Culture parameters

Roper, W Schulz, M., Chaouiche, E. and Meloh, K. A. 1985. Nicotine production by tissue cultures of tobacco as influenced by various culture parameters. Journal of Plant Physiology, 118 463 70. 

Kosourov S, Tsygankov A, Seibert M, Ghirardi ML (2002) Sustained hydrogen photoproduction by Chlamydomonas reinhardtii. effects of culture parameters. Biotechnol Bioeng 78 731-740... 

Physiological optimization of enzyme synthesis by variation of the culture parameters is usually required to enhance the catalytic activity of whole-cell biocatalysts to such a level that it can be apphed in a biocatalytic process. In addition, physiological conditions can influence the selectivity of the reaction, since enzymes with opposite selectivities can be differentially expressed. In some cases, genetic engineering is required to obtain biocatalysts with a desired selectivity that does not consume the product of choice (see 5.3.5). Alternatively, one may choose to isolate the desired activity from the culture in order to use the biocatalyst in an enzyme reactor. 

Though especially the cultural parameters of the studied cells have a huge impact on their signature variability it seems that - a decent Raman signature library provided - the majority of cultivation differences can be accommodated and thus no extreme standardization of culturing conditions is required for identification via this method. But for the sake of taxonomic resolution care has to be taken in finding appropriate culturing conditions to affect the implementation possibilities of Raman spectroscopy in microbial analysis positively [43]. 

In 1907, Ross Granville Harrison introduced tissue culture as a new technique for the study of nerve fibre outgrowth [24], At that time, it was hardly envisioned that cell culture would become the most widespread research tool in life sciences and an important method for preparing antibodies, vaccines and drugs. During the development of tissue culture, parameters such as sterility, temperature, gas mixture, medium composition and substrate features were found to be critical for... 

Spheroids are formed through spontaneous aggregation of cells, and their use allows the analysis of the effects of three-dimensional distribution of cells to test compounds, without the disadvantages presented by organ culture. Parameters such as penetration barriers in non-vascular areas and metabolic and proliferation gradients can be studied by use of this model. 

It is important to control culture parameters to insure consistency of glycosylation of a recombinant protein in a culture bioprocess. However, this may not be so easy given that the extent of glycosylation may decrease over time in a batch culture (Curling et al., 1990). This is likely to be due to the continuous depletion of nutrients (particularly glucose or glutamine) and accumulation of metabolic byproducts, which have been shown... 

Viral particle production from cell cultures has several differences from other bioprocesses. The production of molecules like enzymes, toxins, or other proteins synthesized by bacteria, fungi or animals, depend upon culture parameters, such as pH, temperature, dissolved oxygen, or nutrients. Product formation may occur through secondary metabolic pathways, which are not related to the development or growth of the cell. In these situations, research and technological development must be directed to the specific cell and this involves the improvement of the cell as a better molecular production unit. So, there is a direct relation between nutrient conversion, cell growth, and the expected improvement of the final productivity. 

The effectiveness of these control schemes will depend to a great extent on how accurately the various state variables and culture parameters can be estimated on-line and under a variety of operating conditions. Several aspects of the general estimation problem have been studied in situations related to chemical reactors (J, 2). With biochemical reactors, however, the estimation problem is considerably more involved because of the growth... 

Although the yields and total growth rate are useful parameters, it is the state variables like the concentrations of biomass, substrate and product, and the culture parameters like the specific rates of growth, substrate uptake, etc., that provide a complete description of the bioreactor. One attempt in estimating these variables from R and the yields consisted of integrating the governing differential equation with known initial conditions and the measured values for R and the yields (9). For a batch reactor, for example, b was estimated by integrating... 

To implement the above equations in the specific problem of estimating the state of a bioreactor employed for the propagation of a pure culture, the state and measured variables need first be identified. Of the state variables, one would certainly like to monitor the biomass and substrate concentrations, b and s, but also the specific growth rate, u, and yield with respect to the substrate, Y, which are culture parameters. Since it is not desirable to use a model for the dependence of u and Y on b and s, both of them will have to be treated as state variables. The state vector then will comprise four variables, namely, b, s, u and Y. ... 

De Andres, C, Mercade, E., Guinea, J., and Manresa, A. 1994. 7,10-Dihydroxy-8 -octadecenoic acid produced by Pseudomonas sp. 42A2 Evaluation of different cultural parameters of the fermentation. World J. Microbiol. Biotechnol., 10,106-109. 

The optimization of culture parameters and the scale-up of a human hetero-hybridoma in a stirred bioreactor are described in this section. From the viewpoint of scale-up and handling, a stirred bioreactor is chosen as the most practical approach for industrial-scale production of monoclonal antibodies (MAbs). Furthermore, stirred bioreactors are very flexible with regard to the optimization of culture parameters, i.e. oxygen supply (bubble free, air sparging) and culture mode (e.g. batch, fed-batch, chemostat and perfusion). They also give easy access to cell samples at any time of culture, and keep cells homogeneously supplied with nutrients and oxygen. 

The optimization of culture parameters is an important step in scale-up. The growth rate, the viability and the antibody production of hybridoma cells largely depend on culture conditions. Optimization studies were carried out in a 1.5-1 bioreactor, equipped with pH and pO regulators, that provides reproducible culture conditions and minimizes medium requirements. The results were then applied to a 12-1 bioreactor. 

TK Kirk, E Schultz, WJ Connors, LF Loren, JG Zeikus. Influence of cultural parameters lignin metabolism by Phanerochaete chrysosporium. Arch Microbiol 117 227-285,1978. 

Following days Perform culture analysis in CellBag and adjust culture parameters according to above protocol. Perform infection when optimum infection cell density is reached. ... 

These predictions are most easily tested in cultures of microorganisms because of the short generation time and the ease of manipulation of culture parameters. In the light of the present hypothesis it is hardly surprising that many bacteria cultured under optimum growth conditions express no or insignificant amounts of secondary... 

Build a photobioreactor with feedback control to monitor biophysical and biochemical culture parameters. 

Kosourov, S., Tsygankov, A., Seibert, M, and Ghirardi, M.L. Sustained Hydrogen Photoproduction by Chlamydomonas reinhardtii—Effects of Culture Parameters . Biotechnol. Bioeng. 78 p. 731-740 (2002). 

In order to respect the unity of the State and the Nation of Mali, and with the goal of encouraging the policy of development within an area of the national territory which shares very similar geographical, climatic, socioeconomic and cultural parameters, an inter-regional Assembly shall be created between the Regions of the North of Mali, for the benefit of the populations concerned and of the Republic of Mali as a whole. 

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