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Bioprocess and Biosystems Engineering

Diana Ivonne Franco-Medrano, Patricia Guerrero-Germán, Rosa María Montesinos-Cisneros, Jaime Ortega-López, Armando Tejeda-Mansir
The demand for plasmid DNA (pDNA) has increased in response to the rapid advances in vaccines applications to prevent and treat infectious diseases caused by virus, bacteria or parasites, such as Leishmania species. The immunization protocols require large amounts of supercoiled plasmid DNA (sc-pDNA) challenging the development of efficient and profitable processes for capturing and purified pDNA molecules from large volumes of lysates. A typical bioprocess involves four steps: fermentation, primary recovery, intermediate recovery and final purification...
December 2, 2016: Bioprocess and Biosystems Engineering
Marcos Camargo Knirsch, Filippo Dell'Anno, Marco Salerno, Claudio Larosa, Bronislaw Polakiewicz, Roberto Eggenhöffner, Attilio Converti
Polyhemoglobin produced from pure bovine hemoglobin by reaction with PEG bis(N-succynimidil succinate) as a cross-linking agent was encapsulated in gelatin and dehydrated by freeze-drying. Free carboxyhemoglobin and polyhemoglobin microcapsules were characterized by UV-Vis spectroscopy in the absorption range 450-650 nm and cyclic voltammetry in the voltage range from -0.8 to 0.6 mV to evaluate the ability to break the bond with carbon monoxide and to study the carrier's affinity for oxygen, respectively...
December 1, 2016: Bioprocess and Biosystems Engineering
Faiza Shahid, Afsheen Aman, Muhammad Asif Nawaz, Asad Karim, Shah Ali Ul Qader
Dextranase is a unique biocatalyst that has high specificity and stereo-selectivity towards a complex biopolymer known as dextran. Dextranase has wide industrial application, but most of the time harsh environmental conditions adversely affect the functionality and stability of the enzyme. To overcome this issue, a covalent cross-linking immobilization method was adapted in the current study utilizing a nontoxic and biocompatible matrix known as chitosan. Chitosan hydrogel microspheres were synthesized using chitosan which exhibited noteworthy physical and mechanical strength...
November 30, 2016: Bioprocess and Biosystems Engineering
So-Young Jun, Sung Ho Kim, Bashista Kumar Kanth, Jinwon Lee, Seung Pil Pack
The CO2 mineralization process, accelerated by carbonic anhydrase (CA) was proposed for the efficient capture and storage of CO2, the accumulation of which in the atmosphere is the main cause of global warming. Here, we characterize a highly stable form of the cloned CA from the Gram-negative marine bacterium Aliivibrio salmonicida, named ASCA that can promote CO2 absorption in an alkaline solvent required for efficient carbon capture. We designed a mature form of ASCA (mASCA) using a codon optimization of ASCA gene and removal of ASCA signal peptide...
November 28, 2016: Bioprocess and Biosystems Engineering
Jian-Ying Dai, Lin-Hui Ma, Zhuang-Fei Wang, Wen-Tian Guan, Zhi-Long Xiu
Acetoin is a natural flavor and an important bio-based chemical which could be separated from fermentation broth by solvent extraction, salting-out extraction or recovered in the form of derivatives. In this work, a novel method named as sugaring-out extraction coupled with fermentation was tried in the acetoin production by Bacillus subtilis DL01. The effects of six solvents on bacterial growth and the distribution of acetoin and glucose in different solvent-glucose systems were explored. The operation parameters such as standing time, glucose concentration, and volume ratio of ethyl acetate to fermentation broth were determined...
November 23, 2016: Bioprocess and Biosystems Engineering
Tomas Humhal, Petr Kastanek, Zuzana Jezkova, Anna Cadkova, Jana Kohoutkova, Tomas Branyik
Saline waste water from demineralization of cheese whey was used as the main component of waste saline medium (WSM) for cultivation of thraustochytrids. The suitability of WSM for cultivation of Schizochytrium limacinum PA-968 and Japonochytrium marinum AN-4 was evaluated by comparison with cultivation on nutrient medium (NM) in shake flask and fermenter cultures. Biomass productivities achieved in WSM for the thraustochytrids were comparable with those in NM for both shake flask and fermenter cultures. The maximum total lipid content (56...
November 23, 2016: Bioprocess and Biosystems Engineering
Chae Hun Ra, Gwi-Taek Jeong, Sung-Koo Kim
Optimal hyper-thermal (HT) acid hydrolysis conditions for Gelidium amansii were determined to be 12% (w/v) seaweed slurry content and 144 mM H2SO4 at 150 °C for 10 min. HT acid hydrolysis-treated G. amansii hydrolysates produced low concentrations of inhibitory compounds and adsorption treatment using 3% activated carbon. An adsorption time of 5 min was subsequently used to remove the inhibitory 5-hydroxymethylfurfural from the medium. A final maximum monosaccharide concentration of 44.6 g/L and 79.1% conversion from 56...
November 22, 2016: Bioprocess and Biosystems Engineering
Jian Cheng, Wei Zhuang, Chenglun Tang, Yong Chen, Jinglan Wu, Ting Guo, Hanjie Ying
N-Acetylglucosamine-2-epimerase (AGE) and N-acetylneuraminic acid lyase (NAL) were immobilized for synthesis of N-acetylneuraminic acid (Neu5Ac) on three resins: Amberzyme oxirane resin (AOR), poly (styrene-co-DVB)-Br resin (PBR) and amino resin (AR). The loading capacity and immobilized enzyme activity showed that AR was the best carrier. Three methods of glutaraldehyde cross-linking were tested and simultaneous cross-linking and immobilization was demonstrated to be the best method. The functional properties of immobilized AGE and NAL were studied and compared to those of the free enzyme...
November 15, 2016: Bioprocess and Biosystems Engineering
Chae Hun Ra, Min Ji Kim, Gwi-Taek Jeong, Sung-Koo Kim
A total monosaccharide concentration of 37.8 g/L and 85.9% conversion from total fermentable monosaccharides of 44.0 g/L from 110 g dw/L Eucheuma denticulatum slurry were obtained by thermal acid hydrolysis and enzymatic saccharification. Subsequent adsorption treatment to remove 5-hydroxymethylfurfural (5-HMF) using 5% activated carbon and an adsorption time of 10 min were used to prevent a prolonged lag phase, reduced cell growth, and low ethanol production. The equilibrium adsorption capacity (q e) of HMF (58...
November 9, 2016: Bioprocess and Biosystems Engineering
Wenbing Wang, Yanqing Wu, Chi Zhang
Anaerobic microorganisms were applied to degrade organic contaminants in groundwater with permeable reactive barriers (PRBs). However, anaerobic microorganisms need to select optimal immobilizing material as carrier. The potential of high-density natural luffa sponge (HDLS) (a new variety of luffa) for the immobilization and protection of anaerobic microorganisms was investigated. The HDLS has a dense structure composed of a complicated interwoven fibrous network. Therefore, the abrasion rate of HDLS (0.0068 g s(-1)) was the smallest among the four carriers [HDLS, ordinary natural luffa sponge (OLS), polyurethane sponge (PS), and gel carrier AQUAPOROUSGEL (APG)]...
November 9, 2016: Bioprocess and Biosystems Engineering
Joy Sarkar, Md Masud Rahaman Mollick, Dipankar Chattopadhyay, Krishnendu Acharya
In recent times, biosynthetic approaches toward the synthesis of nanoparticles have been shown to have several advantages over physical and chemical methods. Here, we report the extracellular mycosynthesis of γ-Fe2O3 nanoparticles by Alternaria alternata. The fungal biomass when exposed to aqueous iron(III) chloride solution led to the formation of highly stable γ-Fe2O3 nanoparticles extracellularly. The influence of these biosynthesized γ-Fe2O3 nanoparticles on the properties of hydroxyl propyl methyl cellulose was also investigated...
November 8, 2016: Bioprocess and Biosystems Engineering
L André, A Pauss, T Ribeiro
The chemical oxygen demand (COD) is an essential parameter in waste management, particularly when monitoring wet anaerobic digestion processes. An adapted method to determine COD was developed for solid waste (total solids >15%). This method used commercial COD tubes and did not require sample dilution. A homemade plastic weighing support was used to transfer the solid sample into COD tubes. Potassium hydrogen phthalate and glucose used as standards showed an excellent repeatability. A small underestimation of the theoretical COD value (standard values around 5% lower than theoretical values) was also observed, mainly due to the intrinsic COD of the weighing support and to measurement uncertainties...
November 4, 2016: Bioprocess and Biosystems Engineering
Na Wu, Dong Wei, Yongfang Zhang, Weiying Xu, Tao Yan, Bin Du, Qin Wei
The objective of this study was to compare the release of soluble microbial products (SMP) from activated sludge (AS) and aerobic granular sludge (AGS) in the absence and presence of 2,4-dichlorophenol (2,4-DCP). Data implied that NH4(+)-N removal efficiencies remarkably decreased to 53.8% and 36.4% after the addition of 2,4-DCP, respectively. Three-dimensional excitation-emission matrix (3D-EEM) implied that three major components (tryptophan protein-like, humic-like and fulvic-like substances) were identified in SMP without the addition of 2,4-DCP...
November 3, 2016: Bioprocess and Biosystems Engineering
Liang Wang, Xusheng Chen, Guangyao Wu, Shu Li, Xin Zeng, Xidong Ren, Lei Tang, Zhonggui Mao
ε-Poly-L-lysine (ε-PL), as a food additive, has been widely used in many countries. However, its production still needs to be improved. We successfully enhanced ε-PL production of Streptomyces albulus FEEL-1 by introducing mutations related to antibiotics, such as streptomycin, gentamicin, and rifampin. Single- and double-resistant mutants (S-88 and SG-31) were finally screened with the improved ε-PL productions of 2.81 and 3.83 g/L, 1.75- to 2.39-fold compared with that of initial strain FEEL-1. Then, the performances of mutants S-88 and SG-31 were compared with the parent strain FEEL-1 in a 5-L bioreactor under the optimal condition for ε-PL production...
November 2, 2016: Bioprocess and Biosystems Engineering
Hongmei Jin, Caiyun Xu, Jing Du, Huashan Wu, Hongying Huang, Zhizhou Chang, Yueding Xu, Lixiang Zhou
The effects of hydraulic retention time (20 and 15 days) and swine manure to rice straw ratios on distribution of sulfonamides (SAs) in liquid and solid anaerobic digestates were studied using bench-scale completely stirred tank reactors at (37 ± 1) °C. Results showed that anaerobic digestion (AD) treatment exhibited a good removal effect on sulfadiazine (SDZ), sulfadimidine (SM2) and sulfachloropyridazine (SCP), especially at HRT = 20 days and co-digestion with swine manure and rice straw. The removal rates of SDZ and SM2 were more than 90%, but only 72...
October 31, 2016: Bioprocess and Biosystems Engineering
Balaji Balagurunathan, Vishist Kumar Jain, Crystal Jing Ying Tear, Chan Yuen Lim, Hua Zhao
Integrated approaches using in silico model-based design and advanced genetic tools have enabled efficient production of fuels, chemicals and functional ingredients using microbial cell factories. In this study, using a recently developed genome-scale metabolic model for Escherichia coli iJO1366, a mutant strain has been designed in silico for the anaerobic growth-coupled production of a simple polyol, glycerol. Computational complexity was significantly reduced by systematically reducing the target reactions used for knockout simulations...
October 28, 2016: Bioprocess and Biosystems Engineering
Mengmeng Huang, Yanyun Gao, Xiangshan Zhou, Yuanxing Zhang, Menghao Cai
Unfolded protein response (UPR) usually happens when expressing heterologous proteins in high level, which may help cells to facilitate protein processing. Here, we evaluated the effects of the UPR activator HAC1p on a raw-starch hydrolyzing α-amylase (Gs4j-amyA), so as to improve heterologous production of the enzyme in Pichia pastoris. The gene (amyA) encoding Gs4j-amyA was first codon-optimized and expressed in P. pastoris under the control of the AOX1 promoter. A high gene dosage (12 copies) of amyA facilitated amylase expression which produced an enzyme activity of 305 U/ml...
October 28, 2016: Bioprocess and Biosystems Engineering
M Mahmoodi, G D Najafpour, M Mohammadi
In this article, availability and control of water in solid-state fermentation (SSF) were investigated. Based on passive transport of water through plasma membranes, a new model was proposed for calculation and control of water activities in the mixture of solids. The validity of theoretical model and accuracy of the proposed model were proved by experimental data. This model was used for production of pectinases via mixed-SSF with the aid of a rotary drum bioreactor. It was found that in case of extracellular enzyme production, the new model is in good agreement with experimental data for the control of water activities in the mixed-SSF...
October 24, 2016: Bioprocess and Biosystems Engineering
Lin Li, Kaixiong Yang, Jian Lin, Junxin Liu
An integrated-bioreactor, which consisted of a suspended zone and an immobilized zone, was applied to treat gases containing SO2. The removal of SO2 in suspended zone differed slightly from that in immobilized zone. The influences of operational aspects such as SO2 load, temperature, and pH on integrated-bioreactor performance and bacterial community composition were investigated. The synergistic action of the two zones led to effective reduction of SO2, and the total removal efficiencies with the inlet concentration of 91-117 mg/m(3), were over 85 % in steady state...
October 21, 2016: Bioprocess and Biosystems Engineering
Qingqi Yan, Yumei Wang, Wawat Rodiahwati, Antje Spiess, Michael Modigell
Screw press processing of biomass can be considered as a suitable mechanically based pretreatment for biofuel production since it disrupts the structure of lignocellulosic biomass with high shear and pressure forces. The combination with chemical treatment has been suggested to increase the conversion of lignocellulosic biomass to fermentable sugars. Within the study, the synergetic effect of alkaline (sodium hydroxide, NaOH) soaking and screw press pretreatment on wheat straw was evaluated based on, e.g., sugar recovery and energy efficiency...
October 19, 2016: Bioprocess and Biosystems Engineering
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