CULTURE MEDIA FOR CULTIVATION OF MICROORGANISMS 



415 



4. MgCO3(1.0%). lOg. 



5. Agar 15.0 g. 



Preparation: 



(1) Dissolve 2 and 3 in 1. 



(2) Add 5 and boil. 



(3) Tube. 



(4) Add 1.0% sterile MgCOa to sterile 

 (3). 



Sterilization: Method of sterilization of (3) 

 or MgCOa not given. 



Use: Isolation of nitroso bacteria and to 

 study nitrogen oxidation by them. 

 Author reported that colonies appeared, 

 when eye was nearly on the level with the 

 colony, as a colorless, ground glass mass 

 1.0 mm. or more in diameter. Colonies 

 in the depth of medium appeared as 

 points to the naked eye. 



Variants: Gage prepared the medium as 

 follows: 



(1) Wash agar agar ten times in water 

 to remove all nitrogenous material. 



(2) Dissolve 1.0 g. (NH4)2S04, 1.0 g. 

 potassium phosphate and 15.0 g. of 

 (1) in 1000.0 cc. of nitrite free water. 



(3) Dissolve 1.0 g. MgCOs in 100.0 g. 

 nitrite free water. 



(4) Sterilize (2) and (3) separately. 



(5) Mix (2) and (3) under aseptic con- 

 ditions. 



References: Fremlin (1903 p. 375), Gage 

 (1910 p. 15). 



1418. Nencki, Sieber and Wyzniklewlcz's 

 Ammonium Sulphate Agar 



1000.0 cc. 

 10.0 to 15.0 g. 

 0.5 g. 

 1.0 g. 

 2.5 g. 

 5.0 to 10.0 g. 



Constituents : 



1. Water 



2. Agar 



3. K2HPO4. 



4. NajCOa 



5. (NH4)2S04 



6. NaCl 



Preparation : 



(1) Soak 10.0 to 15.0 g. agar with 2 or 3 

 times the volume of distilled water. 



(2) Dissolve the agar in 1000.0 cc. of hot 

 water. 



(3) Adds, 4, 5 and 6 to (2). 



(4) Filter. 



Sterilization: Sterilize in the autoclave. 



Use : Study cause of cattle plague. Author 



^ reported that medium when inoculated 



with cattle plague containing material 



after two days showed 1-3m round cells. 



Reference: Nencki, Sieber and Wyzni- 

 kiewicz (1898 p. 530). 



1419. Gowda's Ammonium Sulphate Agar 



Constituents: 



1. Conductivity water. 



2. K2HPO4. 



3. (NH4)2S04. 



4. MgS04. 



5. FeS04. 



6. NaCl. 



7. NajCOa. 



8. Agar. 

 Preparation : 



(1) Soak agar in water for 8 to 10 days. 



(2) Dissolve agar in water. 



(3) Pour in plates, and while still liquid 

 add the salts as indicated in the table. 



(4) The table at top of page 416 gives the 

 amounts of salts used, sterilization, 

 and amount of solution added to each 

 agar plate. 



Sterilization: Indicated in table. 

 Use: To study nitrification. 

 Reference: Gowda (1924 p. 253). 



1420. Helnemann's Ammonium Sulphate 

 Agar 



Constituents: 



1. Distilled water 1000.0 cc. 



2. FeS04 0.4 g. 



3. MgSOi 0.5 g. 



4. K2HPO4 10 g. 



5. NaCl 2.0 g. 



6. (NH4)2S04 10 g. 



7. Agar 20.0 g. 



8. CaCOa, 10.0 g. 



Preparation : 



(1) Dissolve 2, 3, 4, 5 and 6 in 1. 



(2) Dissolve 20.0 g. of agar in (1). 



(3) Add 10.0 g. precipitated CaCOs to (2). 



(4) Shake well. 



(5) Tube. 



Sterilization: Sterilize in the autoclave. 

 Use: To study nitrification. 

 Reference: Heinemann (1922 p. 38). 



1421. Committee S. A. B. Basal Ammonium 

 Phosphate Agar 



Constituents: 



1. Water 1000.0 cc. 



2. KCl 0.2 g. 



3. NH4H2PO4 10 g. 



