Summary
Design equations for oxygen transfer rates were developed to examine the influence of poor mixing in large-scale reactors for root culture. The experimentally observed condition of plug flow of the gas and axially stratified liquid was compared to the typical bioreactor design case of a well mixed gas and liquid phase. In addition, the effect of hydrostatic pressure was included to consider the case for large-scale systems (up to 10,000 L). Calculations were carried out based on typical operating conditions at a root tissue concentration of 200 grams fresh weight per liter. The kinetics for biological oxygen demand were taken as first order, based on experimentally measured rates of root extension at different dissolved oxygen levels. These kinetics are believed to result from diffusion controlled oxygen transport within the root tissue. Unless hydrostatic head effects were considered, the assumptions of mixing did not affect the predicted oxygen availability (dissolved oxygen) to the roots. This results because the low respiration rates, at a typical gassing rate of 0.2 VVM, do not appreciably alter the gas composition as it passes through the reactor. When hydrostatic pressure is considered, the calculations predict increases in volumetric oxygen uptake rate of about 15% from small to larger scale vessels, independent of the mixing assumptions. However, since roots inhibit mixing, a 33% increase in dissolved oxygen is predicted for the bottom of a large scale reactor as a result of increased oxygen transfer rates. In contrast to a well mixed system, where the hydrostatic dependent differences in oxygen transfer are uniformly distributed, the lack of mixing in a reactor of cultured roots will result in substantial differences in oxygen availability from the top to the bottom of the reactor. Refinements needed for the design equations are discussed including the influence of localized meristematic respiration, and the potential for fluorescent imaging to provide more details into tissue oxygen gradients.
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References
Altman, P. L; Dittmer, D. S. Metabolism - Biological Handbooks; Federation of American Societies for Experimental Biology: Bethesda, Maryland, 1968.
Armstrong, W.; Beckett, P.M. Root aeration in unsaturated soil: a multi-shelled mathematical model of oxygen diffusion and distribution with and without sectoral wet-soil blocking of the diffusion path. The New Phytologist 1985, 100, 293–311.
Bordonaro, J. L.; Curtis, W. R. Development of a fluorescent tracer technique to evaluate mixing in plant root culture. Biotechnology Techniques 1997, 11(8), 597–600.
Carvalho, E. B.; Holihan, S.; Pearsall, B.; Curtis, W. R. Effect of root morphology on reactor design and operation for production of chemicals. In: Hairy Roots; Doran, P., Ed.; Gordon and Breach/Harwood Academic UV: Amsterdam, Netherlands, 1997; pp 151–168.
Curtis, W. R. Cultivation of roots in bioreactors. Current Opinion in Biotechnology 1993, 4(2), 205–210
Dilorio, A. A.; Weathers, P. J.; Cheetham, R. D. Non-lethal secondary product release from transformed root cultures of Beta vulgaris. Applied Microbiology and Biotechnology 1993, 39, 174–180.
Doernenburg, H.; Knorr, D. Generation of colors and flavors in plant cell and tissue culture, Critical Reviews in Plant Sciences 1996, 15(2), 141–168.
Gilroy, S. Fluorescent probes of plant cell function. Annual Review of Plant Physiology and Plant Molecular Biology 1997, 48, 165–190.
Kino-Oka, M.; Mine, K.; Taya, M.; Tone, S.; Ichi, T. Production and release of anthraquinone pigments of madder (Rubia tinctorum) under improved culture conditions. Journal of Fermentation and Bioengineering, 1994a, 77, 103–106.
Kino-Oka, M.; Taya, M.; Tone, S. Investigation of oxygen transfer on culture of plant hairy roots in bioreactor. In: Proceedings qf the Third Asia-Pacific Biochemical Engineering Conference, Singapore, June 13–15; Teok W. K., Yap, M. C. S., Oh, S. K. W., Eds.; National University of Singapore: Singapore, 1994b.
Longmuir, I. S.; Knopp, J. A. Measurement of tissue oxygen with a fluorescent probe. Journal of Applied Physiology 1976, 41(4), 598–602.
Machlis L.; The respiratory gradient in barley roots. American Journal of Botany 1944, 31, 281–282.
Mukundan, U. Large scale production of betalains by hairy root cultures of Beta vulgaris. In: Proceedings of the Brainstorming Session in Food Biotechnology, Mysore, India, May 7–8; Prakash, V., Ed.; DBT, CFTRI Press: India, 1993; pp 74–76.
Payne, G. F.; Bringi, V.; Prince, C.; Shuler, M. L. Plant Cell and Tissue Culture in Liquid Systems; Hanser: Munich, 1991; p 256.
Prince, C.; Bringi, V.; Shuler, M. L. Convective mass transfer in large porous biocatalysts: plant organ cultures. Biotechnology Progress 1991, 7, 195–199.
Ramakrishnan, D. Design Principles for Large-Scale Growth of Root Cultures in Bioreactors. Ph.D. Thesis, The Pennsylvania State University, University Park, PA, 1997.
Ramakrishnan, D.; Curtis, W. R. Elevated meristematic respiration in plant root cultures: implications to reactor design. Journal of Chemical Engineering of Japan 1995, 28(4), 491–493.
Ramakrishnan, D.; Salim, J.; Curtis, W. R. Inoculation and tissue distribution in pilot-scale plant root bioreactors. Biotechnology Techniques 1994, 8(9), 639–644.
Sauerwein, M.; Yamazaki, T.; Shimomura, K. Hemandulcin in hairy root cultures of Lippia dulcis. Plant Cell Reports 1991, 9, 579–581.
Reineccius, G. Source Book of Flavors. 2nd ed.; Chapman and Hall: New York, 1994.
Taya, M.; Mine, K.; Kino-Oka; M.; Tone, S.; Ichi, T. Production and release of pigments by culture of transformed hairy root of red beet. Journal of Fermentation and Bioengineering 1992, 73, 31–36.
Tescione, L.; Ramakrishnan, D.; Curtis, W. R. The role of liquid mixing and gas-phase dispersion in a submerged, sparged root reactor. Enzyme & Microbial Technology 1997, 20, 207–213.
Yu, S.; Doran, P. M. Oxygen requirements and mass transfer in hairy root culture. Biotechnology and Bioengineering 1994, 44, 880–887.
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Tescione, L., Asplund, P., Curtis, W.R. (1999). Reactor Design for Root Culture. In: Fu, TJ., Singh, G., Curtis, W.R. (eds) Plant Cell and Tissue Culture for the Production of Food Ingredients. Springer, Boston, MA. https://doi.org/10.1007/978-1-4615-4753-2_13
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DOI: https://doi.org/10.1007/978-1-4615-4753-2_13
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