Method of Inoculation

Streak Plate Method

The streak plate if properly prepared offers a most practical

way of obtaining discrete colonies and pure culture. But

is of no use if plate is not inoculated properly. The plates

may be prepared in advance in any desired quantity

and stored in the refrigerator until inoculation. The agar

surface should be free of water of condensation before the

streaking is done.

Method I

This method is designed for culture from broth, agar plates

or slopes.

1. Place one loopful of the inoculum near the periphery

of the plate.

2. With a loop spread the inoculum over the upper

portion of the plate.

3. Stab the loop into the agar several times and continue

streaking overlapping the previous streak.

4. Stab the loop as before and continue streaking.

5. Flame the loop allow it to cool and overlap the last

streak and complete streaking.

6. Lift the loop and streak the center of the plate with

zigzag motions.

7. Discrete colonies should be found in the central portion

of the plate while additional importance on hemolytic

activity may be gained from the effect of a reduced

oxygen tension on the organism stabbed into the media.