Concept of Culturing

Welcome to class!

In today’s class, we will be talking about 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 predetermined culture medium under controlled laboratory conditions. Culturing is a technique of growing micro-organisms in the laboratory to study the microbes.

Culturing involves the following activities:

Preparing a sterile medium
Inoculating
Incubating
Examining micro-organism 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, viruses are cultured in the laboratory by injecting the virus into the fertilized bird’s egg e.g. egg of duck.

Purpose of culturing

To isolate a bacteria
To identify and study the properties of bacteria.
To test antibiotic sensitivity.
To create antigen for laboratory use.
Culturing bacteria invitro for genetic studies.

Preparation of Culture Solution

The culture solution called Agar is prepared under sterile conditions.
It is then boiled and poured it into sterile petri-dish
It is allowed to cool and set in the petri-dish
A heat sterilizer may be used to kill micro-organisms 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 set up is Observed and
What is seen for 2-3days is recorded what you

On the culture medium, micro-organisms occur as colonies. Colonies of micro-organism do clump together in a large number 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 disease prevention.

In our next class, we will be talking about Micro-Organism in Action. We hope you enjoyed the class.

Should you have any further question, feel free to ask in the comment section below and trust us to respond as soon as possible.