the heavy chains that ablates Fc Protein A binding...
February 21, 2018: Biotechnology Progress
B S Priyanka, Navin K Rastogi
The present work deals with the extraction of lipase and amylase from enzyme mixture by employing liquid emulsion membranes (LEM). The electrostatic interaction between enzymes and reverse micellar surfactant polar head group plays an important role for selective extraction of two different enzymes having different isoelectric points. The optimised conditions for lipase extraction (pH 7.0) resulted in the purification fold and activity recovery of 5.43 fold and 89.53%, respectively, whereas, in case of amylase (pH 9...
February 21, 2018: Biotechnology Progress
Yi Feng Lee, Matthias Jöhnck, Christian Frech
The efficiencies of mono gradient elution and dual salt-pH gradient elution for separation of six mAb charge and size variants on a preparative-scale ion exchange chromatographic resin are compared in this study. Results showed that opposite dual salt-pH gradient elution with increasing pH gradient and simultaneously decreasing salt gradient is best suited for the separation of these mAb charge and size variants on Eshmuno® CPX. Besides giving high binding capacity, this type of opposite dual salt-pH gradient also provides better resolved mAb variant peaks and lower conductivity in the elution pools compared to single pH or salt gradients...
February 21, 2018: Biotechnology Progress
Sen Xu, Rubin Jiang, Roland Mueller, Nadja Hoesli, Thomas Kretz, John Bowers, Hao Chen
Lactate metabolism variations are frequently encountered in mammalian cell culture processes, especially during process scale-up. In this study, we took a multipronged approach to investigate the impact of pH, pCO2 , osmolality, base addition, and mixing conditions on the observed lactate variations in a Chinese Hamster Ovary (CHO) fed-batch process at 2,000 L scale. Two cultivating methods, CO2 -controlled and pH-controlled, were used to decouple the individual and synergistic effects from those factors. The individual effects from pH, pCO2 , and osmolality on lactate consumption/reproduction in the stationary phase were insignificant in the ranges studied though the initial lactate production rates varied...
February 21, 2018: Biotechnology Progress
Andrea Svoradová, Lenka Kuželová, Jaromír Vašíček, Lucia Olexíková, Peter Chrenek
The goal of this study was to evaluate effect of slow freezing and vitrification methods on the viability of chicken blastodermal cells (BCs). Proper aliquot of isolated BCs were diluted in the freezing medium composed of 10% DMSO and frozen in the freezing vessel BICELL to reach desired temperature up to -80°C. Then samples were immersed in liquid nitrogen. Other cell aliquot was vitrified in solution containing 10% DMSO and samples were immediately immersed in the liquid nitrogen. The viability of fresh and frozen/thawed BCs was evaluated using Trypan blue method and flow cytometry...
February 1, 2018: Biotechnology Progress
Larissa Maehara, Sandra C Pereira, Adilson J Silva, Cristiane S Farinas
The efficient use of renewable lignocellulosic feedstocks to obtain biofuels and other bioproducts is a key requirement for a sustainable biobased economy. This requires novel and effective strategies to reduce the cost contribution of the cellulolytic enzymatic cocktails needed to convert the carbohydrates into simple sugars, in order to make large-scale commercial processes economically competitive. Here, we propose the use of the whole solid-state fermentation (SSF) medium of mixed filamentous fungi as an integrated one-pot strategy for on-site enzyme production, biomass hydrolysis, and ethanol production...
February 1, 2018: Biotechnology Progress
Shu-Ping Zou, Kai Gu, Yu-Guo Zheng
Halohydrin dehalogenase (HHDH)-mediated dehalogenation of 1,3-dichloro-2-propanol (1,3-DCP) is a key step in the chemoenzymatic synthesis of epichlorohydrin (ECH) from glycerol. In this study, a covalent immobilization strategy was employed to enhance the stability of Agrobacterium tumefaciens HHDH by using epoxy resin ES-103B as a carrier. Under optimal conditions, the activity recovery of ES-103B-immobilized HHDH (HHDH@ES-103B) was 62.4% and the specific activity was 1604 U/g. The HHDH@ES-103B exhibited excellent thermostability, with a half-life of 68...
February 1, 2018: Biotechnology Progress
Livnat Afriat-Jurnou, Rami Cohen, Irina Paluy, Ran Ben-Adiva, Itamar Yadid
Inulinases are fructofuranosyl hydrolases that target the β-2,1 linkage of inulin and hydrolyze it into fructose, glucose and inulooligosaccharides (IOS), the latter are of growing interest as dietary fibers. Inulinases from various microorganisms have been purified, characterized and produced for industrial applications. However, there remains a need for inulinases with increased catalytic activity and better production yields to improve the hydrolysis process and fulfill the growing industrial demands for specific fibers...
February 1, 2018: Biotechnology Progress
Diego Morales, Adriana J Piris, Alejandro Ruiz-Rodriguez, Marin Prodanov, Cristina Soler-Rivas
Three extraction methods were sequentially combined to obtain fractions from Lentinula edodes (shiitake mushrooms) containing bioactive compounds against cardiovascular diseases (CVDs). Fruiting bodies were first extracted with plain water, obtained residue was then submitted to supercritical fluid extraction (SFE) and remaining residue submitted to hot water extraction. Sequential design allowed re-utilization of the non-extracted material as raw material for the successive extractions increasing extraction yields and separating interesting compounds...
February 1, 2018: Biotechnology Progress
Agnes Janoska, María Vázquez, Marcel Janssen, Rene H Wijffels, María Cuaresma, Carlos Vílchez
A novel liquid foam-bed photobioreactor has been shown to hold potential as an innovative technology for microalgae production. In this study a foam stabilizing agent has been selected which fits the requirements of use in a liquid foam-bed photobioreactor. Four criteria were used for an optimal surfactant: the surfactant should have good foaming properties, should not be rapidly biodegradable, should drag up microalgae in the foam formed, and it should not be toxic for microalgae. Ten different surfactants (non-ionic, cationic and anionic) and two microalgae genera (Chlorella and Scenedesmus) were compared on the above-mentioned criteria...
February 1, 2018: Biotechnology Progress
Yuji Haraguchi, Yuki Kagawa, Akiyuki Hasegawa, Hirotsugu Kubo, Tatsuya Shimizu
Confluent cultured cells on a temperature-responsive culture dish can be harvested as an intact cell sheet by decreasing temperature below 32°C. A three-dimensional (3-D) tissue can be fabricated by the layering of cell sheets. A resulting 3-D multi-layered cell sheet-tissue on a temperature-responsive culture dish can be also harvested without any damage by only temperature decreasing. For shortening the fabrication time of the 3-D multi-layered constructs, we attempted to layer cell sheets on a temperature-responsive culture dish with centrifugation...
January 18, 2018: Biotechnology Progress
Thi Thu Tra Tran, Khanh Tien Nguyen, Van Viet Man Le
Recently, ultrasound was demonstrated to increase enzyme activity in food industry. In most studies, an enzyme-substrate mixture was ultrasonicated. Very little is reported on the ultrasonication of enzyme preparation; the effects of ultrasonication variables on the enzyme activity and properties remained unclear. In this study, an α-amylase preparation was ultrasonicated under different conditions. At the ultrasonic frequency, power, temperature and time of 20 kHz, 25 W/mL, 30°C and 75 sec, respectively the secondary structure of the α-amylase was changed and that improved the catalytic activity by 47% over the control...
January 18, 2018: Biotechnology Progress
Hyo Helen Chung, Lynette Buck, Kristi Daris, Brent Welborn, Quanzhou Luo, Jette Wypych
Monoclonal antibodies (mAbs) are composed of two heavy chain (HC) and two light chain (LC) polypeptides. The proper folding and assembly of HC and LC is critical for antibody production. Current dogma indicates that the free HCs are retained in the endoplasmic reticulum (ER) unless assembled with LCs into antibodies, while the LCs on the other hand can be secreted as free monomer or dimer molecules. In this study, high levels of extracellular HC homodimers (7%-45%) were observed in the cell culture media during cell line development for mAb1...
January 17, 2018: Biotechnology Progress
Kseniya A Sheshukova, Lisa R Wilken
Transgenic plant systems have successfully been used to express recombinant proteins, including rice seed-expressed recombinant human serum albumin (rHSA), without the risk of contamination of human pathogens. Developing an efficient extraction process is critical as the step determines recombinant protein concentration and purity, quantity of impurities, and process volume. This paper evaluates the effect of pH and time on the extraction and stability of rHSA. The amount of rHSA in clarified extract after 60 min of solubilization increased with pH from 0...
January 8, 2018: Biotechnology Progress
Agnieszka Kołodziejczak-Radzimska, Jakub Zdarta, Teofil Jesionowski
Acylase I from Aspergillus melleus was immobilized on supports consisting of unmodified and modified silica. Modification was performed using 3-aminopropyltriethoxysilane (APTES) and glutaraldehyde (GA). The effectiveness of immobilization was investigated using the standard Bradford method in addition to a number of physicochemical techniques, including spectroscopic methods (FTIR, 29 Si and 13 C CP MAS NMR), porous structure and elemental analysis, and zeta potential measurement. A determination of catalytic activity was made based on the deacetylation reaction of N-acetyl-l-methionine...
January 8, 2018: Biotechnology Progress
Jian Dong, Kun-Qiang Hong, Ai-Li Hao, Cui-Ying Zhang, Xiao-Meng Fu, Peng-Fei Wang, Dong-Guang Xiao
As content and proportion of ethyl acetate is critical to the flavor and quality of beverages, the concise regulation of the ethyl acetate metabolism is a major issue in beverage fermentations. In the present study, for ethyl acetate yield regulation, we finely modulated the expression of ATF1 through precise and seamless insertion of serially truncated PGK1 promoter from the 3'end by 100bp steps in the Chinese liquor yeast, CLy12a. The three engineered promoters carrying 100-, 200- and 300-bp truncations exhibited reduced promoter strength but unaffected growth...
January 5, 2018: Biotechnology Progress
Lu Wang, Xilong Du, YanZhi Feng, Panfeng Liu, Jingle Zhu, Lin Zhang, Hongyan Du, Mingguo Ma, Fangdong Li
The WRINKLED1 (WRI1) gene is a well-established key transcriptional regulator involved in the regulation of fatty acid biosynthesis in developing seeds. In this study, a new WRI1 gene was isolated from seeds of Eucommia ulmoides (E. ulmoides) and named EuWRI1. A close link between gibberellins (GA) signaling and EuWRI1 gene expression was suggested in this study. Functional characterization of EuWRI1 was elucidated through seed-specific expression in tobacco. In transgenic tobacco, the expression of EuWRI1 in eight independent transgenic lines was detected by semi-quantitative RT-PCR...
January 5, 2018: Biotechnology Progress
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