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.
EMB Agar - An isolation medium for the differentiation of the Enterobacteriaceae.
Typical composition (g/litre):
- Peptones 10.0
- di-Potassium hydrogen phosphate 2.0
- Lactose 5.0
- Sucrose 5.0
- Eosin yellowish 0.4
- Methylene blue 0.07
- Agar-agar 13.5.
Preparation: Suspend 36 g in 1 litre of demin. water by heating in a boiling water bath or in a current of steam; autoclave (15 min. at 121oC).
pH: 7.1 ± 0.2 at 25oC.