Read by QxMD icon Read

Bioprocess and Biosystems Engineering

Xiaohui Zhao, Fuqiang Fan, Huaidong Zhou, Panwei Zhang, Gaofeng Zhao
In-depth understanding of indigenous microbial assemblages resulted from aged contamination by polycyclic aromatic hydrocarbons (PAHs) is of vital importance in successful in situ bioremediation treatments. Soil samples of three boreholes were collected at 12 different vertical depths. Overall, the dominating three-ring PAHs (76.2%) were closely related to distribution patterns of soil dehydrogenase activity, microbial cell numbers, and Shannon biodiversity index (H') of indigenous microorganisms. High-molecular-weight PAHs tend to yield more diverse communities...
March 15, 2018: Bioprocess and Biosystems Engineering
Anna-Lena Heins, Dirk Weuster-Botz
Population heterogeneity is omnipresent in all bioprocesses even in homogenous environments. Its origin, however, is only so well understood that potential strategies like bet-hedging, noise in gene expression and division of labour that lead to population heterogeneity can be derived from experimental studies simulating the dynamics in industrial scale bioprocesses. This review aims at summarizing the current state of the different parts of single cell studies in bioprocesses. This includes setups to visualize different phenotypes of single cells, computational approaches connecting single cell physiology with environmental influence and special cultivation setups like scale-down reactors that have been proven to be useful to simulate large-scale conditions...
March 14, 2018: Bioprocess and Biosystems Engineering
Nestor D Ortega-de la Rosa, Jose L Vázquez-Vázquez, Sergio Huerta-Ochoa, Miquel Gimeno, Mariano Gutiérrez-Rojas
Acinetobacter species are identified as producing surface-active and emulsifying molecules known as bioemulsifiers. Production, characterization and stability of bioemulsifiers produced by Acinetobacter bouvetii UAM25 were studied. A. bouvetii UAM25 grew in three different carbon and energy sources: ethanol, a glycerol-hexadecane mixture and waste cooking oil in an airlift bioreactor, showing that bioemulsifier production was growth associated. The three purified bioemulsifiers were lipo-heteropolysaccharides of high molecular weight (4866 ± 533 and 462 ± 101 kDa)...
March 14, 2018: Bioprocess and Biosystems Engineering
Heng Dong, Dong Wei, Jinglin Wei, Fei Han, Tao Yan, Malik Saddam Khan, Bin Du, Qin Wei
In present study, the characteristics of soluble microbial products (SMP) were evaluated in aerobic granular sludge system during denitrification process under different chemical oxygen demand/nitrogen (C/N) ratios. Batch experiment showed that the effluent nitrate (NO3 - -N) concentration were 15.24 ± 1.83 and 1.72 ± 1.53 mg/L at C/N ratio of 1 and 6, respectively. For the release of SMP, the protein (PN) and polysaccharide contents increased from 1.23 ± 0.38 and 7.46 ± 1.13 mg/L to 1...
March 9, 2018: Bioprocess and Biosystems Engineering
Karina P Preczeski, Angela B Kamanski, Thamarys Scapini, Aline F Camargo, Tatiani A Modkoski, Vanusa Rossetto, Bruno Venturin, Jéssica Mulinari, Simone M Golunski, Altemir J Mossi, Helen Treichel
In this study, we evaluated the concentration of lipases from Aspergillus niger using efficient and low-cost methods aiming at application in the treatment of waste cooking oils. The change in ionic strength of the medium by the addition of salt and precipitation with ethanol increased the specific activity from 2.90 to 28.50 U/mg, resulting in a purification factor of 9.82-fold. The use of acetone resulted in a specific activity of 33.63 U/mg, resulting in a purification factor of 11.60-fold. After that, the concentrated lipase was used in the hydrolysis of waste cooking oil and 753...
March 7, 2018: Bioprocess and Biosystems Engineering
Xiao Li, Chao-Qun Xu, Yu-Di Luo, Song Zhang, Cong Huang, Kun Zou, Ya-Li Tan, Ye-Xu Wu, Zhang-Shuang Deng
The computational fluid dynamics (CFD) software package Fluent was utilized to simulate the flow field of Escherichia coli (E. coli) BL21 fermentation in a 50 L automatic bioreactor for producing α-cyclodextrin glycosyltransferase (α-CGTase) in this study. 4-down-pumping propeller (4DPP), 6-curved-blade disc turbine (6CBDT), and Rushton turbine (RT) were assembled to form eight impeller combinations (C1-C8). Through flow field simulating, four referential impeller combinations, in which C6, C7, and C8 were three layers stirring blades and C1 as a control, were selected to carry out batch fermentation experiments (TC1, TC6, TC7, and TC8) for validation...
March 6, 2018: Bioprocess and Biosystems Engineering
Dongmei Zhang, Shumei Wen, Xia Wu, Wei Cong
To overcome the contamination in open pond, microalgal strain selection should focus on species with tolerability to extreme environments. In this study, a native alkaliphilic algae, diatom Nitzschia plea was obtained in Southeast of China, which could tolerate high concentration of NaHCO3 (0.15 mol/L) and high pH (> 10). The effects of initial pH, light intensity and temperature on cell growth, biochemical composition and fatty acid profile of N. plea were investigated. Results indicated its specific growth rate could reach 1...
March 5, 2018: Bioprocess and Biosystems Engineering
Chang-Ho Cho, Won-Sub Shin, Do-Wook Woo, Jong-Hee Kwon
Aurantiochytrium can produce significant amounts of omega-3 fatty acids, specifically docosahexaenoic acid and docosapentaenoic acid. Use of a glucose-based medium for heterotrophic growth is needed to achieve a high growth rate and production of abundant lipids. However, heat sterilization for reliable cultivation is not appropriate to heat-sensitive materials and causes a conversion of glucose via browning (Maillard) reactions. Thus, the present study investigated the use of a direct degradation of Peracetic acid (PAA) for omega-3 production by Aurantiochytrium...
March 3, 2018: Bioprocess and Biosystems Engineering
Xun He, Feng He, Jiao Hang, Hui Li, Yali Chen, Ping Wei, Kequan Chen, Yan Li, Pingkai OuYang
Industrial grade soluble corn starch was used directly and effectively as the fermentation substrate for microbial exopolysaccharides production. Bacillus subtilis mutant strain NJ308 grew with untreated starch raw material as the sole carbon source. The real-time PCR results demonstrated that up-regulated genes encoding N-acetylglucosaminyltransferase, mannosyltransferase, and N-acetylglucosamine-1-phosphate uridyltransferase were the key elements of B. subtilis mutant strain NJ308 for exopolysaccharides production from industrial grade starch...
March 2, 2018: Bioprocess and Biosystems Engineering
Renu Singh, Anirban Banerjee, Praveen Kaul, Brajesh Barse, U C Banerjee
In the original version of our paper entitled "Release of an enantioselective nitrilase from Alcaligenes faecalis MTCC 126: a comparative study" (2005) 27:415-424, some references to already published articles were inadvertently left out.
February 24, 2018: Bioprocess and Biosystems Engineering
F Kashanian, M M Masoudi, A Shamloo, M Habibi-Rezaei, A A Moosavi-Movahedi
Miniaturized systems based on the principles of microfluidics are widely used in various fields, such as biochemical and biomedical applications. Systematic design processes are demanded the proper use of these microfluidic devices based on mathematical simulations. Aggregated proteins (e.g., inclusion bodies) in solution with chaotropic agents (such as urea) at high concentration in combination with reducing agents are denatured. Refolding methods to achieve the native proteins from inclusion bodies of recombinant protein relying on denaturant dilution or dialysis approaches for suppressing protein aggregation is very important in the industrial field...
February 22, 2018: Bioprocess and Biosystems Engineering
Ana Vrsalović Presečki, Lela Pintarić, Anera Švarc, Đurđa Vasić-Rački
The stereoselective three-enzyme cascade for the one-pot synthesis of (1S,2S)-1-phenylpropane-1,2-diol ((1S,2S)-1-PPD) from inexpensive starting substrates, benzaldehyde and acetaldehyde, was explored. By coupling stereoselective carboligation catalyzed by benzoylformate decarboxylase (BFD), L-selective reduction of a carbonyl group with alcohol dehydrogenase from Lactobacillus brevis (ADHLb) as well as the coenzyme regeneration by formate dehydrogenase (FDH), enantiomerically pure diastereoselective 1,2-diol was produced...
February 20, 2018: Bioprocess and Biosystems Engineering
Qian-Qian Tong, Yue-Hui Zhou, Xiang-Song Chen, Jin-Yong Wu, Ping Wei, Li-Xia Yuan, Jian-Ming Yao
The production of virginiamycin (VGM) from Streptomyces virginiae was improved by genome shuffling and ribosome engineering companied with a high-throughput screening method integrating deep-well cultivation and the cylinder-plate detecting. First, a novel high-throughput method was developed to rapidly screen large numbers of VGM-producing mutants. Then, the starting population of genome shuffling was obtained through ultraviolet (UV) and microwave mutagenesis, and four mutants with higher productivity of VGM were selected for genome shuffling...
February 19, 2018: Bioprocess and Biosystems Engineering
Peifei Ding, Weifeng Song, Ziheng Yang, Jingyi Jian
Bacillus vallismortis (B. vallismortis), an aerobic heterotrophic bacteria, was screened in a laboratory pilot study, to assess the interaction between the heavy metal Zn(II) and extracellular polymeric substances (EPS). The influence of Zn(II) stress on EPS production, component variation, and sorption performance, was investigated. The characteristics of B. vallismortis EPS formed under stress were analyzed using FTIR, 3D-EEM and XPS. EPS was used as an adsorbent and the adsorption capacity and adsorption behavior of EPS formed with and without Zn(II) stress, were compared and assessed...
February 17, 2018: Bioprocess and Biosystems Engineering
Minsoo Kwak, Seul Gi Kang, Won-Kyung Hong, Jong-In Han, Yong Keun Chang
Microalgae are regarded as a promising source of biofuels, and the concept of a microalgae-based biorefinery has attracted increasing attention in recent years. From an economic perspective, however, the process remains far from competitive with fossil fuels. This is particularly true of lipid extraction, due in part to the energy-intensive drying step. As a result, wet extraction methods have been studied as an economic alternative. In the present study, a novel extraction approach which utilizes high shear stress mixing was adopted and demonstrated for simultaneous lipid extraction and cell disruption to enable the retrieval of lipids directly from concentrated wet biomass...
February 16, 2018: Bioprocess and Biosystems Engineering
Argang Kazemzadeh, Cynthia Elias, Melih Tamer, Farhad Ein-Mozaffari
The hydrodynamics of gas-liquid two-phase flow in a single-use bioreactor were investigated in detail both experimentally and numerically. Electrical resistance tomography (ERT) and dynamic gas disengagement (DGD) combined with computational fluid dynamics (CFD) were employed to assess the effect of the volumetric gas flow rate and impeller speed on the gas-liquid flow field, local and global gas holdup values, and Sauter mean bubble diameter. From the results obtained from DGD coupled with ERT, the bubble sizes were determined...
February 14, 2018: Bioprocess and Biosystems Engineering
Xiao Liu
Functional porous hollow microspheres with superparamagnetism, Fe3O4/P(GMA-DVB-St) microspheres, were prepared via a dispersion polymerization based on hollow Fe3O4microspheres. The resulting hollow microspheres were characterized by means of Fourier-transform infrared spectrophotometer (FT-IR), X-ray diffraction (XRD), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET) gas sorptometry, and vibrating sample magnetometer (VSM). It is verified that the resulting hollow microspheres are porous and have high saturation magnetization...
February 14, 2018: Bioprocess and Biosystems Engineering
Priscila Marques da Paz, Juliana de Oliveira
This work is based on the importance of monitoring the thermodynamic variables of sugarcane juice fermentation by Saccharomyces cerevisiae, using a numerical technique, and providing artifices that lead to the best performance of this bioprocess. Different combinations of yeast quantity were added to diverse dilutions of cane juice, allowing the evaluation of the fermentation performance. This was conducted by observing the temperature signal obtained from thermal probes inserted in the experimental set up...
February 13, 2018: Bioprocess and Biosystems Engineering
E Tsagkari, W T Sloan
Biofilms are found at the inner surfaces of drinking water pipes and, therefore, it is essential to understand biofilm processes to control their formation. Hydrodynamics play a crucial role in shaping biofilms. Thus, knowing how biofilms form, develop and disperse under different flow conditions is critical in the successful management of these systems. Here, the development of biofilms after 4 weeks, the initial formation of biofilms within 10 h and finally, the response of already established biofilms within 24-h intervals in which the flow regime was changed, were studied using a rotating annular reactor under three different flow regimes: turbulent, transition and laminar...
February 10, 2018: Bioprocess and Biosystems Engineering
Sunil H Koli, Bhavana V Mohite, Rahul K Suryawanshi, Hemant P Borase, Satish V Patil
The development of a safe and eco-friendly method for metal nanoparticle synthesis has an increasing demand, due to emerging environmental and biological harms of hazardous chemicals used in existing nanosynthesis methods. The present investigation reports a rapid one-step, eco-friendly and green approach for the formation of nanosized silver particles (AgNPs) using extracellular non-toxic-colored fungal metabolites (Monascus pigments-MPs). The formation of nanosized silver particles utilizing Monascus pigments was confirmed after exposure of reaction mixture to sunlight, by visually color change and further established by spectrophotometric analysis...
February 10, 2018: Bioprocess and Biosystems Engineering
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"