DATE: 17/08/2022
EXPERIMENT NO: 1.1.
QUADRANT STREAKING
AIM:
To perform quadrant streak method for isolation of pure cultures.
PRINCIPLE:
The techniques commonly used for isolation by discrete colonies initially require that
the number of organism in the inoculum be reduced. The resulting diminution of the
following inoculation, individual cells will be sufficiently for on apart on the surface of
the agar medium to separate the different species. The following are the techniques that
can be used to accomplish the necessary pure culture isolation. The steel plate is a rapid
qualitative isolation method. It is essentially a dilution that spreading a loopful of
culture over the surface of the agar plate.
The sample or the inoculum is diluted boo streaking it surface of agar plates. While
streaking in successive area of plates, the inoculum is diluted into the point where there
is only one bacterial cells deposited every few millimeters on the surface of the agar
plates. When these lone bacterial cells divide and give rise to thousands and thousands
of new bacterial cells, an isolated colony is formed . Pure cultures can be obtained by
picking well isolated colonies and restreaking these on fresh agar plates.
MATERIALS REQUIRED:
A source of bacterial ( Stock culture, previously streaked agar plate or any
other inoculum )
Inoculation loop
Bunsen burner
Nutrient agar
Petri plates
Conical flask
Distilled water
70% Ethanol
EXPERIMENT NO: 1.1.
QUADRANT STREAKING
AIM:
To perform quadrant streak method for isolation of pure cultures.
PRINCIPLE:
The techniques commonly used for isolation by discrete colonies initially require that
the number of organism in the inoculum be reduced. The resulting diminution of the
following inoculation, individual cells will be sufficiently for on apart on the surface of
the agar medium to separate the different species. The following are the techniques that
can be used to accomplish the necessary pure culture isolation. The steel plate is a rapid
qualitative isolation method. It is essentially a dilution that spreading a loopful of
culture over the surface of the agar plate.
The sample or the inoculum is diluted boo streaking it surface of agar plates. While
streaking in successive area of plates, the inoculum is diluted into the point where there
is only one bacterial cells deposited every few millimeters on the surface of the agar
plates. When these lone bacterial cells divide and give rise to thousands and thousands
of new bacterial cells, an isolated colony is formed . Pure cultures can be obtained by
picking well isolated colonies and restreaking these on fresh agar plates.
MATERIALS REQUIRED:
A source of bacterial ( Stock culture, previously streaked agar plate or any
other inoculum )
Inoculation loop
Bunsen burner
Nutrient agar
Petri plates
Conical flask
Distilled water
70% Ethanol
