Key Facts about Plant Cells
and Algae
Plant cells and microalgae are two of the most exciting platforms in modern biotechnology. Plant cell culture enables the sustainable, scalable production of complex secondary metabolites — compounds such as paclitaxel (Taxol®), shikonin, and ginsenoside that are difficult or impossible to produce by chemical synthesis. Beyond pharmaceuticals, plant cell culture is gaining traction in the food and flavour industry: cocoa and coffee cell cultures offer a path to producing aroma compounds and functional ingredients without depending on agricultural supply chains. Microalgae convert CO₂ and light directly into biomass, making algae cultivation in photobioreactors a compelling route to nutraceuticals, pigments, and biofuels.
Both organism groups share key characteristics that define how they need to be cultivated. Plant cells are large (20–200 µm) and enclosed by a rigid cellulose wall, making them significantly more sensitive to shear stress than microbial or mammalian cells. They grow slowly — batch durations of one to four weeks are typical — and their biosynthetic output depends directly on tight control of pH, dissolved oxygen, temperature, and nutrient supply. Microalgae add light as a critical parameter: photosynthetic growth requires defined irradiance and CO₂ supply, and photoinhibition must be actively avoided. Both groups can also be cultivated heterotrophically or mixotrophically, expanding the range of bioreactor strategies available.
These biological properties — shear sensitivity, slow growth, and the need for aseptic, precisely controlled conditions over extended cultivation periods — make bioreactor design critical. They drive the need for gentle mixing, accurate pH and DO control, defined temperature management, and for algae, integrated light supply. The Applikon autoclavable glass bioreactor are ideally suited for plant cell and algae bioreactor applications at small and lab scale, with a clear path to scale-up.
Key Parameters for Plant Cell and Algae Cultivations
Plant cells and microalgae demand precise, organism-specific control across all bioreactor formats — from MiniBio screening to stainless steel production systems.
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pH
Plant cells (5.5–6.0) / Microalgae (7.0–8.5)
In-line pH control via acid/base addition for plant cells; automated CO₂ injection on pH demand for algae cultivation in bioreactors. Deviations directly affect growth rates and secondary metabolite accumulation.
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Dissolved oxygen (DO)
Plant cells (10–40%) / Microalgae
DO cascade control (agitation + aeration) is essential for plant cell culture. In algae photobioreactor cultivation, photosynthetically generated O₂ must be actively stripped to prevent inhibitory accumulation.
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Temperature
Plant cells (20–28°C) / Microalgae (20–35°C)
Species-specific optimum; Chlorella ~25°C, Spirulina cultivation ~35°C. Temperature reduction in plant cell culture can enhance accumulation of target secondary metabolites.
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Light intensity
Microalgae (photobioreactor parameter)
PAR 50–500 µmol m⁻² s⁻¹ depending on species. Light/dark cycles maximise photosynthetic efficiency. The transparent borosilicate glass of the Applikon autoclavable bioreactor supports external LED panel illumination for effective lab-scale photobioreactor operation.
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Shear stress
Both plant cells and algae are highly shear-sensitive. Marine or pitched-blade impellers at low tip speeds (0.1–0.3 m/s) and microspargers are standard to ensure adequate mass transfer without cell damage.
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Conductivity
A key indicator of medium composition and osmotic balance. Monitoring conductivity enables early detection of nutrient depletion or salt accumulation — both of which directly impact cell viability and product yield in plant cell and algae cultures. In-line conductivity sensors support real-time process control without sampling.
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Nutrient supply
Plant cells require medium with sucrose, hormones, and elicitors to trigger secondary metabolite biosynthesis. Microalgae grow on inorganic salts (N, P, trace metals) with CO₂; nitrogen depletion shifts metabolism toward lipids, astaxanthin, or phycocyanin.
Standard Process Workflow for Plant Cell and Algae Cultivations
Both processes follow inoculation, growth/production, and harvest phases, adaptable to batch, fed-batch, or continuous mode.
Plant cell suspension culture
Four-stage process from explant selection to harvest, with elicitation as a critical productivity lever.
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Callus initiation & cell line selection
Explant on MS/B5 medium; high-producing lines selected by metabolite screening.
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Aseptic inoculation
Transfer to plant cell bioreactor at defined density; pH/DO/temperature cascade activated.
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Growth & elicitation phase
Fed-batch nutrient supply; elicitor addition triggers secondary metabolite biosynthesis; packed cell volume (PCV) monitored. A key process challenge is the formation of cell aggregates: as plant cells clump together, mass transfer of oxygen and nutrients to the cell interior becomes limited, reducing productivity and complicating downstream processing. Aggregate size must be actively managed through impeller selection, agitation rate, and medium composition.
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Harvest
Batch or semicontinuous; product extracted from biomass or recovered from medium.
Microalgae photobioreactor cultivation
Three-stage process leveraging axenic pre-culture, cascade control, and selective biomass recovery.
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Inoculation
Axenic pre-culture to target OD; CO₂ sparging and illumination activated at transfer.
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Biomass growth & nutrient strategy
Cascade control of DO/CO₂/pH/light; nitrogen depletion to boost lipids, astaxanthin, or phycocyanin.
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Harvest
Batch or turbidostat mode; biomass recovered by centrifugation, filtration, or flocculation.
Bioreactor Types for Plant Cell and Algae Applications
All Applikon formats support plant cell and algae cultivation with tailored control strategies.
| Type | Scale | Key Use Cases | Plant Cell & Algae-Specific Features |
|---|---|---|---|
| Applikon MiniBio glass mini bioreactor | 0.25–1 L | Media & elicitor screening, strain selection, scale-down model | Low volume reduces cost of plant hormones/elicitors; shear-optimised marine impeller; parallel operation; in-line pH/DO sensors |
| Applikon glass autoclavable bioreactors for plant cell and algae cultivation | 2–20 L | Plant cell suspension culture, secondary metabolite production, photobioreactor setup with external LED illumination, scale-up/scale-down model | Transparent borosilicate glass enables external LED illumination — ideal as lab-scale photobioreactor for Chlorella, Spirulina, or Haematococcus cultivation; flexible pH/DO/temperature/light cascades; autoclavable; multiple sensor ports |
| AppliFlex ST single-use bioreactor for plant cell culture | 0.5–15 L | Recombinant plant proteins, biopharmaceuticals from plant cell culture, rapid process changeover | Disposable vessels eliminate cross-contamination risk for valuable plant cell lines; pre-sterilised reactors; no autoclave cleaning validation required; standard pH/DO/Conductivity sensors |
| Stainless steel bioreactors for large-scale plant cell and algae production | From 20 L to >10,000 L | Industrial plant cell cultivation, large-scale microalgae biomass and biofuel production, CIP/SIP continuous processes | Scalable to 5,000 L and beyond; CIP/SIP for long, sterile cultivation runs; robust pH/DO/Conductivity/Temperature cascade control |
Cultivating Plant Cells and
Algae with Applikon Bioreactors
By integrating these sophisticated features, the Applikon autoclavable glass bioreactor not only optimizes the growth conditions for plant cell and algae applications but also enhances the overall efficiency and yield of the cultivation process — making it an efficient tool for both research and commercial applications in biotechnology.
Detailed Process Guide for Plant Cell and Algae Culture
A structured approach to plant cell and algae bioprocessing ensures reproducibility and consistent yield — from initial inoculation through to commercial-scale production.
The Applikon glass bioreactor provides a meticulously controlled environment essential for cultivating plant cells and algae. Precise regulation of temperature, pH, and gas exchange drives photosynthesis and cellular metabolism — optimizing growth conditions and enhancing the overall efficiency and yield of the cultivation process.
Initiating cultures involves aseptic inoculation with either plant cell suspensions or algal strains. Plant cells, typically introduced as callus or undifferentiated cells, thrive under the bioreactor’s controlled conditions. Algal cultures, introduced from pure strains, benefit from an environment that prevents contamination and promotes robust monocultural growth.
A balanced delivery of nutrients is critical for the cultivation of plant cells and algae. The Applikon glass bioreactor features sophisticated feeding systems that administer a precise mixture of nutrients — including carbon sources (primarily CO₂ for algae), nitrogen, vitamins, and minerals. This targeted nutrient supply is crucial for maintaining optimal growth rates and metabolic efficiency.
Proper gas exchange is vital for supplying CO₂ for photosynthesis while maintaining suitable oxygen levels to support aerobic respiration and prevent oxidative stress. The Applikon autoclavable glass bioreactor is designed to allow efficient gas exchange and aeration, with capabilities for fine-tuning these parameters to meet the dynamic needs of the cultures.
