Microbiology - Experiment 7 - Microbial Preservation Techniques by Nuyul Ismail

Material

nuyulismayil — 2018-11-02 05:49:54 UTC

For this experiment, the material that have used was:-
🚂 sterile 30% glycerol
🚂 bacteria calture
🚂 nutrient agar plate

Part A (Before mid-sem break)

nuyulismayil — 2018-11-02 06:00:14 UTC

🚂1. Aliquot 500 μl of sterile 30% glycerol was put into sterile microcentrifuge tube. 

🚂2. 500 μl of bacterial culture was added to the tube and mixed with the glycerol using a vortex mixer. 

🚂3. The tube was labeled with the organism name, strain, date, etc. 

🚂4. The tube was placed in the freezer (-20 °C) and the location was recorded.

Apparatus

nuyulismayil — 2018-11-02 06:01:43 UTC

🚂 sterile microcentrifuge tube 
🚂 freezer
🚂 sterile pipette tip
🚂 wire loop
🚂 vortex mixer

Part B (After mid-sem break)

nuyulismayil — 2018-11-02 06:03:18 UTC

🚂1. To activate bacteria, only a small volume of culture was needed to be removed from the tube. The tube doesn't need to be thawed.

E. coli colony

nuyulismayil — 2018-11-02 06:03:49 UTC

refering to the picture, the E. coli coloy shape (form) on agar plate is irregular and the margin is undulate. the elevation, siza and texture is flat, moderate and smooth. the appearance, pigmentation and optical property is shiny, nonpigmented (white) and opaque.

nuyulismayil — 2018-11-14 09:48:18 UTC

🚂2. The tube was opened and the frozen culture was scrape with a sterile pipette tip. The tube was placed into the freezer (-20 °C) immediately.

nuyulismayil — 2018-11-14 09:48:37 UTC

🚂3. The small volume of frozen/thawed cells was transfer to an agar plate and streak.

nuyulismayil — 2018-11-14 09:48:49 UTC

🚂4. The viability of the bacterial culture was checked after 2 weeks by inoculating the thawed cells on Nutrient agar plate.

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nuyulismayil — 2018-11-14 09:49:05 UTC

🚂5. After 24 hours of incubation at 37 °C the the viability of the culture was checked.

Bacillus colony

nuyulismayil — 2018-11-16 03:07:12 UTC

refering to the picture, the Bacillus colony shape (form) on agar plate is irregular and the margin is undulate. the elevation, siza and texture is flat, moderate and smooth. the appearance, pigmentation and optical property is shiny, nonpigmented (white) and opaque.