140 



CULTURE MEDIA FOR CULTIVATION OF MICROORGANISMS 



10.0 g. 

 0.1 to 1.0 g. 



4. MgC03 



5. Urea 



Preparation : 



(1) Dissolve 2 and 3 in part of 1. 



(2) Dissolve 4 in remainder of 1. 



(3) After sterilizing (1) and (2) mix 

 under aseptic conditions. 



(4) Add various quantities (0.1 to 1.0 g.) 

 sterile urea. 



Sterilization: Method not specified. 



Use: To study nitrogen oxidation by 



Nitrosohacter. 

 Reference: Fremlin (1903 p. 369). 



492. Wherry's Urea Solution 



Constituents: 



1. Redistilled water 1000.0 cc. 



2. NaoCOs 1.0 g. 



3. KCl 1.0 g. 



4. MgS04 1.0 g. 



5. CaCl2 1.0 g. 



6. Urea 2.0 g. 



7. KH2PO4 2.0 g. 



Preparation : 



(1) Dissolve 2, 3, 4, 5, 6 and 7 in 1. 



(2) Adjustment of reaction not given. 

 Sterilization: Sterilize in autoclave, time 



not given. 



Use : To study acid proofness of B. tubercu- 

 losis. Author reported that after the 

 sixth day all rods were non-acid-fast. 



Reference: Wherry (1913 p. 151). 



493. Evans' Urea Solution 



Constituents: 



1. Water 1000.0 cc. 



2. MgS04 1.0 g. 



3. K2HPO4 2.0 g. 



4. Urea 

 Preparation : 



(1) Dissolve 2 and 3 in 1. 



(2) No adjustment of reaction given. 



(3) Tube. 



(4) After sterilization add a small piece 

 of urea to each tube. 



Sterilization: Method of sterilization of the 

 solution not specified. Sterilize a piece 

 of solid urea by heating for 5 hour in a 

 toluene oven at 105°C. 



Use: To determine decomposition of urea. 



Reference: Evans (1916 p. 445). 



494. Percival's Urea Solution 



1000.0 cc. 



Constituents 

 1. Water. 



2. (NH4)2S04 2.0 g. 



3. K2HPO4 1.0 g. 



4. NaCl 2.0 g. 



5. MgS04 0.5 g. 



6. FeS04 0.4 g. 



7. MgCOs 10.0 g. 



8. Urea (0.01%) 0.1 g. 



Preparation : 



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



(2) Distribute in 50.0 cc. into conical 

 flasks. 



(3) Add 0.5 g. of basic MgCOj to each 

 flask. 



(4) To each flask add 0.01% urea. 

 Sterilization: Not specified. 



Use: To study nitrification by soil forms. 

 Variants: Percival added 0.03, 0.3, 1.0 or 



3.0% urea to each flask. 

 Reference: Percival (1920 p. 144). 



495. Murray's Glucose Urea Solution 



Constituents: 



1. Water 1000.0 cc. 



2. Glucose 100.0 g. 



3. K2HPO4 50.0 g. 



4. MgS04 0.5 g. 



5. Urea 10.0 g. 



Preparation : 



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



(2) Tube. 

 Sterilization: Not specified. 



Use: To study ammonification under either 



anaerobic or aerobic conditions. 

 Reference: Murray (1916 p. 602). 



496. Vierling's Glucose Urea Solution 



Constituents: 



1. Water 1000.0 cc. 



2. K2HPO4 lOg. 



3. CaCl2 0.1 g. 



4. MgS04 0.1 g. 



5. FeCla trace 



6. NaCl trace 



7. Glucose 10.0 g. 



8. Urea 10.0 g. 



Preparation: (1) Dissolve 2, 3, 4, 5, 6, 



7 and 8 in 1. 

 Sterilization: Not specified. 

 Use: Cultivation of mycobacteria. 

 Reference: Vierling (1920 p. 206). 



497. Thomas' Sucrose Urea Solution 



Constituents : 



1. Water 1000.0 cc. 



2. Sucrose 200.0 g. 



