9/10/18

Rational:

To analyze the soil sample (type of soil, percent water, and pH). This will give metadata that could give further insight into the results that our group finds.

Procedure:

• Cleaned the lab desk with CiDecon and 70% ethanol
• Placed 2 mL of soil in a 15 mL conical vial
• Used aseptic technique to add 10 mL LB broth using a serological pipette
• Started 15 minute timer
• Shook vial for 15 minutes
• Weighed vial at 18.99g then centrifuged at 10,000 G for 5 minutes
• Added 10 mL soil to a falcon tube
• Added DI water up to 30 mL
• Added soil dispersion (3 drops)
• Shook for 30 seconds
• Let sit for 30 seconds
• Poured off supernatent into a conical tube (later poured supernatent back into the falcon tube)
• Weighed empty weigh boat- 2.43 g
• Weighed weigh boat with wet soil- 5.89 g (wet soil- 3.46 g)
• Placed weigh boat  under hood to dehydrate
• Put some soil into a pH vial and filled the rest of the tube with DI water
• Shook the tube for 10 seconds and then let it sit for 2 minutes
• Placed pH paper in the vial for 45 seconds and checked the pH (pH- 6)
• Filtered out centrifuged soil sample with a top filter
• About 7.5 mL was filtered out
• Added Arthrobacter into the tube using the aseptic technique (0.5 g Arthrobacter)
• Then placed tube into the shaking incubator at 3:50 pm 9/10 at 26 degrees Celcius (until 2:30 9/12)
• Cleaned lab desk with CiDecon and ethanol

Fig.2.B – shows the pH of soil sample B to be 6