Materials

8 soil samples
8 clean, dry petri dishes
90 plates of Starch-Casein Agar
1 MacConkey’s Plate
1 TSA plate
Glass slides
At least 4 clean, sterile dilution tubes
100ml sterile saline
H202
Motility Slates for each organism
E. coli
Oxidase reagent
Gram’s Iodine
Crystal Violet
Safranin
Alcohol
Distilled water
Malachite Green
 

Procedure

1. Obtain approximately 8 soil samples from different locations.
2. Dry heat each sample in a petri dish for 2 hours at 55?C.
3. Measure out .5g of each sample and place it in a test tube containing 5mL of sterile saline solution.  Then take .5 mL of the solution and transfer it to a second test tube containing 4.5 mL of saline.  Repeat this procedure twice more to perform the dilution a total of 3 times.
4. Plate .5 mL of each dilution on two separate Starch-Casein agar plates and label accordingly.  Also sprinkle a small amount of the dry heated dirt on two separate plates.
5. Incubate one of each type of plate at 25?C and 30?C for 5-7 days in the dark.
6. Look at the plates to identify possible Streptomyces colonies and restreak each on a new Starch-Casein plate.  Continue to restreak until a pure colony is obtained.
7. Perform the following tests on the pure colonies to identify the organism:

            a.) Gram stain
            b.) MacConkey’s Plate
            c.) Catalase test
            d.) Motility stab
            e.) Endospore stain
            f.) Antibiotic test
            g.) Smell
            h.) Oxidase