Fermentation monitoring, biotechnology

Optical biosensors have been applied extensively in many fields, such as the life sciences, for biotechnology quality control, in clinical analysis, environmental control, fermentation monitoring, product control in the food and beverage industry, just to name a few [83 - 96]. They can be used to study a wide variety of biological systems interactions from proteins, oligonucleotides, oligosaccharides, and lipids to small molecules, phage, viral particles and cells [83], determination of bacterial and viral concentrations interactions, between... 

Mass spectrometry (MS) is one sophisticated technique that has been applied relatively recently for monitoring biotechnological processes, but mainly for the on-line detection and quantification of gases [27], MS is described in section 2.10.2. One drawback with MS is that is requires expensive equipment and is not as easy to handle as HPLC coupled to an UV-detector. Diode-array detectors (DAD) have most recently begins to be to be used for monitoring of the fermentation of wines and ethanol [28-30],... 

Figure 22-1. Different sensors used for fermentation monitoring in biotechnology (based on Reference [2]).

Other workers have also demonstrated the potential role of PyMS with ANNs in quantitative biotechnology. Kang et al.106 used the combination to quantify clavulanic-acid production in a Streptomyces clavuligerus fermentation system, while a study by Lee107 indicated that the quantification of clavulanic-acid production by PyMS-ANNs could be used to quantitatively monitor the morphological differentiation process in a Streptomyces fermentation. 

Hosobuchi, M., Kurosawa, K. and Yoshikawa, H. (1993) Application of computer on monitoring and control of fermentation process microbial conversion of ML-236B sodium to pravastatin. Biotechnology and Bioengineering, 42, 815-820. 

It is a method of elemental analysis for various practical reasons and it is essentially suitable for analysis only of metals. A large number of elements can be analyzed for at trace levels. Therefore, its biotechnologic applications mainly involve in measurement of inorganic elements such as alkali, trace, and heavy metals in biological investigations. It is also used in industry to monitor contaminating inorganic elements in bioreactors fermentation process and preparation of culture media. 

In membrane extraction, the treated solution and the extractant/solvent are separated from each other by means of a solid or liquid membrane. The technique is applied primarily in three areas wastewater treatment (e.g., removal of pollutants or recovery of trace components), biotechnology (e.g., removal of products from fermentation broths or separation of enantiomers), and analytical chemistry (e.g., online monitoring of pollutant concentrations in wastewater). Figure 18a shows schematically an industrial hollow fiber-based pertraction unit for water treatment, according to the TNO technology (263). The unit can be integrated with a him evaporator to enable the release of pollutants in pure form (Figure 18b). 

My third example of chemical engineering challenges in biotechnology is a problem in monitoring and control. In virtually all practical fermentations where the medium contains solids and/or where the cell concentrations are greater than 10 g/liter, it is impossible to monitor directly the cell concentration and hence cell activity. It would be most helpful to know the instantaneous cell concentration and activity in order to control the substrate feed rate, particularly in a fed-batch operation. 

The rapid growth of biotechnological research the last decades has emphasized the need for proper analytical techniques for bioprocess monitoring. Rapid identification and quantification of essential components in biotechnological processes is essential for process development and optimization. It has been demonstrated that improved monitoring will result in better control and thus improved productivity [20]. While most bioprocesses still are only monitored by the measurement of traditional parameters, such as CO2, pH and 02, there is an increasing need to also follow the concentrations of fermentation substrates and products [21],... 

Albert S, Kinley RD, Multivariate statistical monitoring of batch processes an industrial case study of fermentation supervision, Trends in Biotechnology, 2001, 19, 53-62. 

In cultivation processes, the chemical environment (normally called the fermentation broth) is one of the main foci in biotechnological analysis [36]. Substrates, products, and several metabolites can usually be found in the fermentation broth. Substrates are consumed by the microorganisms and products or metabolites are released by the cells into the medium. Thus, detailed on-line monitoring of these components can reflect not only the progress of the bioprocess but can also give an insight into the state and metabolism of the microorganisms. 

Matz G, Lennemann F (1996). On-line monitoring of biotechnological processes by gas chromatographic—mass spectrometric analysis of fermentation suspensions. J. Chromatogr. 750 141-149. 

By using optical fibers, biotechnological processes in fermenters can be monitored continuously with spectral measurements. In simple cases, transmission measurements are performed [164] or for monitoring reactions,. scattering phenomena are employed. These techniques are also used in... 

The development of biosensors, especially amperometric enzyme electrodes, is an area where SECM may have an important role. Biosensors find application in the treatment of diabetes mellitus, fermentation control in food processing, and biotechnological production of pharmaceuticals. Such sensing devices consist of a biorecognition layer (e.g., an enzyme layer) and a transducer (e.g., an amperometric electrode). Intensive efforts are currently devoted toward the development of miniaturized biosensors driven by the need to reduce sample volume (e.g., blood drawn from neonates or critically injured patients) or the need to work in confined microenvironments (e.g., in vivo monitoring). 

Peck, M., Chynoweth, D.P., 1992. On-line fluorescence-monitoring of the methanogenic fermentation. Biotechnology and Bioengineering 39, 1151—1160. 

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