Determination of shear stress thresholds in toxic dinoflagellates cultured in shaken flasks: Implications in bioprocess engineering |
| |
| Affiliation: | 1. PAR-Lab (Padua Algae Research Laboratory), Dept. of Biology, University of Padova, Via Ugo Bassi 58/B, 35121 Padova, Italy;2. CAPE-Lab (Computer-Aided Process Engineering Laboratory) and PAR-Lab (Padua Algae Research Laboratory), Department of Industrial Engineering, University of Padova, via Marzolo 9, 35131 Padova, Italy;3. Interdepartmental Centre “Giorgio Levi Cases” for Energy Economics and Technology, University of Padova, Via Marzolo 9, 35121 Padova, Italy;1. Dep. Informática y Automática, ETSI Informática, UNED, 28040 Madrid, Spain;2. Faculty of Engineering and the Environment, University of Southampton, Southampton, UK;3. Dep. Informática, University of Almería, ceiA3, CIESOL, 04120 Almería, Spain;4. Dep. Ingeniería Química, University of Almería, ceiA3, CIESOL, 04120 Almería, Spain;1. Institute for Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zurich, 8093 Zurich, Switzerland;2. Merck Serono S.A. – Corsier sur Vevey, Zone Industrielle B, 1809 Fenil-sur-Corsier, Switzerland;3. Department of Chemical Engineering, University of Chemistry and Technology, Technicka 3, 166 28 Prague, Czech Republic;1. Université Clermont Auvergne, CNRS, SIGMA Clermont, Institut Pascal, F-63000 Clermont-Ferrand, France;1. Department of Informatics, Universidad de Almería, ceiA3, CIESOL, E04120 Almería, Spain;2. Department of Chemical Engineering, Universidad de Almería, Spain;3. Institute for Research in Agriculture and Fisheries, Junta de Andalucía, E04720 Almería, Spain |
| |
| Abstract: | Marine dinoflagellates are potentially important innovative sources of high-value toxins in biomedical, toxicological and chemical research programs. However, little is known about the difficulties related to dinoflagellate cultures. In this article, we demonstrate that the shear sensitivity of cells may be one of the main causes. The red-tide Protoceratium reticulatum, a producer of yessotoxins, was used to examine the effect of hydromechanical shear stress associated with intermittent fluid agitation on cell growth. Shaken flasks, widely used in biotechnological process research, were used as model bioreactors, as hydrodynamic shear stress is relatively easy to quantify in them. Intermittent turbulence regime was characterized by three key operating variables: shear stress, cycle time or shaking frequency, and fraction of time shaken per agitation cycle. The light/dark cycle was also used as another variable. Cell damage depended on the combination of the above-mentioned variables. A damage threshold was observed at an average shear stress of approximately 0.16 mN m−2 (equivalent shear rate of 0.12 s−1). Cell damage from exposure to average detrimental shear stress was also shown to be greater in the dark than in the light period. Preliminary experiments demonstrated that dinoflagellates are also much more sensitive to bubbling than the majority of common fragile microalgae. Although slight toxicity of Pluronic F-68 was observed at a concentration of 0.05% (w/v), this protective medium additive considerably reduced cell breakage. On the other hand, no cell adaptation to stronger shear stress was observed. Finally, the implications of the proposed approach for the hypothetical mass culture of dinoflagellates in bioreactors were also thoroughly assessed. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
