Abstract:
:Nitrifying bacteria, cyanobacteria, and algae are important microorganisms in open pond wastewater treatment systems. Nitrification involving the sequential oxidation of ammonia to nitrite and nitrate, mainly due to autotrophic nitrifying bacteria, is essential to biological nitrogen removal in wastewater and global nitrogen cycling. A continuous flow autotrophic bioreactor was initially designed for nitrifying bacterial growth only. In the presence of cyanobacteria and algae, we monitored both the microbial activity by measuring specific oxygen production rate (SOPR) for microalgae and cyanobacteria and specific oxygen uptake rate (SOUR) for nitrifying bacteria. The growth of cyanobacteria and algae inhibited the maximum nitrification rate by a factor of 4 although the ammonium nitrogen fed to the reactor was almost completely removed. Terminal restriction fragment length polymorphism (T-RFLP) analysis indicated that the community structures of nitrifying bacteria remained unchanged, containing the dominant Nitrosospira, Nitrospira, and Nitrobacter species. PCR amplification coupled with cloning and sequencing analysis resulted in identifying Chlorella emersonii and an uncultured cyanobacterium as the dominant species in the autotrophic bioreactor. Notwithstanding their fast growth rate and their toxicity to nitrifiers, microalgae and cyanobacteria were more easily lost in effluent than nitrifying bacteria because of their poor settling characteristics. The microorganisms were able to grow together in the bioreactor with constant individual biomass fractions because of the uncoupled solids retention times for algae/cyanobacteria and nitrifiers. The results indicate that compared to conventional wastewater treatment systems, longer solids retention times (e.g., by a factor of 4) should be considered in phototrophic bioreactors for complete nitrification and nitrogen removal.
journal_name
Biotechnol Bioengjournal_title
Biotechnology and bioengineeringauthors
Choi O,Das A,Yu CP,Hu Zdoi
10.1002/bit.22860subject
Has Abstractpub_date
2010-12-15 00:00:00pages
1004-11issue
6eissn
0006-3592issn
1097-0290journal_volume
107pub_type
杂志文章abstract::A facile methodology has been developed for covalently derivatizing the surfaces of common materials with a designed antibacterial polycation, poly(vinyl-N-pyridinium bromide), wherein the first, key step involves surface coating with a nanolayer of silica. Various commercial synthetic polymers derivatized in this man...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10299
更新日期:2002-08-20 00:00:00
abstract::Dihydrofolate reductase (DHFR) system is used to amplify the product gene to multiple copies in Chinese Hamster Ovary (CHO) cells for generating cell lines which produce the recombinant protein at high levels. The physiological changes accompanying the transformation of the non-protein secreting host cells to a high p...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.25117
更新日期:2014-03-01 00:00:00
abstract::Natural oxygen gradients occur in tissues of biological organisms and also in the context of three-dimensional (3D) in vitro cultivation. Oxygen diffusion limitation and metabolic oxygen consumption by embedded cells produce areas of hypoxia in the tissue/matrix. However, reliable systems to detect oxygen gradients an...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.27503
更新日期:2020-07-15 00:00:00
abstract::Shake flask and stirred tank bioleaching experiments showed that the dissolution of chalcopyrite is inhibited by ferric ion concentrations as low as 200 mg L(-1) and redox potentials >420 mV (vs. Ag/AgCl). Chemical leaching of chalcopyrite (4% suspension, surface area 2.3 m2 g(-1)) was enhanced fourfold in the presenc...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10184
更新日期:2002-05-20 00:00:00
abstract::Short-chain carboxylic acids generated by various mixed- or pure-culture fermentation processes have been considered valuable precursors for production of bioalcohols. While conversion of carboxylic acids into alcohols is routinely performed with catalytic hydrogenation or with strong chemical reducing agents, here, a...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.24786
更新日期:2013-04-01 00:00:00
abstract::A modified mixing plane approach for steady state simulation of flow field in fully baffled biological reactor is presented and discussed. Without requiring any experimental input, this approach of dividing the vessel into suitable number of connected and disconnected zones; solving steady state equation separately in...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.21030
更新日期:2006-11-05 00:00:00
abstract::A simple feeding strategy was developed and successfully employed for nutritional control in a 2-L fed-batch culture of hybridoma cells. A previously developed stoichiometric model for animal cell growth was used to design a supplemental medium for feeding. Undialyzed fetal bovine serum and trace metals (Fe(2+), SeO(3...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/(SICI)1097-0290(19960920)51:6<725::AID-BIT
更新日期:1996-09-20 00:00:00
abstract::A detailed mechanistic model of enzymatic cellulose hydrolysis has been developed. The behavior of individual cellulase enzymes and parameters describing the cellulose surface properties are included. Results obtained for individual enzymes (T. reesei endoglucanase 2 and cellobiohydrolase I) and systems with both enzy...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.22789
更新日期:2010-09-01 00:00:00
abstract::The mouse mammary tumor virus (MMTV) promoter is induced by the addition of a glucocorticoid hormone or analog such as dexamethasone. The hormone binds to its specific transcription factor, glucocorticoid receptor (GR), and the activated complex then binds to the glucocorticoid response elements (GREs) in the enhancer...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:
更新日期:2000-01-20 00:00:00
abstract::Control of cell shape and behavior through the micropattern technique by spatial immobilization of adhesive proteins on a surface has provided novel insights in several aspects of cell biology, such as tissue morphogenesis, cell growth and cell differentiation, and apoptosis. In this work, we present the use of poly(e...
journal_title:Biotechnology and bioengineering
pub_type: 信件
doi:10.1002/bit.22997
更新日期:2011-04-01 00:00:00
abstract::Fibrous proteins, such as silk, elastin and collagen are finding broad impact in biomaterial systems for a range of biomedical and industrial applications. Some of the key advantages of biosynthetic fibrous proteins compared to synthetic polymers include the tailorability of sequence, protein size, degradation pattern...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章,评审
doi:10.1002/bit.25820
更新日期:2016-05-01 00:00:00
abstract::The Model presented in this work demonstrates the combination of cell-cycle model with a model describing the growth and conversion kinetics of hybridoma cells in a steady-state continuous culture. The cell-cycle model is based upon a population balance model as described by Cazzador et al. and assumes the existence o...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260480109
更新日期:1995-10-05 00:00:00
abstract::A method for purifying alpha-amylase inhibitor from wheat meal based on immobilized metal affinity with a thermosensitive copolymer is developed. The studies represent the thermoprecipitation properties of the copolymers of N-isopropylacrylamide (NIPAM) with iminodiacetic acid (IDA) and 1-vinylimidazole (VI), respecti...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/(sici)1097-0290(19980920)59:6<695::aid-bit
更新日期:1998-09-20 00:00:00
abstract::For clinical trials, large amounts of high-titer retroviral supernatants are required. However, retroviral concentration is relatively low compared with other viral vectors. Moreover, less than half of retroviral vectors suspended in a collected supernatant are infectious because of their short half-lives. In this stu...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.20435
更新日期:2005-05-05 00:00:00
abstract::The efficiency of lgM production by hybridoma cells (1) cultured in suspension; (2) entrapped in alginate beads; or (3) packed in hollowfiber cartridge bioreactors, were compared in long-term perfusion cultures. The results showed that steady-state cell concentration and antibody production, per liter of perfused medi...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260400105
更新日期:1992-06-05 00:00:00
abstract::A MATLAB-based program was developed to simulate the distributions of states and behaviors of microbial storage product-accumulating bacteria in suspended growth systems. Currently available computer simulators of these systems predict dynamic behaviors by numerically solving differential biokinetic equations using av...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.20484
更新日期:2005-07-05 00:00:00
abstract::Metabolite accumulation has pleiotropic, toxic, or beneficial effects on cell physiology, but such effects are not well understood at the molecular level. Cells respond and adapt to metabolite stress by mechanisms largely unexplored, especially in the context of multiple and simultaneous stresses. Solventogenic and re...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.22628
更新日期:2010-04-15 00:00:00
abstract::Saccharomyces cerevisiae is a widely used host organism for the production of heterologous proteins, often cultivated in glucose-based fed-batch processes. This production system however has many factors limiting the productivity, mainly towards the end of the fermentation. For the optimised production of a Camelid an...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.21150
更新日期:2007-02-15 00:00:00
abstract::Hydrogel membranes have been fabricated that incorporate antibody/antigen moieties. The permeability of large solutes through these membranes is dependent on the presence of soluble antigen that can compete with the internal interactions between antibody and antigen leading to an increase in gel mesh size. Specificall...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.21255
更新日期:2007-07-01 00:00:00
abstract::This paper presents a new formulation for the analysis of growth kinetics on multiple nutrients. The baseline for the theory is the concept that a noninteractive growth process occurs among perfectly substitutable nutrients if the locus of points of the substrate concentrations producing equal growth rate is linear. A...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260440203
更新日期:1994-06-20 00:00:00
abstract::Pseudomonas putida cells were grown in confined volumes in dual-membrane immobilized cell reactors constructed from microporous polyethylene hollow fibers and silicone rubber tubules as a model system for the study of mass transport in microbial aggregates. Local cell concentrations in the reactors reached 300 g dry m...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260340307
更新日期:1989-07-01 00:00:00
abstract::During lignocellulosic ethanol fermentation, yeasts are exposed to various lignocellulose-derived inhibitors, which disrupt the efficiency of hexose and pentose co-fermentation. To understand the metabolic response of fermentation microbes to these inhibitors, a comparative metabolomic investigation was performed on a...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.24992
更新日期:2014-01-01 00:00:00
abstract::To alleviate plasmid instability and to prolong the production phase of subtilisin, integrable plasmid and spore mutants are used. Compared with batch-type shake flask cultures, spore mutants' ability to produce subtilisin can be well pronounced in fed-batch and continuous cultures. Hence, the two culture methods make...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260470610
更新日期:1995-09-20 00:00:00
abstract::Enzymatic depolymerization of polysaccharides with alpha-amylase has been studied in mixed aqueous dimethylsulfoxide (DMSO)/water solvents. Polysaccharide substrate chemical compositions, configurational structures, and bonding pattersn are known to affect observed enzymatic reaction kinetics. The branching structures...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260460106
更新日期:1995-04-05 00:00:00
abstract::Two kinds of disposable bioreactors, air-lift disposable bioreactors (ADB) and wave disposable bioreactors (WDB) were compared with stirred-tank reactors (5-L STR). These bioreactors were successfully applied to transgenic rice cell cultures for the production of recombinant human cytotoxic T-lymphocyte antigen 4-immu...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.24916
更新日期:2013-09-01 00:00:00
abstract::Among the host of substratum properties that affect animal cell behavior, surface morphology has received relatively little attention. The earliest effect of surface morphology on animal cells was discovered almost a century ago when it was found that cells became oriented in response to the underlying topography. Thi...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260430811
更新日期:1994-04-05 00:00:00
abstract::After separation by microscale non-denaturing two-dimensional gel electrophoresis (2DE) and transferring to a blotting membrane, major proteins are detected by a staining of direct blue 71 in a neutral solution. The carboxylesterase on the membrane hydrolyzes phosphatidylcholine after the spot of carboxylesterase is e...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.21437
更新日期:2007-11-01 00:00:00
abstract::The effect of trehalose (0.5 M) on the thermal stability of cutinase in the alkaline pH range was studied. The thermal unfolding induced by increasing temperature was analyzed in the absence and in the presence of trehalose according to a two-state model (which assumes that only the folded and unfolded states of cutin...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/1097-0290(20001220)70:6<699::aid-bit13>3.0
更新日期:2000-12-20 00:00:00
abstract::Axial and radial oxygen depletion are believed to be critical scale-limiting factors in the design of cell culture hollow fiber bioreactors. A mathematical analysis of oxygen depletion has been performed in order to develop effectiveness factor plots to aid in the scaling of hollow fiber bioreactors with cells immobil...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260370112
更新日期:1991-01-05 00:00:00
abstract::The goal of drug delivery is to improve the safety and therapeutic efficacy of drugs. This review focuses on delivery platforms that are either derived from endogenous pathways, long-circulating biomolecules and cells or that piggyback onto long-circulating biomolecules and cells. The first class of such platforms is ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章,评审
doi:10.1002/bit.25307
更新日期:2014-09-01 00:00:00