58 



CULTURE MEDIA FOR CULTIVATION OF MICROORGANISMS 



3. NaCl 0.5 g. 



4. Maltose 1.0 g. 



Preparation : 



(1) Dissolve 2, 3 and 4 in 1000.0 g. of 

 nitrite free water. 



(2) Distribute in 100.0 cc. lots in 150.0 

 cc. flasks. 



Sterilization: Not specified. 



Use: To study the fixation of nitrogen by 



nitroso bacteria. No nitrogen was fixed 



by the culture studied. 

 Reference: Gage (1910 p. 19). 



184. Sohngen's Colloid Mannitol Solution 



Constituents : 



1. Water 1000.0 cc. 



2. Mannitol 20.0 g. 



3. K2HPO4 0.5 g. 



4. Iron aluminum silicon about 0.1 g. 



5. Colloidal material 

 Preparation : 



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



(2) After sterilization add one of the 

 following sterile materials to 100.0 

 cc. of (1). 



(a) 2.0 g. raw humus (prepared by 

 sieving and washing soil, moisten 

 with several drops of soda solution) . 



(b) 400 mg. of humus acid containing 

 traces of iron, aluminum and 

 silicon. 



(c) 500 mg. colloidal silicon dioxide as 

 a sol. 



(d) 400 mg. Thompson phosphate. 



(e) 200 mg. purified potassium humate. 



(f) 500 mg. of iron oxide as a sol. 

 Sterilization: Method not given. 



Use: To study the effect of colloids on bac- 

 terial processes (nitrogen assimilation) 

 by azotobacter. The most nitrogen was 

 assimilated in the presence of raw humus 

 and silicon dioxide. 



Reference: Sohngen (1913 p. 627). 



185. Beijerinck's Phosphate Glucose 

 Solution 



Constituents: 



1. Water 1000.0 cc. 



2. Glucose 20.0 g. 



3. K2HPO4 0.2 g. 



4. CaC03 20.0 g. 



Preparation : 



(1) Dissolve 2 and 3 in 1. 



(2) Add 4 to (1). 



Sterilization: Not specified. 



Use: Growth of mesonitrophilic organisms, 

 Azotobacter agilis, Granulobacter spher- 

 icum. When inoculated with pasteurized 

 garden soil after 2 or 3 days a fermenta- 

 tion takes place. The odor of ethyl or 

 propyl alcohol is given off. 



Variants: (1) Bonazzi specified the use of 

 deep well water and added 0.5 g. CaCOa 

 for each 100.0 cc. of medium. He also 

 specified that 1.246 g. Ca(N03)2 might be 

 added if desired. 



Reference: Beijerinck (1901 p. 573), Bo- 

 nazzi (1921 p. 336). 



186. Buhlert and Fickendey's Phosphate 



Glucose Solution 



Constituents: 



1. Water 1000.0 cc. 



2. K2HPO4 1.0 g. 



3. Glucose 20.0 g. 



4. NaCl 1.0 g. 



5. CaCOs 4.0 g. 



Preparation : 



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



(2) Distribute in large Erlenmeyer flasks. 

 Sterilization: Not specified. 



Use : To study nitrogen fixation by bacteria 



from the soil. 

 Variants : 



(a) Barthel used 10.0 g. CaCOs. 



(b) Percival used 5.0 g. CaCOs. 

 References: Buhlert and Fickendey (1906 



p. 403), Barthel (1910 p. 122), Percival 

 (1920 p. 209). 



187. Wojtkiewicz's Mannitol Salt Solution 



Constituents: 



1. Water 1000.0 cc. 



2. Mannitol 20.0 g. 



3. K2HPO4 0.2 g. 



4. Chalk 5.0 g. 



Preparation : 



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



(2) Distribute in 125.0 cc. lots in 500.0 cc. 

 Erlenmeyer flasks. 



Sterilization: Not specified. 



Use: To study nitrogen assimilation by 



bacteria from the soil. 

 Variants : 



(a) Hanzawa used 0.5 g. K2HPO4 and 

 did not specify the amount of chalk 

 to be added. 



(b) Hanzawa suggested the use of soil 



