248 



CULTURE MEDIA FOR CULTIVATION OF MICROORGANISMS 



(2) Dissolve 2.5, 5.0 or 8.0 g. of (1), 2.5 

 or 5.0 g. of beef extract and 5.0 g. 

 NaCl ia a liter of water. 

 Sterilization: Not specified. 

 Use: To study bacterial nutrition. 

 Reference: Berman and Rettger (1918 

 pp. 377-380). 



807. Guth's Selenium Extract Broth 



Constituents : 



1. Water 1000.0 cc. 



2. Meat extract (Liebig) . 10.0 g. 



3. Peptone (Witte) 10.0 g. 



4. NaCl 5.0 g. 



5. Sodium selenicate 



(Merck) 1.0 to 2.5 g. 



Preparation : 



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



(2) Adjust to neutral using litmus as an 

 indicator. 



(3) Dissolve 5.0 g. Merck's sodium 

 selenicate in 50.0 cc. distilled water. 



(4) Add normal HCl to (3) until the 

 reaction is neutral to litmus (requires 

 about 20.0 cc). 



(5) Make (4) up to 100.0 cc. 



(6) Heat in the autoclave for about 15 

 minutes. 



(7) Tube (1) in 10.0 cc. quantities. 



(8) Add 0.3 cc. of (6) to each tube of (7) . 

 Sterilization: Not specified. 



Use: Enrichment of typhoid bacilli. Colon 



bacilli are inhibited. 

 Reference: Guth (1915-16 p. 490). 



808. Berman and Rettger's Salt Extract 

 Broth 



Constituents : 



1. Water 1000.0 cc. 



2. Peptone (Witte) 5.0 g. 



3. Liebig's beef extract 2.5 g. 



4. NaCl 5.0 g. 



5. K2HPO4 1.0 g. 



6. MgS04 0.2 g. 



7. CaCl2 0.1 g. 



Preparation : 



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



(2) Tube in 10.0 cc. lots. 

 Sterilization: Not specified. 



Use: To study bacterial nutrition. 



Variants : The authors used Digestive Fer- 

 ments, Park Davis, Eimer and Amend's 

 peptone or Arlington Chemical Com- 



pany's amenoids instead of Witte's 

 peptone. 

 Reference: Berman and Rettger (1918 

 pp. 371-377). 



809. Berman and Rettger's Trypsinized 

 Extract Broth 



Constituents: 



1. Water 1000.0 cc. 



2. Beef e.xtract 2.5 g. 



3. NaCl 5.0 g. 



4. Peptone (Witte) 

 Preparation : 



(1) Prepare peptone digest by digesting 

 at 45°C. for several hours solutions 

 of Witte's peptone with commercial 

 trypsin. Then sterilize and add ex- 

 tract and NaCl. The amount of pep- 

 tone was not specified. 



(2) Tube in 10.0 cc. lots. 

 Sterilization: Method not given. 



Use: To study bacterial nutrition. Au- 

 thors reported that more nitrogen was 

 available in this medium than in similar 

 undigested media. 



Reference: Berman and Rettger (1918 

 pp. 383-384). 



810. Olszewski and Kohler's Trypsinized 

 Extract Broth 



Constituents : 



1. Water 1000.0 cc. 



2. Peptone 10.0 g. 



3. Liebig's meat extract 5.0 g. 



4. NaCl 5.0 g. 



5. Physiological salt solution. 3000.0 g. 

 Preparation : 



(1) Prepare ordinary nutrient bouillon 

 using 10.0 g. peptone, 5.0 g. Liebig's 

 meat extract and 5.0 g. NaCl. 



(2) Make alkaline by the addition of 

 7.0 cc. N/L soda solution after neu- 

 tralizing to litmus. 



(3) Boil. 



(4) Cool to 40°C. and add 0.2 g. trypsin, 

 10.0 cc. chloroform and 5.0 cc. toluol. 



(5) Place in a glass stoppered flask and 

 place in the incubator for 24 to 48 

 hours, shaking occasionally. 



(6) Filter thru a moistened folded filter 

 paper. 



(7) For use dilute one part of this stock 

 solution with 3 parts physiological 

 salt solution. 



