CULTURE MEDIA FOR CULTIVATION OF MICROORGANISMS 



247 



(3) Make up the loss in weight by the 

 addition of water. 



(4) Neutralize to litmus, 



(5) Boil 5 minutes. 



(6) Make up the loss in weight by the 

 addition of water. 



(7) Adjust the reaction as desired 

 (+0.5 to +1.5%). 



(8) Filter thru paper. 



(9) Distribute into flasks or tubes. 

 (10) Sterilize (method not given). 



(n) Dopter and Sacquepee (1921) did not 

 specify the use of Liebig's meat ex- 

 tract, nor did they specify the 

 amount of NaCl or peptone used. 



(o) Stitt (1923) prepared the medium as 

 follows: 



(1) Place 3.0 g. Liebig's meat extract, 

 10.0 g. peptone, and 5.0 g. NaCl 

 in a mortar. 



(2) Dissolve the white of one or two 

 eggs in 1000.0 cc. of water. 



(3) Add (2) little by little to (1) until 

 a brownish solution is obtained. 



(4) Pour (3) into the inner compart- 

 ment of a rice cooker. 



(5) Apply heat to the outer compart- 

 ment containing NaCl or CaCl2. 



(6) Bring to a boil and boil for 15 to 

 20 minutes. Do not stir. 



(7) Place the inner compartment on 

 a scales, and its counterpoise and 

 a one kilo weight on the other side. 

 Add water to the medium until 

 the two arms balance. 



(8) Filter. 



(9) Sterilize in the autoclave at 115°C. 

 for 15 minutes or in the Arnold on 

 3 successive days. 



(10) The reaction rarely exceeds +0.75 

 (from +0.6 to +0.9) and does not 

 require adjusting. 



(p) Manwaring, Boyd and Okami (1923) 

 cultivated S. cholerae in a medium 

 containing 10.0 g. peptone, 2.5 g. 

 beef extract, and 5.0 g. NaCl per 

 liter. The reaction was adjusted to 

 be identical to that of Locke's solu- 

 tion (0.015% NaHCOs). 



(q) Park, Williams and Krumwiede (1924) 

 suggested the use of 2.0 to 5.0 g. 

 Armour or other commercial beef 

 extracts in addition to Liebig's 

 product. They used 5.0 g. NaCl, but 



did not specify the type of peptone 

 emploj'ed. 

 (r) Cunningham (1924) prepared the 

 medium as follows: 



(1) Weigh out 10.0 g. peptone, 5.0 g. 

 NaCl and 10.0 g. of Liebig's meat 

 extract. Weigh out the extract on 

 a piece of paper. 



(2) Place (1) into pot and add 

 1000.0 cc. of tap water. 



(3) Steam for an hour in a double 

 walled pot (one hour from the time 

 the water boils). 



(4) Add normal NaOH solution until 

 the liquid turns a piece of mois- 

 tened tumeric paper dipped into 

 it faintly but distinctly brown. 

 The reaction is acid to phenol- 

 phthalein, pH varies from 7.7 

 to 8.0. 



(5) Heat in an autoclave. 



(6) Filter thru gray coarse filter paper 

 until clear. 



(7) Make up the volume to 1 liter with 

 distilled water. 



(8) Tube in 8.0 cc. lots. 



(9) Sterilize at 22.5 pounds pressure. 

 References: Debrand (1900 p. 759), Smith 



(1902 p. 82), Frost (1903 p. 6), Roux and 

 Rochaix (1911 p. 108), Day and Baker 

 (1912-13 p. 435), Lohnis (1913 p. 14), 

 Rideal and Walker (1913 p. 575), Brussoff 

 (1916 p. 552), Berman and Rettger (1916 

 p. 537), Roddy (1917 p. 41), Brussoff 

 (1918 p. 205), Foster and Randall (1921 

 pp. 152, 153), Pitfield (1922 p. 114), Dopter 

 and Sacquepee (1921 p. 118), Stitt (1923 

 p. 33), Manwaring, Boyd and Okami (1923 

 p. 307), Park, Williams and Krumwiede 

 (1924 p. 97), Cunningham (1924 p. 11), 

 Besson (1920 p. 30), Harvey (1921-22 

 p. 68). 



806. Berman and Rettger's Extract Proteose 

 Solution 



Constituents : 



1. Water 1000.0 cc. 



2. Proteose 2.5, 5.0, 8.0 g. 



3. Beef e.xtract 2.5 or 5.0 g. 



4. NaCl 5.0 g. 



Preparation : 



(1) Prepare proteose by salting out the 

 proteose from commercial peptone 

 (details of the method not given). 



