Task:

To determine the colony count of the ETP culture sample of the 3rd Day and 7th day on Sabouraud Dextrose Agar and Nutrient agar.

Objective:

To determine the difference in bacterial growth 3rd day and 7th day in the ETP plant.

Procedure:

A) Preparation of Saboured Dextrose Agar Media of 150 ml (7 Feb 2022):

  1. Took 30 ml distilled water in a Conical flask.
  2. Weighed 9.75 gm Saboured Dextrose Agar and added to the conical flask.
  3. Made up volume upto 150 ml with distilled water.
  4. Preheated to dissolve the media uniformly.
  5. Autoclaved the Media.

B) Preparation of Nutrient Agar Media of 150 ml (7 Feb 2022):

  1. Took 30 ml distilled water in a Conical flask.
  2. Weighed 4.2 gm Nutrient Agar and added to the conical flask.
  3. Made up volume upto 150 ml with distilled water.
  4. Preheated to dissolve the media uniformly.
  5. Autoclaved the Media.
SDA and N.A. Media

C) Plates Pouring (7 Feb 2022):

  1. Autoclave petri plates
  2. Once media (N.A. & SDA) is autoclaved, allow the autoclave to cool down.
  3. Place the autoclaved media in laminar air flow. Switch on UV light for 15 mins.
  4. Once the media cools down at optimum temperature (Not very hot nor very cold), pour media into sterile petri plate (approx. 30 ml in each plate).
  5. Made 6 plates of SDA and 6 plates of NA. Keept plates overnight in laminar for sterility testing.

D) Serile Dilution (8 Feb 2022):

  1. Autoclaved glasswares required for serial dilution ( Spreader, Testtubes, Distilled water, pipette).
  2. Serile dilution done of sample 1 (3rd day sample from ETP plant) and sample 2 ( 7th day sample from ETP plant).
  3. Inoculation done from tubes of 10^-6 to 10^-7 (0.1 ml) onto both SDA and NA plates.
  4. Plates were incubated in incubator at 36 degree Celcius.
Plating on SDA and NA media

Observation (10 Feb 2022):

SDA plates Colony countNA plates colony count
Sample 110 x 10^-63 X 10^-6
Sample 225 x 10^-628 X 10^-6

Conclusion:

The colony count of ETP culture gets increased. This means the culture of the ETP plant is efficiently working.