Reinforced Clostridial Medium (RCM), 500g

Description

Medium proposed by HIRSCH and GRINSTED (1954) for the cultivation and enumeration of clostridia, other anaerobes
and facultative microorganisms in foodstuffs, clinical specimens and other materials.

Typical Composition (g/litre)
Meat extract 10.0;
peptone 5.0;
yeast extract 3.0;
D(+)glucose 5.0;
starch 1.0;
sodium chloride 5.0;
sodium acetate 3.0;
L-cysteinium chloride 0.5;
agar-agar 0.5

Preparation
Dissolve 33 g/litre, dispense into test tubes, autoclave (15 min at 121 °C). Cool, if required add 0.02 g Polymyxin B/litre in form of an aqueous solution and mix.
pH: 6.8 ± 0.2 at 25 °C.
The prepared medium in the tubes is clear and yellowish.

Experimental Procedure and Evaluation
After inoculation it is advised to cover the medium with a layer of paraffin viscous or agar.
Incubation: 24-48 hours at 35 °C aerobically.
Count the colonies which have grown and, if necessary, perform further tests