A hybrid bioreactor for high density cultivation of plant cell suspensions

Abstract

A hybrid bioreactor was developed for the production of secondary metabolites from high density cultivation of plant cell suspensions. Some of the advantages of both air-lift and cell-lift by agitation were combined. The addition of a decanting column also made it possible to run a perfusion system for high density culture or to run a two-stage culture efficiently. Cell growth and the production of berberine from Thalictrum rugosum in the hybrid bioreactor are reported in this paper. A cell density up to 31 g/l was obtained by perfusion without any problems in mixing or loss of cell viability and the specific berberine productivity was comparable to that in shake flasks. The maximum berberine concentration was 88 mg/l at 3 weeks of operation and declined thereafter.

A high-rate perfusion bioreactor for plant cells

“…Perfusion rate of 22/day was maintained from day 4 to 6, which had to be decreased at 11.7/day on day 7 and 9.8/day on day 8 because of a change in the cell suspension content as discussed previously. These values are on order magnitude higher than that found in literature (Kim et al, 1991;Su and Arias, 2003;Su et al, 1996). However, in order to reduce risks of cell entrainment a safety margin was establish with The culture was performed at optimal operating conditions (4 D-type columns, inlet cross, agitator downwards pumping, 1 cm between top of agitator and wet end of the columns).…”

“…However, as observed by Klvana et al (2004), these systems are susceptible to filter clogging. Kim et al (1991), Su and Arias (2003) and Su et al (1996) have developed perfusion bioreactors strictly based on cell sedimentation. Su et al (1996) obtained a cell retention efficiency of 100% for a packed cell volume (PCV) of 20% but no cell retention was observed at a PCV of 60%, both at 1.0/day in an airlift bioreactor with a cell settling zone delimited by a baffle plate.…”

Plant Cell-Based Bioprocessing

“…The result of extensive foaming is a crust of foam-entrapped cells adhering to the inside of the bioreactor's vessel (called wall growth phenomenon) as well as clogging of the air exhaust filter, which constitutes a contamination risk. Ceramic or sintering steel porous spargers (Kim et al 1991;Zhong et al 1993) generating fine bubbles with higher k L a values, bubble-free aeration via tubes of silicone (Abdullah et al 2000;Ziv 2000), external aeration (Carvalho and Curtis 1998;Kino-Oka et al 1999), and indirect aeration (spinfilter, eccentric motion stirrer, cell-lift impeller) (Eibl et al 1999;Su 1995;Valluri et al 1991) can be used to overcome the disadvantages of sparger rings to plant cells at high bubble aeration rates. However, with the exception of external aeration and ceramic or sintering steel porous spargers, sparger systems have a limited scale-up potential.…”

“…Prominent examples are the cell-lift impeller and the centrifugal-pump impeller, which function both as a fluid pump and aerator (Kim et al 1991;Roberts and Shuler 1997;Zhong 1996a, 1996b;Zhong et al 1999). For example, a maximum dry cell mass concentration of 26 g dw L were achieved in cultivations of Panax notoginseng cells in a centrifugal impeller bioreactor (Zhong 2001).…”

An Envelope-Shaped Film Culture Vessel for Shikonin Production by Lithospermum erythrorhizon Hairy Root Cultures.

“…Various types of culture vessels have been devised for supporting the growth; for example, conical and flat-bottom round flasks placed on reciprocal or gyratory shakers, bubble-type reactors (Tulecke and Nickell, 1959), stirred-jar fermentors (Byrne and Koch,1962;Koge et al,1992), flat-bladed impeller bioreactors (Hooker et al, 1990), rollerbottle systems (Lamport, 1964;Shibasaki et al, 1992), air-lift column bioreactors (Wagner and Vogelmann 1977;Smart and Fowler 1984), cell-lift impeller bioreactors (Treat et al 1989;Kim et al, 1991) and helical-ribbon impeller systems (Jolicoeur et al, 1992) . In these systems, the cultured cells are incapable of surviving without shaking for sufficient oxygen supply.…”