CULTURE MEDIA FOR CULTIVATION OF MICROORGANISMS 



661 



(20) Add the sterilized solution of agar 

 in quantities of 30.0 cc. to casein 

 digest already sterilized in quanti- 

 ties of 70.0 cc. in round quart 

 bottles. 



(21) Sterilize in autoclave. 

 Reference: Norris (1919-20 p. 541), Harvey 



(1921-22 p. 116). 



2053. Norris' Simplified Caseinogen Agar 



Constituents : 



1. Tap water (or saline) . 1000.0 cc. 



2. Caseinogen (10.0%).. 100.0 g. 



3. Washing soda (0.8%) . 8.0 g. 



4. Agar 20.0 to 40.0 g. 



5. Pancreatic extract 



(0.5%) 5.0 cc. 



Preparation : 



(1) Digest in an 0.8% aqueous solution 

 of washing soda, 10.0% of caseinogen 

 with 0.5% pancreatic extract at 

 37°C. for 24 hours. 



(2) Concentrate the products of digestion 

 on the water bath, yielding a paste 

 of the consistency and color of 

 Liebig's meat extract. This may be 

 further dried in a desiccator over 

 H2SO4 yielding a brittle resinous 

 mass which may be powdered. 



(3) To 1000.0 cc. of saline or tap water 

 add 100.0 g. (10.0%) of (2) to 40.0 g. 

 agar. 



(4) Adjust reaction to +10. Indicator 

 not specified. 



Sterilization: Method not given. 



Use : General culture medium. The author 

 suggested the term "trypsinoids" for the 

 digest (2). B. typhosus grew well on 

 this medium. Brewer's yeast and fresh 

 yeast were treated in like manner but 

 caseinogen was the more nutritive of 

 the two. 



Reference: Norris (1919-20 p. 706). 



2054. Teague and Deibert's Trypsinized 

 Casein Agar 



Constituents : 



1. Water 100.0 cc. 



2. Casein (10.0%) 10.0 g. 



3. Trypsin 



4. Agar solution 

 Preparation : 



(1) Prepare a 10.0% casein solution and 

 digest with trypsin at 37°C. for 8 days. 



Add chloroform to prevent bacterial 

 growth. 



(2) Boil (2) and filter thru cotton. 



(3) Add various amounts of sterile (2) 

 to an agar solution containing 20.0 g. 

 agar and 5.0 g. NaCl per liter. 



Sterilization: Sterilize (2) in the autoclave. 

 Sterilization of agar or final sterilization 

 not specified. 



Use: To study growth requirements of 

 Unna-Ducrey bacillus. Authors re- 

 ported that the medium did not support 

 growth. 



Reference: Teague and Deibert (1922 

 p. 70). 



2055. Sierakowski's Trypsinized Casein 



Lactose Agar 



Constituents : 



1. Water 1000.0 cc. 



2. Trypsinized casein (10.0%) . 100.0 g. 



3. Lactose (1.0%) 10.0 g. 



4. Brom thymol blue 0.3 g. 



5. Agar (2.0%) 20.0 g. 



Preparation : 



(1) Prepare a tryptic digest of casein and 

 adjust to pH = 7.0, Method of 

 preparation not given. 



(2) Dissolve 10.0% (1), 1.0% lactose, 2.0% 

 agar and 0.3 parts per 1000 brom 

 thymol blue in water. 



Sterilization: Not specified. 



Use: Isolation of colon-typhoid group. 

 Author reported that B. coli and lactose 

 fermenters gave yellow colonies. Ty- 

 phoid and non-lactose fermenters gave 

 blue colonies. Staphylococci and other 

 organisms resisting the gram stain were 

 inhibited. 



Reference: Sierakowski (1923 p. 1003). 



2056. Harvey's Trypsinized Caseinogen 



Blood Agar 



Constituents : 



1. Distilled water 100.0 cc. 



2. Blood (human or rabbit) 20.0 cc. 



3. Trypsinized caseinogen agar. 400.0 cc. 

 Preparation : 



(1) Add 20.0 cc. sterile human or rabbit 

 blood to 100.0 cc. distilled water in a 

 flask furnished with a rubber cork 

 and containing glass beads. 



(2) Shake vigorously to prevent forma- 

 tion of large fibrin masses. 



