In this class, we will discuss the concept of culturing. Enjoy the class!
The Concept of Culturing Microbial culture is a method of multiplying microbial organisms by letting them reproduce in a predetermined culture medium under controlled laboratory conditions. Culturing is a technique of growing microorganisms in the laboratory to study the microbes.
Culturing involves the following activities:
Preparing a sterile medium
Inoculating
Incubating
Examining microorganisms in the medium.
While bacteria, fungi, and algae can be grown in test tubes and Petri dishes in culture media, viruses cannot be grown. They can only grow and multiply inside the living cells of an organism.
To carry out studies involving viruses, the viruses are cultured in the laboratory by injecting the virus into the fertilized bird’s egg, e.g. egg of a duck.
Purpose of culturing
To isolate a bacterium
To identify and study the properties of bacteria.
To test antibiotic sensitivity.
To create an antigen for laboratory use.
Culturing bacteria in vitro for genetic studies.
Preparation of Culture Solution
The culture solution called Agar is prepared under sterile conditions. It is then boiled and poured into a sterile petri-dish. It is allowed to cool and set in the petri dish. A heat sterilizer may be used to kill microorganisms in the petri dish
The material is then introduced into the agar medium and covered immediately
The petri dish is placed in a warm but dark compartment or an incubator
The setup is observed, and what is seen for 2-3days is recorded. What you
On the culture medium, microorganisms occur as colonies. Colonies of microorganisms do clump together in large numbers of an organism of the same kind. Colour, appearance, and other characteristics of the colonies enable the investigator to identify and differentiate microbes in a culture medium.
Bacterial cultures
Colonies of the bacteria known as Escherichia coli (larger, pink) and Proteus Vulgaris (smaller, brown) grow side by side in this petri dish culture. Under normal circumstances, both of these bacteria harmlessly inhabit the human intestines and aid in digestion, but they can become pathogenic and cause infections, such as urinary tract infections. Scientists and doctors grow cultures of bacteria and study their characteristics to learn about bacterial diseases and prevention.
In our next class, we will discuss Micro-Organism in Action.