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排序方式: 共有158条查询结果,搜索用时 31 毫秒
91.
Leasa A Greene Issa Isaac Dean E Gray Sarah A Schwartz 《Journal of biomolecular techniques》2007,18(4):238-244
Several species in the genus Echinacea are beneficial herbs popularly used for many ailments. The most popular Echinacea species for cultivation, wild collection, and herbal products include E. purpurea (L.) Moench, E. pallida (Nutt.) Nutt., and E. angustifolia (DC). Product adulteration is a key concern for the natural products industry, where botanical misidentification and introduction of other botanical and nonbotanical contaminants exist throughout the formulation and production process. Therefore, rapid and cost-effective methods that can be used to monitor these materials for complex product purity and consistency are of benefit to consumers and producers. The objective of this continuing research was to develop automated, high-throughput processing methods that, teamed with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis, differentiate Echinacea species by their mass profiles. Small molecules, peptide, and proteins from aerial parts (leaf/stem/flowers), seeds, and roots from E. purpurea and E. angustifolia; seeds and roots from E. pallida; and off-the-shelf Echinacea supplements were extracted and analyzed by MS using methods developed on the ProPrep liquid handling system (Genomic Solutions). Analysis of these samples highlighted key MS signal patterns from both small molecules and proteins that characterized the individual Echinacea materials analyzed. Based on analysis of pure Echinacea samples, off-the-shelf products containing Echinacea could then be evaluated in a streamlined process. Corresponding analysis of dietary supplements was used to monitor for product composition, including Echinacea species and plant materials used. These results highlight the potential for streamlined, automated approaches for agricultural species differentiation and botanical product evaluation. 相似文献
92.
Nucci ER Silva RG Souza VR Giordano RL Giordano RC Cruz AJ 《Bioprocess and biosystems engineering》2007,30(6):429-438
Penicillin G acylase (PGA) is one of the most important enzymes for the pharmaceutical industry. Bacillus megaterium has the advantage of producing extra-cellular PGA. This work compares two neural networks (NNs) architectures for on-line
inference of B. megaterium cell mass in an aerated stirred tank bioreactor, during the production of PGA. Nowadays, intelligent computing tools such
as artificial NNs and fuzzy logic are commonly applied for state inference and modeling of bioreactors. Combining these two
approaches in hybrid, neuro-fuzzy systems, may be advantageous. Our results indicate that a neuro-fuzzy inference system showed
a better performance to infer cell concentrations, when compared to multilayer perceptrons networks. 相似文献
93.
The pharmaceutical and biotech industries face continued pressure to reduce development costs and accelerate process development. This challenge occurs alongside the need for increased upstream experimentation to support quality by design initiatives and the pursuit of predictive models from systems biology. A small scale system enabling multiple reactions in parallel (n ≥ 20), with automated sampling and integrated to purification, would provide significant improvement (four to fivefold) to development timelines. State of the art attempts to pursue high throughput process development include shake flasks, microfluidic reactors, microtiter plates and small-scale stirred reactors. The limitations of these systems are compared to desired criteria to mimic large scale commercial processes. The comparison shows that significant technological improvement is still required to provide automated solutions that can speed upstream process development. 相似文献
94.
In recent years, several automated scale-down bioreactor systems have been developed to increase efficiency in cell culture process development. ambr™ is an automated workstation that provides individual monitoring and control of culture dissolved oxygen and pH in single-use, stirred-tank bioreactors at a working volume of 10–15 mL. To evaluate the ambr™ system, we compared the performance of four recombinant Chinese hamster ovary cell lines in a fed-batch process in parallel ambr™, 2-L bench-top bioreactors, and shake flasks. Cultures in ambr™ matched 2-L bioreactors in controlling the environment (temperature, dissolved oxygen, and pH) and in culture performance (growth, viability, glucose, lactate, Na+, osmolality, titer, and product quality). However, cultures in shake flasks did not show comparable performance to the ambr™ and 2-L bioreactors. 相似文献
95.
Jefferies J Clarke SC Diggle MA Smith A Dowson C Mitchell T 《Molecular biotechnology》2003,24(3):303-307
Multilocus sequence typing (MLST) is used by the Scottish Meningococcus and Pneumococcus Reference Laboratory (SMPRL) as a
routine method for the characterization of certain bacterial pathogens. The SMPRL recently started performing MLST on strains
of Streptococcus pneumoniae, and here we describe a fully automated method for MLST using a 96-well-format liquid-handling robot and a 96-capillary automated
DNA sequencer. 相似文献
96.
Shih CI 《Experimental & applied acarology》2001,25(5):425-440
Using incorporated devices, Tetranychus urticae spider mites were rinsed from hydroponically-grown lima bean plants, collected, separated and blow-dried. This yielded a reliable and large volume of eggs and larvae, which were fed to Amblyseius womersleyi rearings on 15×5cm2 polyethylene arenas. Of several feeding regimes tested, daily feeding of 10mg T. urticae eggs and larvae resulted in the highest predator population levels. The best harvest period was between 15 and 27 days, when predator density exceeded 600 mites per arena. A preliminary automatic mass-rearing device was tested for A. womersleyi. This incorporated both rearing and harvesting procedures. A micro-feeder was developed to supply the required volume of spider mites and maize pollen (1:1 mixture) to the predators. A Bakelite rearing arena reduced the space requirements of a polyethylene arena, was more durable and an essential component in the automatic mass-rearing and harvesting. Mite harvesting is carried out through the use of a vacuum-head harvester. Supplements of (sterilized) spider mites, pollen, vermiculite and wheat bran are automatically added to the predators. The devices for harvesting, filling and packing are incorporated and synchronized and the entire system is controlled by a single slide-switch. The design and system can be expanded without changing the basic processes and program, for example to adopt it for other species of predaceous mites. 相似文献
97.
Apweiler R 《Briefings in bioinformatics》2001,2(1):9-18
With the rapid growth of sequence databases, there is an increasing need for reliable functional characterisation and annotation of newly predicted proteins. To cope with such large data volumes, faster and more effective means of protein sequence characterisation and annotation are required. One promising approach is automatic large-scale functional characterisation and annotation, which is generated with limited human interaction. However, such an approach is heavily dependent on reliable data sources. The SWISS-PROT protein sequence database plays an essential role here owing to its high level of functional information. 相似文献
98.
Akutsu J Tojo Y Segawa O Obata K Okochi M Tajima H Yohda M 《Biotechnology and bioengineering》2004,86(6):667-671
We have developed an integrated automation system for genetic analysis and gene manipulation. The system, SX-8G Plus, is equipped with an 8-nozzle dispensing unit, a thermal cycler, a cooled reagent reservoir, four tip storage racks, four microplate platforms, buffer reservoirs, an agarose gel electrophoresis unit, a power supply, a pump for exchanging electrophoresis buffer, and a CCD camera. Automation of nucleic acid extraction and purification, the most difficult step in automating genetic analysis and gene manipulation, was realized using magnetic beads with Magtration Technology, which we have previously developed for automating the handling of paramagnetic beads. Using this system, we could perform the automated separation and purification of DNA fragments by agarose gel electrophoresis starting from sample loading. The system would enable the automation of almost all procedures in genetic analysis and gene manipulation. 相似文献
99.
Gao X Bain K Bonanno JB Buchanan M Henderson D Lorimer D Marsh C Reynes JA Sauder JM Schwinn K Thai C Burley SK 《Journal of structural and functional genomics》2005,6(2-3):129-134
High-resolution structural information is important for improving our understanding of protein function in vitro and in vivo and providing information to enable drug discovery. The process leading to X-ray structure determination is often time consuming
and labor intensive. It requires informed decisions in expression construct design, expression host selection, and strategies
for protein purification, crystallization and structure determination. Previously published studies have demonstrated that
compact globular domains defined by limited proteolysis represent good candidates for production of diffraction quality crystals
[1–7]. Integration of mass spectrometry and proteolysis experiments can provide accurate definition of domain boundaries at
unprecedented rates. We have conducted a critical evaluation of this approach with 400 target proteins produced by SGX (Structural
GenomiX, Inc.) for the New York Structural GenomiX Research Consortium (NYSGXRC; ) under the auspices of the National Institute of General Medical Sciences Protein Structure Initiative (). The objectives of this study were to develop parallel/automated protocols for proteolytic digestion and data acquisition
for multiple proteins, and to carry out a systematic study to correlate domain definition via proteolysis with outcomes of crystallization and structure determination attempts. Initial results from this work demonstrate
that proteins yielding diffraction quality crystals are typically resistant to proteolysis. Large-scale sub cloning and subsequent
testing of expression, solubility, and crystallizability of proteolytically defined truncations is currently underway. 相似文献
100.
A novel milliliter-scale bioreactor equipped with a gas-inducing impeller was developed with oxygen transfer coefficients as high as in laboratory and industrial stirred-tank bioreactors. The bioreactor reaches oxygen transfer coefficients of >0.4 s(-1). Oxygen transfer coefficients of >0.2 s(-1) can be maintained over a range of 8- to 12-mL reaction volume. A reaction block with integrated heat exchangers was developed for 48-mL-scale bioreactors. The block can be closed with a single gas cover spreading sterile process gas from a central inlet into the headspace of all bioreactors. The gas cover simultaneously acts as a sterile barrier, making the reaction block a stand-alone device that represents an alternative to 48 parallel-operated shake flasks on a much smaller footprint. Process control software was developed to control a liquid-handling system for automated sampling, titration of pH, substrate feeding, and a microtiter plate reader for automated atline pH and atline optical density analytics. The liquid-handling parameters for titration agent, feeding solution, and cell samples were optimized to increase data quality. A simple proportional pH-control algorithm and intermittent titration of pH enabled Escherichia coli growth to a dry cell weight of 20.5 g L(-1) in fed-batch cultivation with air aeration. Growth of E. coli at the milliliter scale (10 mL) was shown to be equivalent to laboratory scale (3 L) with regard to growth rate, mu, and biomass yield, Y(XS). 相似文献