PLANT CULTURE PLANT CULTURE BIOREACTORS BIOREACTORS Group Lysine Group Lysine Noraini Abd. Rahman Noraini Abd. Rahman Fan Chao Way Fan Chao Way Nurirdayu Jantan Nurirdayu Jantan Nur Suhaili Mohd Yatim Nur Suhaili Mohd Yatim
Jan 14, 2016
PLANT CULTURE PLANT CULTURE BIOREACTORSBIOREACTORS
PLANT CULTURE PLANT CULTURE BIOREACTORSBIOREACTORS
Group LysineGroup Lysine
Noraini Abd. RahmanNoraini Abd. Rahman
Fan Chao WayFan Chao Way
Nurirdayu JantanNurirdayu Jantan
Nur Suhaili Mohd YatimNur Suhaili Mohd Yatim
Characteristic of Plant Cell
Suspension
Characteristic Plant Cell Suspension
Size 10-200 micrometer
Individual Size Aggregates up to 2mm generally form
Growth Rate Slow, doubling time
2-5 day
Inoculation Density High, 10%
Shear Stress Sensitivity
Sensitive and tolerant
Aeration requirement Low
• Plant cell are often found in groups which can alter in size during the cell growth
• The large size, rigid cellulose based cell wall, and large vacuole make the plant sensitive to shear stress.
• Many of method of determining viability in plant cell suspension depend upon the membrane integrity measured by using dyes such as fluorescein diacetate.
• One best method is of measuring viability was determine weather growth can occur after stressing.
• Plant cell suspension have very low growth rate, with doubling of 2-6 days.
• Plant cell have a critical inoculation density below which growth will not occur.
• Along the slow growth rate, it have a low oxygen requirement. (0.1-10mM)
PLANT CELL PLANT CELL BIOREACTOR BIOREACTOR
REQUIREMENTSREQUIREMENTS
PLANT CELL PLANT CELL BIOREACTOR BIOREACTOR
REQUIREMENTSREQUIREMENTS
Table 11.4
Inoculation levels• High inoculation levels required will
not affect bioreactor.• Mean that the inoculation vessels will
be large and scale-up small.• Owing to shear sensitivity and
aggregated nature of the cell suspension, the connections between vessels will have to be large and transfer by gravity or air pressure.
Growth rate• Low growth rate increase productivity
high biomass levels.• At high cell densities the culture will be
viscous and difficult to mix in airlift bioreactor.
• However, for its particular nature, viscosity of plant cell is low, and mixing in airlift BRs is not greatly affected by biomass up to 40gl-1
• Formation of dead zones where conditions are anoxic and cells settle out is a problem.
Temperature• Plant cell suspensions grow
normally at 250C
• With the slow growth rate, heat input and cooling requirements are minimal.
Impeller• In microbial BR, impeller is used:
-to mix the culture-to break up and distribute air bubble to increase oxygen transfer. (main)
• With plant cell cultures, these roles are reversed owing to low O2 requirements and high settling rates.
• Mixing achieved under the restraint of shear sensitivity pf plant cells.
Impeller of Plant Cell BR
• Initially, low impeller speed(50-100rpm) is used.
• For Panax ginseng in a 30L BR, angled disk gave the best result compared to disk Rushton turbine and anchor impeller (Furuya et al.)
• Coleus culture-turbine spiral most effective compared to anchor impellers (Ulbrich et al.)
• Inclined impeller more effective than normal Rushton turbine because it produces less shear while still mixing well.
Type of impeller
Rushton turbine
Anchor Impeller Spiral Impeller
Anchor and spiral impeller
• Cell –lift impeller proved to be better at maintaining viability than flat-bladed impeller (Treat et al.)
• Large flat-bladed impellers showed considerable improvement than small one. (Hooker et al.)
• For shear tolerance, low shear impellers used at low impeller speed appear to be overcomplicated as simple inclined impeller run at 300 rpm or above give adequate mixing at low enough shear.
Cell-lift impellers
Spin Filter with impeller
Cell-Lift impeller
Draft-Tube Basket Impeller
Pitched Blade Impeller
Marine Blade Impeller
• Spin Filter with impeller for suspension or anchorage-dependent cells in perfusion.
• Patented double-screen Cell-Lift impeller for low shear and high oxygenation maximizes yields in microcarrier cultures. If foam accumulates it coalesces in the screened-in foam-inhibitor chamber at top of impeller and dissipates when forced through the screen's pores.
• Patented low shear Draft-Tube Basket Impeller (basket not shown) increases OTR in fibrous-bed cultures.
• Pitched Blade Impeller for high aeration and low shear in insect and other cell cultures.
• Marine Blade Impeller for the growth of insect cells and other cultures
• Due to shear sensitive of the plant cell culture, it is not suitable to use the impellers.
• Another method that suitable for mixing of plant culture is by using the airlift method.
SIMPLE DESIGN FOR PLANT
BIOREACTOR
In the early cultivation of plant cells, In the early cultivation of plant cells, stirred bioreactors were used with stirred bioreactors were used with
the impellers run at low speed.the impellers run at low speed.At 1970s, low shear airlift bioreactor At 1970s, low shear airlift bioreactor
develop.develop.This was adopted as the bioreactor This was adopted as the bioreactor
of choice.of choice.
However, the use of high gassing rates to achieve good mixing can have problems:
Plant cell suspensions sensitive to the level of carbon dioxide.
Other essential volatiles such as ethylene can be stripped off with high aeration rates.
Alternative designs to the airlift and stirred tank bioreactor have been used in the cultivation of plant cells where mixing or aeration is achieved at low shear rates.
A bioreactor based on 2 concentric rotating cylinders as been used to grow Beta vulguris cells.
Aeration is provided by inner cylinder
which was gas permeable. Mixing by vortices produced by
Taylor-Couette Flow.
Mixing Using Taylor-Couette Flow
Another bioreactor is designed to provide bubble-free aeration via rotating coil of gas permeable membranes.
Rotating drum Bioreactor
• Both roots and shoots can be
grown in liquid culture , and such organized structures may be required to stimulate the accumulation of certain secondary product.
• These more organized and larger structures more sensitive to shear stress.
• Alteration in bioreactor design is required.
Plant Bioreactor Plant Bioreactor DesignDesign
Plant Bioreactor Plant Bioreactor DesignDesign
Bioreactor for the cultivation of Bioreactor for the cultivation of plant organ culturesplant organ cultures
• Suspension cultures can be induced to undergo embryogenesis to form small plants.
• Application of this technique at large scale led to the consideration of production of artificial seeds.
• Alternative design, Spin Filter Bioreactor has been successfully used for carrot embryogenesis where;
Rotating filter mixed the culture while allowing medium to be added or removed from culture.
Spin Filter Bioreactor
Bubble Column
• Cylindrical shape• Axial flow (Eddies)• Vertical baffle• Gas is sparged at the base• Movement of the liquid is caused
by the density differences
Internal device: horizontal perforate
plate
Bubble Column
Schematic Diagram:Bubble column
Airlift Bioreactor
• 2 internal zones-riser -downcomerBUT only 1 zone is sparged with air
a)Draft-tube internal loop configurationb)Split cylinder devicec)External loop system
Airlift Bioreactor
*THANKS 4 UR ATTENTION