Product Quantification

Rapid quantification of products and substrates in a fermentation process is essential for process development and optimization. Most fermentation laboratories have access to HPLC equipment with possibilities to couple them to quite inexpensive diode-array-detectors, and this equipment could be used for quantitative monitoring of the process. Because HPLC can allow multi-component analyses, i.e., several analytes in the same sample can be determined virtually simultaneously, and since it is often necessary to monitor more than one substance at a time, this technique is an important tool for bioprocess monitoring. HPLC coupled to expensive MS does not represent standard equipment at fermentation laboratories. Even if mass spectrometers are available, DAD is often sufficient for quantification because product concentrations are relatively high, so the MS could be used for other issues. In paper II the goal was to develop and validate a method for analytical quantification of both the product and the substrate to enable the proper characterization of the kinetics of the process i.e., the determination of the values of substrate conversion and product formation. 

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Depending upon the experimental design, the purpose of the experiment, and the nature of the mRNA template used to program the translational systems, different types of product quantification should (or could) be used. Aside from the quantification of the luciferase synthesized, which is carried... 

Arnold, S.M., Hickey. W.J.. and Harris. R.F. Degradation of atrazine by Fenton s reagent condition optimization and product quantification. Environ. Sci. Technol, 29(8) 2083-2089,1995. 

Chevrier, D., Rasmussen, S. R., and Gues-Jon, J. L. (1993). PCR product quantification by non radioactive hybridization procedures using an oligonucleotide covalently bount to microwells. Mol. Cell. Probes 7,187-197. 

Winson MK, Todd M, Rudd BAM, Jones A, Alsberg BK, Woodward AM, Goodacre R, Rowland JJ, Kell DB (1998) A DRASTIC (Diffuse Reflectance Absorbance Spectroscopy Taking in Chemometrics) approach for the rapid analysis of microbial fermentation products quantification of aristeromycin and neplanocin A in Streptomyces citricolor broths. In Kieslich, K (ed) New Frontiers in Screening for Microbial Biocatalysts. Elsevier Science B.V., The Netherlands, p 185... 

The possible methods of product quantification include the consumption method, the morbidity method, and the adjusted or extrapolated consumption method. 

In case of system expansion, other than in allocation, benefits attributed by usable secondary products or materials are calculated, which represent the saved environmental impact in another life cycle of the product. Quantification of these benefits depends primarily on the quality of the secondary product and the definition of its application. 

A DRASTIC (Diffuse Reflectance Absorbance Spectroscopy Taking In Chemometrics) Approach for the Rapid Analysis of Microbial Fermentation Products Quantification of Aristeromycin and Neplanocin A in Streptomyces citricolor Broths. 

The timely acquisition of static and dynamic reservoir data is critical for the optimisation of development options and production operations. Reservoir data enables the description and quantification of fluid and rock properties. The amount and accuracy of the data available will determine the range of uncertainty associated with estimates made by the subsurface engineer. 

The plaque assay is desirable because it is very sensitive and only detects infectious viral particles. However, there are viral agents which cannot be supported by cell lines. In these cases other methods must be used. The polymerase chain reaction (PGR), which amplifies DNA or RNA from viral agents, can be used to detect the presence and quantity of viral agents. The amount of RNA or DNA target in the initial sample can be determined by competitive PGR where the quantity of amplified product is compared to a control PGR product where the initial amount of target is known. Quantification is also possible by an end-point dilution method similar to that used to determine a tissue culture infections dose. PGR methods can be very sensitive however. 

In vitro absorption-spectrophotometry techniques are available to assess a sunscreen s efficacy, but the preferred methods are in vivo procedures in which a small body site is irradiated with the desired wavelengths for different periods in the presence or absence of a uv protectant. Procedures vary from country to country to determine the incremental timing of the exposure that ultimately allows quantification via sun protective factor (SPE). In the United States, sunscreen preparations are considered OTC dmg products, and the SPE must be specified (54). Even in countries that do not identify these products as dmgs, SPE labeling has become customary. 

There are at least 3000 different intermediates in current manufacture (over half that number are specifically mentioned in the Colourlndex) and in addition there is a comparatively small number of products manufactured by individual companies for thein own specialties. Only a selection of intermediates can be discussed here, but since 300 of the products probably account for 90% of the quantity of intermediates used, most of the important aspects can be covered. No meaningfiil quantification of wodd tonnage requirements of primaries and intermediates for dyes can be made. 

Relative photoionization cross sections for molecules do not vary gready between each other in this wavelength region, and therefore the peak intensities in the raw data approximately correspond to the relative abundances of the molecular species. Improvement in quantification for both photoionizadon methods is straightforward with calibration. Sampling the majority neutral channel means much less stringent requirements for calibrants than that for direct ion production from surfaces by energetic particles this is especially important for the analysis of surfaces, interfaces, and unknown bulk materials. 

Exposures to chemicals may involve solids, liquids, or airborne matter as mists, aerosols, dusts, fumes (i.e. pm-sized particulates), vapours or gases in any combination. Many situations, e.g. exposure to welding fumes or to combustion products from fossil fuels, include mixtures both of chemicals and of physical forms. Quantification of exposure is then difficult. 

The purpose of this chapter is to show that improvements in safety, quality, and productivity are possible by applying some of the ideas and techniques described in this book. The fact that error reduction approaches have not yet been widely adopted in the CPI, together with questions of confidentiality, has meant that it has not been possible to provide examples of all the techniques described in the book. However, the examples provided in this chapter illustrate some of the most generally useful qualitative techniques. Case studies of quantitative techniques are provided separately in the quantification section (Chapter 5). The first two case studies illustrate the use of incident analysis techniques (Chapter 6). 

The Chemical Process Industry (CPI) uses various quantitative and qualitative techniques to assess the reliability and risk of process equipment, process systems, and chemical manufacturing operations. These techniques identify the interactions of equipment, systems, and persons that have potentially undesirable consequences. In the case of reliability analyses, the undesirable consequences (e.g., plant shutdown, excessive downtime, or production of off-specification product) are those incidents which reduce system profitability through loss of production and increased maintenance costs. In the case of risk analyses, the primary concerns are human injuries, environmental impacts, and system damage caused by occurrence of fires, explosions, toxic material releases, and related hazards. Quantification of risk in terms of the severity of the consequences and the likelihood of occurrence provides the manager of the system with an important decisionmaking tool. By using the results of a quantitative risk analysis, we are better able to answer such questions as, Which of several candidate systems poses the least risk Are risk reduction modifications necessary and What modifications would be most effective in reducing risk ... 

The quantification of kinins in human tissues or body fluids has been limited due to the inherent difficulties in accurately measuring the concentration of ephemeral peptides. Today HPLC-based and RIA/capture-ELA measurements are established to determine kinins in human plasma, liquor or mine. Serine protease inhibitors need to be added to prevent rapid degradation of the kinins in vitro during sample preparation. Kinins and their degradation products have been studied in various biological milieus such as plasma/ serum, urine, joint fluids, kidney, lung and skeletal muscle [2]. Under normal conditions, the concentration of kinins in these compartments is extremely low for... 

The application of RPR in the detection and quantification of species formed by spin-trapping the products of radical-monomer reactions is described in Section 3.5.2.1, The application of time-resolved F.PR spectroscopy to study intermolecular radical-alkene reactions in solution is mentioned in Section 3.5.1. 

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