l8o CULTURE MEDIA 



Media for anaerobic cultures. In addition to the 

 foregoing media, all of which can be, and are employed 

 in the cultivation of anaerobic bacteria, certain special 

 media containing readily oxidised substances are com- 

 monly used for this purpose. The principal of these 

 are as follows : 



Bile Salt Broth (MacConkey). 



1. Weigh out Witte's peptone, 20 grammes ( = 2 per cent.), 

 and emulsify with 200 c.c. distilled water previously warmed to 

 60 C. 



2. Weigh out sodium taurocholate (commercial), 5 grammes 

 ( = 0.5 per cent.), and glucose, 5 grammes ( = 0.5 per cent.), 

 and dissolve in the peptone emulsion. 



3. Wash the peptone emulsion into a flask with 800 c.c. distilled 

 water, and heat in the steamer at 100 C. for twenty minutes. 



4. Filter through Swedish filter paper into a sterile flask. 



5. Add sterile litmus solution sufficient to colour the medium 

 to a deep purple, usually 13 per cent, required. 



6. Fill, in quantities of 10 c.c., into tubes containing small 

 gas tubes (vide Fig. 104, page 161). Sterilise in the steamer at 

 100 C. for twenty minutes on each of three consecutive days. 



Glucose Formate Bouillon (Kitasato). 



1. Measure out nutrient bouillon, 1000 c.c. (vide page 163, 

 sections i to 6). 



2. Weigh out glucose, 20 grammes ( = 2 per cent.), sodium 

 formate, 4 grammes ( = 0.4 per cent.), and dissolve in the fluid. 



3. Tube, and sterilise as for bouillon. 



Glucose Formate Gelatine (Kitasato). 



1. Prepare nutrient gelatine (vide page 164, sections i to 7) and 

 measure out IOQO c.c. 



2. Weigh out glucose, 20 grammes ( = 2 per cent.), and sodium 

 formate, 4 grammes ( = 0.4 per cent.), and dissolve in the hot 

 gelatine. 



3. Filter through papier Chardin. 



4. Tube, and sterilise as for nutrient gelatine. 



Glucose Formate Agar (Kitasato). 



i. Prepare nutrient agar (vide page 167, sections i to 8). 

 Measure out 1000 c.c. 



2^ Weigh out glucose, 20 grammes ( = 2 per cent.), sodium 

 formate, 4 grammes ( = 0.4 per cent.) , and dissolve in the agar. 



3. Tube, and sterilise as for nutrient agar. 



