Agar is a jelly-like substance, obtained from red algae, used heavily as a solid medium for growing various microbes. Many specific formulations are available because some microbes prefer certain environmental conditions over others.
Lactose Broth - A liquid medium for use in the performance or confirmation of the Presumptive Test for coliforms in water, milk, etc. as specified by the American Public Health Association.
Typical composition (g/litre):
- Peptones from gelatin 5.0
- Meat extract 3.0
- Lactose 5.0.
Preparation:
- Suspend 13 g in 1 liter of demin. water
- Dispense into reagent tubes fitted with fermentation tubes
-
Autoclave (15 min. at 121oC).
pH: 6.9 ± 0.2 at 25oC.