1. Purpose:-
To describe the procedure for the
streak plate inoculation for the isolation of discrete
colonies / pure cultures.
2. Scope:-
This procedure is applicable to
study the morphological & biochemical characteristics of different
microbial cultures.
3. HSE
Statement:-
Gloves And Face
mask should be use during test.
4. Responsibilities:-
i)
Manager Quality Control is responsible
to ensure that procedure & formats are followed entirely as approved.
ii)
Microbiologist is responsible to perform the test.
5. Materials:-
5.1 Agar
medium
5.2
Inoculation wire loops.
5.3
Bunsen burner.
5.4
Sterile Petri plates & beakers.
5.5
70% IPA Solution.
6.
Definitions:-
6.1 Culture:-
Population of microorganisms cultivated in
an artificial growth medium. A pure culture is
grown
from a single cell; a mixed culture consists of two or more microbial species
or strains
growing
together
6.2 Streak plate:-
A Petri dish of solid culture medium with
isolated microbial colonies growing on its
surface, which has been prepared by spreading a microbial mixture over
the agar surface, using an inoculating loop. BPL uses a modification of the
Miles-Misra technique.
6.3 Coccoid:-
Sphere-shaped
6.4 Coccus:-
Spherical bacterial cells
6.5 Inoculate:-
To transfer a
liquid, product or micro-organism from one container or agar medium to
another.
7.Flow Chart:-
8. Description:-
8.1 Principle:-
In nature microbial populations
don’t segregate themselves by species but exist with their mixtures of many
other cell types. In the laboratory these populations can be separated into
pure cultures. These cultures contain only one type of organism and suitable
for the study of their specific morphological and biochemical properties.
The
techniques commonly used for the isolation of discrete colonies / pure cultures
initially require that the number of organisms in the inoculums be reduced. For
this purpose streak plate, spread plate or pour plate techniques are used.
The streak plate method is
a rapid qualitative isolation method. It is essentially a dilution technique
that involves spreading a loopful of culture over the surface of an agar plate.
8.2 Procedure:-
8.2.1 Flame and cool the wire loop.
Place a loopful of culture on the surface of agar in area “A” as shown in annex
– 01 and drag it rapidly several times (3 to 4 times) across the surface of
area “A”.
8.2.2
Reflame and cool the wire loop and turn the Petri dish through 90˚, then touch
the loop to a corner of
the last streak of the culture on area “A” and drag it
several times across the agar in area “B”.
8.2.3
The loop should never enter in area “A” again.
8.2.4
Reflame and cool the loop, again turn the Petri plate 90˚ and then drag the
culture from a corner of area “B” across area “C”, using a wide streaker.
8.2.5
Again don’t let the loop touch previously streaked area.
8.2.6 The flaming of the loop at the
point indicated, is to effect the dilution of the culture so that pure
organisms are streaked in each area resulting in the final desired separation.
8.2.7
Incubate streaked plates at 30 – 35 ˚C for 24 – 48 hours.
8.2.8
See annex – 01 for further details.
8.2.9 Study the isolated microbes under the microscope
for their morphological character and determine their biochemical properties by
staining procedures
ANNEX – 01
Streak Plate Inoculation Procedure
N/A
10. Reference:-
11. Distribution:-
This SOP has to be distributed in below mentioned
Departments:-
|
Sr. NO
|
Distributed to
|
Received
(Current)
|
Returned
(Obsolete)
|
|
1
|
Quality Control
Department
|
|
|
|
2
|
Quality Management
Department
|
|
|
12.
Revision History:-
Date Changes
N/A