QUANTIFICATION OF THE EFFECT OF SOME OPERATIONAL VARIABLES ON THE CELL GROWTH YIELD (Yx/s) OF Penilcilium chrysogenum BY SURFACE RESPONSE ANALYSIS

The yield coefficient Yx/s was correlated with variables such as temperature (22.8-29.2 oC), concentrations of corn steep liquor (6.4-57.4 g/L), ammonium sulfate (5.6-18.4 g/L), sucrose (4.0-36.0 g/L) and soybean oil (3.0-7.0 g/L), all important variables in the growth stage of the Penicillium chrysogenum fungus. An empirical model was obtained by response surface statistical experimental design. The tests were performed with a complex culture medium in a rotatory shaker. The highest Yx/s values were obtained at low sucrose concentrations (~4.0 g/L) and high corn steep liquor concentrations (~57.4 g/L). Temperature, ammonium sulfate and soybean oil concentrations showed no significant effect on Yx/

Nomenclature And Guideline To Express The Amount Of A Membrane Protein Synthesized In Animal Cells In View Of Bioprocess Optimization And Production Monitoring

Studies of a bioprocess optimization and monitoring for protein synthesis in animal cells face a challenge on how to express in quantitative terms the system performance. It is possible to have a panel of calculated variables that fits more or less appropriately the intended goal. Each mathematical expression approach translates different quantitative aspects. We can basically separate them into two categories: those used for the evaluation of cell physiology in terms of product synthesis, which can be for bioprocess improvement or optimization, and those used for production unit sizing and for bioprocess operation. With these perspectives and based on our own data of kinetic S2 cells growth and metabolism, as well as on their synthesis of the transmembrane recombinant rabies virus glycoprotein, here indicated as P, we show and discuss the main characteristics of calculated variables and their recommended use. Mainly applied to a bioprocess improvement/optimization and that mainly used for operation definition and to design the production unit, we expect these definitions/recommendations would improve the quality of data produced in this field and lead to more standardized procedures. In turn, it would allow a better and easier comprehension of scientific and technological communications for specialized readers. © 2009 The International Association for Biologicals.381105112Yokomizo, A.Y., Jorge, S.A.C., Astray, R.M., Fernandes, I., Ribeiro, O.G., Horton, D.S.P.Q., Rabies virus glycoprotein expression in Drosophila S2 cells. I. Functional recombinant protein in stable co-transfected cell line (2007) Biotechnol J, 2, pp. 102-109Astray, R.M., Augusto, E.F.P., Yokomizo, A.Y., Pereira, C.A., Analytical approach for the extraction of recombinant membrane viral glycoprotein from stably transfected Drosophila melanogaster cells (2008) Biotechnol J, 3, pp. 98-103Aiba, S., Humphrey, A.E., Millis, N.F., (1973) Biochemical engineering. 2nd ed., , Academic Press, New YorkBailey, J.E., Ollis, D.F., (1986) Biochemical engineering fundamentals. 2nd ed., , McGraw-Hill, New YorkShuler, M.L., Kargi, F., (2002) Bioprocess engineering basic concepts. 2nd ed., , Prentice-Hall PTR, Upper SaddleAdams, D., Korke, R., Hu, W.S., Application of stoichiometric and kinetic analyses to characterize cell growth and product formation (2007) Animal cell biotechnology: methods and protocols. 2nd ed., pp. 269-284. , Pörtner R. (Ed), Humana Press, TutowaDoyle, A., Griffiths, J.B., (1998) Cell and tissue culture: laboratory procedures in biotechnology, , p. 133-59, Wiley, NYTey, B.T., Al-Rubeai, M., Suppression of apoptosis in perfusion culture of myeloma NS0 cells enhanced cell growth but reduces antibody productivity (2004) Apoptosis, 9, pp. 843-852Wurm, F.M., Production of recombinant protein therapeutics in cultivated mammalian cells (2004) Nat Biotechnol, 22, pp. 1393-1398Ma, Z., Yi, X., Zhang, Y., Enhanced intracellular accumulation of recombinat HbsAg in CHO cells by dimethyl sulfoxide (2008) Process Biochem, 43, pp. 690-695Jorge, S.A.C., Santos, A.S., Spina, A., Pereira, C.A., Expression of the hepatitis B vírus surface antigen in Drosophila S2 cells (2008) Cytotechnol, 57, pp. 51-59Galesi, A.L.L., Aguiar, M.A., Astray, R.M., Augusto, E.F.P., Moraes, A.M., Growth of recombinant Drosophila melanogaster Schneider 2 cells producing rabies virus glycoprotein in bioreactor employing serum-free medium (2008) Cytotechnol, 57, pp. 73-81Pamboukian, M.M., Jorge, S.A.C., Santos, M.G., Yokomizo, A.Y., Pereira, C.A., Tonso, A., Insect cells respiratory activity in bioreactor (2008) Cytotechnol, 57, pp. 37-44Swiech, K., Rossi, N., Astray, R.M., Suazo, C.A., Enhanced production of recombinant rabies virus glycoprotein (rRVGP) by Drosophila melanogaster S2 cells through control of culture conditions (2008) Cytotechnol, 57, pp. 51-59Freshney, R.I., (1994) Culture of animal cells: a manual of basic technique. 3rd ed., , Wiley-Liss,, New YorkAugusto, E.F.P., Barral, M.F., Piccoli, R.A.M., Mathematical models for growth and product synthesis in animal cell culture (2008) Animal cell technology: from biopharmaceuticals to gene therapy, pp. 181-220. , Castilho L.R., Moraes A.M., Augusto E.F.P., and Butler M. (Eds), Taylor & Francis, London. 978041542304