20.2 Cultivation and Processing of Microalgae

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water expulsion from the item is basic in any conversations about enormous scope

fuel creation. The solar drying process may be used for water removal but has a

serious concern of large land requirement for drying which thus makes it unfit for

large-scale processes [8].

20.2.1

Cultivation of Microalgae

It is very important to isolate and cultivate the microalgal species for biofuel produc-

tion. Cells are segregated and grown in appropriate surroundings. The method of

cell culture consists of various steps for a long-lasting period. The culture conditions

should be similar to that of the natural environment. The cultivation of microalgae

is done in the following sequence.

20.2.1.1

Isolation of Cell Cultures

The sample collection is the initial procedure followed by isolation of the required

cell. The growth of these green algae requires simple elements like light, water,

carbon source, temperature, and fewer macronutrients. These conditions are more

prevalent in coastal and oceanic sites and some from rock pools or even shorelines.

These samples are collected from these sites. Samples from these sites are collected

in separate bottles consisting of a cylindrical tube with stoppers at the ends; it may

be fitted with a closing device activated by a messenger. The microalgae samples

that are collected need to be handled gently with care. These have to be transferred

rapidly because the damaged and dry cells cannot produce viable cultures. The

collection details including date, location, date, depth of sample from where they

are collected, water temperature, etc., must be recorded for references. The collected

samples may then be transported in small plastic water bottles. Before the bottle

is filled, it may be rinsed with the sample water to avoid the bubbles. The bottle

containing samples must be well insulated.

20.2.1.2

Single-Cell Isolation

The micropipette is used to isolate the single cell. It is done to remove a particular cell

from the water sample without damage and put the same into a germ-free droplet

of growth medium. The sterile droplet consists of the target cell. Optimum culture

medium for algal growth has to be established as the newly isolated strain will be

difficult for maintenance. The isolates can be put into several culture media and

their growths are monitored. Algal growth is monitored regularly under microscopic

examination. If the culture begins to grow, it has to be relocated to a glass flask or

culture vessel. On establishing the culture, it may be grown in huge volumes. Other

isolation methods are also used by different researchers. They include the use of

agar, centrifugation, flow cytometry, dilution techniques, and photo axis.

20.2.2

Techniques

20.2.2.1

Filtration

Filtration is the most appropriate method for sterilization of the samples of smaller

quantities and heat-sensitive elements like vitamins. Membrane filters may be used