Lab

1
Lab 18 Fall 2009

• Enterotube II
• Soil Microbiology

2
Enterotube II

• Identification of enteric (Gram-negative
  intestinal) bacilli.
• Rapid multi-chambered test
• The twelve small compartments substitute for
  twelve test tubes containing appropriate media
  for these tests glucose, lysine, ornithine,
  H2S/indole, adonitol, lactose, arabinose,
  sorbitol, Voges-Proskauer, Dulcitol/PA, urea and
  citrate.
• The wire inserted in the Enterotube is used to
  obtain growth from an isolated colony of the test
  organism. The wire is pushed down through the
  twelve compartments, inoculates each test as it
  is pulled through the opposite end.

3
E. coliThis organism is positive for
Glucose, Lysine, Lactose, Arabinose, and
Sorbitol. Score all the positives ID number is
24160.
4
ENVIRONMENTAL MICROBIOLOGYSoil Microbial Count

• Teams of 4
• Weigh 1 g of soil on the digital scale
• Do not take the melted agar
• Until the dilutions have been
• Made and plates have been
• Labelled and filled

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ENVIRONMENTAL MICROBIOLOGYSoil Microbial Count

• Teams of 4
• Media
• Make 3 plates nutrient Agar (for bacteria)
• Make 3 plates Sabaroud Agar (for Fungi)
• Make 3 plates Glycerol Yeast Extract Agar (for
  actinomycetes)
• Use Melted Agars (in water bath) pour 1 tube
  into each plate

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1 gram of soil
1 ml
10-2
10-4
Add the soil to a bottle of peptone water - mix
the bottle
0.1 ml
1 ml
1 ml
10-2
10-4
10-5
Add melted Nutrient agar
10-2
10-5
10-4
Add melted Sabaroud agar
10-2
10-4
10-5
Add melted Glycerol Yeast Extract agar
7
1 gram of soil
Transfer 1 ml from the first bottle to the second
- mix the bottle
1 ml
10-2
10-4
0.1 ml
1 ml
1 ml
10-2
10-4
10-5
Add melted Nutrient agar
10-2
10-5
10-4
Add melted Sabaroud agar
10-2
10-4
10-5
Add melted Glycerol Yeast Extract agar
8
Label 9 empty petri plates as per the diagram in
your lab manual
10-2
10-4
0.1 ml
1 ml
1 ml
10-2
10-4
10-5
10-2
10-5
10-4
10-2
10-4
10-5
9
Mix the melted agar and diluted soil together by
gently moving the plate in a figure 8. Allow
the plates to solidify before putting them in the
incubator.
10-2
10-4
10-5
Add melted Nutrient agar
10-2
10-5
10-4
Add melted Sabaroud agar
10-2
10-4
10-5
Add melted Glycerol Yeast Extract agar
10
UN Bacterial Unknowns

• Check your streak plates if you have isolated
  colonies, put them on nutrient slants if not,
  re-streak your unknown
• Media
• 1 2 Nutrient agar slants or 1 Nutrient Agar
  plate