Principle
- Ashby’s glucose agar is described by Subba Rao (1977) for the isolation of a non-symbiotic nitrogen-fixing bacteria, Azotobacter.
- Ashby’s media is composed of glucose, dipotassium phosphate, magnesium sulfate, sodium chloride, potassium sulfate, and calcium carbonate.
- Glucose provides a carbon source and atmospheric nitrogen serves nitrogen source. Dipotassium Phosphate is a buffering agent.
- The other salts provide various essential ions required for promoting the growth of Azotobacter.
- The presences of calcium carbonate stimulate growth and increase the availability of phosphorus, sulfur, and magnesium to the organisms.
Use:
Recommended for isolation of Glucose fermenting Azotobacter from soil samples.
|
PARAMETERS
|
STANDARD VALUES
|
|
PHYSICAL PARAMETERS:
|
|
Dehydrated Powder
|
Description
|
A fine, free-flowing, hygroscopic powder.
|
|
Color
|
Off-white colored powder.
|
|
Solution
|
Solubility
|
Soluble in Distilled / de-ionized water at 50˚ C
|
|
Color
|
Milky white colored solution with stealing at the bottom on standing
|
|
pH
|
7.4 ±0.2 at 25 ˚C (40.70 g/ l)
|
|
Agar Plates
|
Solidification
|
40 ˚C
|
|
Color
|
Milky white colored opalescent gel with slight precipitate.
|
