Establishment of Cell Suspension Cultures

This flashcard set covers the terminology and conceptual growth phases associated with the establishment and maintenance of plant cell suspension cultures.

Cell Suspension Culture

The growth of single or small groups of plant cells in a liquid growth medium, typically initiated from friable callus.

Friable Callus

A type of callus without obvious organ regeneration that easily disaggregates and disperses into single cells or small clumps when transferred to agitated liquid media.

Agitation

The low-speed shaking of liquid cultures used to promote aeration and chemical exchange with the medium.

Compact Callus

A type of callus characterized by dense tissue without any obvious organ regeneration.

Organogenic Callus

Calli with some degree of organ regeneration, categorized as rooty, shooty, or embryonic depending on the organs they form.

Starch Granules

One of the four key characteristics of plant cell lines, along with cell separation, homogeneous morphology, and dense cytoplasm.

Rauvolfia serpentina

A plant species used in cell suspension culture to produce bioactive chemicals for hypertension treatment.

Clinacanthus nutans

Also known as Sabah Snake Grass; it is cultured in suspension for the production of flavonoids and phenolics.

Nutrient Medium Requirements

For successful friable callus proliferation in suspension, the medium should be liquid (without agar) and contain a high auxin concentration relative to cytokinin.

Inoculum Density

The lowest density of cells per volume of medium at which a cell culture will successfully initiate growth.

Medium Conditioning

The process occurring during the lag phase where cells release metabolites (glucose, amino acids, growth factors) into the medium until they reach levels sufficient for cell cycle initiation.

Batch Culture

A system where the medium volume is finite and not replenished, causing growth to continue only until a nutrient (usually carbon) becomes limiting.

Continuous Culture

A system where the medium is replenished during culture to sustain growth; it can be open (grown for years) or closed (terminated at harvest).

Lag Phase

The initial growth phase where cells activate metabolism and medium conditioning occurs prior to cell division.

Exponential Phase

Also known as the log phase, this stage is characterized by exponential cell mass gain due primarily to cell division.

Linear Phase

A phase characterized by linear mass gain due primarily to cell expansion.

Progressive Deceleration

The stage where cell growth slows down and the accumulation of secondary metabolites occurs.

Stationary Phase

The final stage of the growth cycle (generally 12 to 25 days) where growth declines.

Methylation

The addition of a $(CH_3)$ group to DNA which compresses it, leading to the prevention of gene expression.

MS medium supplements for C. nutans

The specific combination of $0.25\,mg/L$ 2,4-D and $0.25\,mg/L$ BAP used to form and proliferate friable callus in leaf explants.