Characterization of fluid-flow resistance in root cultures with a convective flow tubular bioreactor

Edgard B. Carvalho, Wayne R. Curtis

Research output: Contribution to journalArticlepeer-review

47 Scopus citations


Agrobacterium transformed root cultures of Hyoscyamus muticus were grown in a recirculating 2 L tubular bioreactor system. Performance of this convective flow reactor (CFR) was compared to a bubble column (BC) reactor of the same geometry: replicated CFR experiments produced an average tissue concentration of 556 ± 4 grams fresh weight per liter in 30 d whereas the bubble column produced only 328 ± 5 grams per liter corresponding to 25.3 ± 0.0 and 14.3 ± 0.5 grams dry weight per liter, respectively. Because media nutrient levels were maintained sufficiently high to saturate growth rate, the improved performance of the CFR is attributed to enhanced convective mass transfer. The pressure drops observed for flow through roots grown within the reactors were more than an order of magnitude higher than previously obtained by placing roots grown in shake culture into defined geometries. The experimentally observed flow resistance was much higher than would be predicted from correlations using the root diameter as the characteristic diameter for flow resistance. Several lines of evidence suggest that root hairs are a substantial contributor to the observed high flow resistance in these transformed root cultures. Pressure drop increased nonlinearly with velocity which could not be adequately described by a modified form of the Ergun equation. Kyan et al's (1970) equation, although predicting such curvature, relies almost exclusively on an empirical packing deflection term to describe the hydrodynamic behavior. Implications of these results to the design of submerged reactor systems for root culture are discussed.

Original languageEnglish (US)
Pages (from-to)375-384
Number of pages10
JournalBiotechnology and bioengineering
Issue number3
StatePublished - Nov 5 1998

All Science Journal Classification (ASJC) codes

  • Biotechnology
  • Bioengineering
  • Applied Microbiology and Biotechnology


Dive into the research topics of 'Characterization of fluid-flow resistance in root cultures with a convective flow tubular bioreactor'. Together they form a unique fingerprint.

Cite this