selecting enrichment culturing conditions, the environment conditions of the sample
collection site must be considered alongside the characteristics of the target alga
(e.g., temperate or light intensity and saline concentration).
While pure (axenic) strains may be obtained through isolation manipulation, the
result is often a unialgal strain coexisting with bacteria.
7.2.3 Examining Culturing Conditions
To ensure an adequate supply of stable research material (blue-green algae or other
microalgae), consideration must be given to the cultural conditions, including light,
temperature, pH, saline concentration, and type or composition of the culturing
solution. Indicators that can be used to compare culturing conditions include
number of cells per volume of culturing solution, weight (wet or dry), packed cell
volume, and biogenic substances such as proteins or chlorophyll, and sequential
rises in the solution’s absorbance. An explanation on how to find the exponential
phase generation time (the time needed for a single division) and specific growth
rate will be provided later. Because specific cell function activity and amounts of
particular components often vary by propagation time, consideration should also be
given to obtaining cells with high levels of activity or content in the biogenic
substance under examination.
7.2.4 Culturing Methods
Culturing methods including batch culture, which involves culturing in a specific
volume of medium and harvesting at a suitable time for the research purposes, and
continuous culture, in which cells are supplied continuously. The latter includes
approaches of semi-continuous culturing, in which part of the culturing solution is
regularly replace in a new medium; the turbidostat approach, which maintains a
fixed cell density; and the Chemostat approach, which adjust the addition of specific
nutrient salts to ensure a constant proliferation rate.
With the typically batch culturing approach, observation of the solution at any
given time during culturing will show cells at various different stages of the cell
cycle (although this state cannot be described as fully irregular). A contrast
approach is synchronous culturing, in which overall cell proliferation in the solution
is made to conform to the same cell cycle. Because this approach supplies cells that
are physiologically and biochemically uniform, it is used for studies of changing
physiological functions within the cell cycle.
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collection site must be considered alongside the characteristics of the target alga
(e.g., temperate or light intensity and saline concentration).
While pure (axenic) strains may be obtained through isolation manipulation, the
result is often a unialgal strain coexisting with bacteria.
7.2.3 Examining Culturing Conditions
To ensure an adequate supply of stable research material (blue-green algae or other
microalgae), consideration must be given to the cultural conditions, including light,
temperature, pH, saline concentration, and type or composition of the culturing
solution. Indicators that can be used to compare culturing conditions include
number of cells per volume of culturing solution, weight (wet or dry), packed cell
volume, and biogenic substances such as proteins or chlorophyll, and sequential
rises in the solution’s absorbance. An explanation on how to find the exponential
phase generation time (the time needed for a single division) and specific growth
rate will be provided later. Because specific cell function activity and amounts of
particular components often vary by propagation time, consideration should also be
given to obtaining cells with high levels of activity or content in the biogenic
substance under examination.
7.2.4 Culturing Methods
Culturing methods including batch culture, which involves culturing in a specific
volume of medium and harvesting at a suitable time for the research purposes, and
continuous culture, in which cells are supplied continuously. The latter includes
approaches of semi-continuous culturing, in which part of the culturing solution is
regularly replace in a new medium; the turbidostat approach, which maintains a
fixed cell density; and the Chemostat approach, which adjust the addition of specific
nutrient salts to ensure a constant proliferation rate.
With the typically batch culturing approach, observation of the solution at any
given time during culturing will show cells at various different stages of the cell
cycle (although this state cannot be described as fully irregular). A contrast
approach is synchronous culturing, in which overall cell proliferation in the solution
is made to conform to the same cell cycle. Because this approach supplies cells that
are physiologically and biochemically uniform, it is used for studies of changing
physiological functions within the cell cycle.
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7 Microalgae, a Biological Resource for the Future