CULTURE MEDIA FOR CULTIVATION OF MICROORGANISMS 



245 



3. Meat extract. 



4. KNO3. 

 Preparation : 



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



(2) Reaction to be slightly alkaline. 



(3) Distribute in 10.0 cc. lots. 

 Sterilization: Method not given. 

 Use: To study denitrification. 

 Variants : 



(a) von Caron used 6.0 g. Liebig's Meat 

 extract, 6.0 g. peptone and 2.0 g. 

 KNO3 per liter. 



(b) Tanner used 3.0 g. Liebig's meat 

 extract, 10.0 g. Witte's peptone and 

 3.0 g. KNO3 per liter. 



(c) Committee S. A. B. used 0.1% KNO3, 

 3.0 g. beef extract and 5.0 g. peptone 

 per liter. 



(d) Percival used 3.0 g. sodium nitrate, 

 5.0 g. Lemco meat extract and 10.0 g. 

 peptone per liter. 



References : Stutzer (1901 p. 83), von Caron 

 (1912 p. 70), Tanner (1919 p. 45), Com- 

 mittee S. A. B. (1920 p. 128), Percival 

 (1920 p. 165). 



804. Davis and Ferry's Nitrate Bouillon 

 Extract Broth 



Constituents : 



1. Water 1000.0 cc. 



2. Peptone 20.0 g. 



3. Meat extract (Liebig's) .... 10.0 g. 



4. NaCl 4.0 g. 



5. K2HPO4 3.0 g. 



6. MgS04 0.4 g. 



7. KNO3 0.2 g. 



Preparation : 



(1) Dissolve 2.0% peptone in 500.0 cc. 

 water. 



(2) Dissolve 1.0% Liebig's meat extract 

 in 500.0 cc. water. 



(3) Mix (1) and (2). 



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



(5) Add sufficient normal NaOH to give a 

 final pH = 8.0 to 8.2. 



(6) Steam 15 minutes. 



(7) Check the reaction. 



(8) Distribute as desired. 

 Sterilization: Sterilize at 115° for 20 



minutes. 

 Use: Cultivation of Bad. diphtheriae and 



toxin production. Author reported fair 



growth. 

 Reference: Davis and Ferry (1919 p. 236). 



805. Debrand's Extract Broth 

 Constituents : 



1. Water 1000.0 cc. 



2. NaCl 5.0 g. 



3. Peptone (Chapoteaut) 10.0 g. 



4. Meat extract (Liebig) 5.0 g. 



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

 Sterilization: Not specified. 



Use: Debrand used the medium for the 

 enrichment of the tetanus bacillus. The 

 medium was inoculated with soil that had 

 been heated on each of 3 successive days 

 at 100°C. for 2 minutes. Other investi- 

 gators used the medium as a general 

 culture medium. 



Variants : 



(a) Smith (1902) did not specify the type 

 of peptone or meat extract used, and 

 prepared the medium as follows : 



(1) Dissolve 2, 3 and 4 in 1 by heating 

 gently and stirring with a glass 

 rod. 



(2) Boil for 5 to 10 minutes, stirring 

 constantly. 



(3) Filter thru paper. 



(4) Cool and make up to 1 liter. 



(5) Adjust the reaction. 



(6) Boil. 



(7) Filter. 



(8) Distribute 



(9) Sterilize by the fractional method 

 in steam at 100°C. or in the auto- 

 clave at 120°C. 



(b) Frost (1903) used 3.0 g. Liebig's beef 

 extract, and 1.0% Witte's peptone 

 and prepared the medium as follows: 



(1) Weigh out 3.0 g. of beef extract 

 such as Liebig's. 



(2) Add a liter of distilled water. 



(3) Place in a cooking vessel. 



(4) Add 1.0% peptone (Witte) and 

 0.5% NaCl to (3). 



(5) Weigh the solution and the vessel. 



(6) Heat to not above 60°C. until the 

 ingredients are in solution. 



(7) Restore the loss in weight by the 

 addition of distilled water. 



(8) Neutralize to phenolphthalein by 

 the addition of normal NaOH. 



(9) Boil for 5 minutes and restore the 

 weight. 



(10) Test for reaction and readjust if 

 necessary, 



(11) Add 0.5% to 1.5% of normal HCl. 



