CULTURE MEDIA FOR CULTIVATION OF MICROORGANISMS 



261 



and 0.5% NaCl. Dissolve by gentle 

 heat. 



(7) Add N/1 NaaCOa until 0.8% acidity 

 is reached. 



(8) Boil or steam 20 or 30 minutes. 



(9) Filter. 



(10) Distribute into Fernbach flasks in 

 layers 2.5 ctm. deep. Each flask 

 should have two or three cotton- 

 plugged openings. 



(11) Add 0.1% glucose to each sterile flask 

 of (10) from a sterile 20.0% glucose 

 solution. 



Sterilization: Sterilize (10) by heating in 

 the autoclave at 110° to 115° for 30 

 minutes. Method of sterilization of glu- 

 cose solution not specified. 



Use: Cultivation of B. diphtheriae and 

 toxin production. Author reported that 

 the medium may be regarded as having 

 the maximum toxicity when reaction is 

 distinctly alkaline to phenolphthalein. 

 Other investigators used a similar me- 

 dium for different purposes. 



Variants : 



(a) Migula prepared a medium as follows: 



(1) Mix 500.0 g. of finely chopped lean 

 beef with one liter of water and 

 allow to stand in the ice box for 

 12 to 24 hours. 



(2) Press the liquid thru a towel and 

 make up the volume to 1 liter. 



(3) Boil in the steam cooker for 30 

 minutes. 



(4) The infusion may be boiled for an 

 hour before removing the meat 

 and then filtered thru paper. If 

 the liquid is still red, boil again 

 for 15 minutes. 



(5) Filter whey cold to remove the 

 fat. 



(6) Add 10.0 g. Witte peptone and 

 5.0 g. NaCl. 



(7) Neutralize by the addition of a 

 concentrated solution of Na2C03 

 until litmus is colored violet. 



(8) Add the desired amount of soda. 

 Generally, 10 cc. of 15.0% soda 

 solution is added per liter. 



(9) Boil and filter. 



(10) Add 1.0 or 2.0% glucose. 



(11) Distribute in tubes or flask. 



(12) Boil for one hour to sterilize. 



(b) Copeland and Boynton used a me- 

 dium prepared as follows to study 

 the Voges-Proskauer reaction by the 

 colon group. 



(1) Prepare an infusion from fresh 

 beef steak. 



(2) Dissolve 10.0 g. Witte's peptone, 

 5.0 g. NaCl and 10.0 g. of water- 

 free glucose in (1). 



(3) Adjust to 1.0% acid to phenol- 

 phthalein. 



(4) Sterilization not specified. 



(c) Avery and Cullen prepared a medium 

 as follows: 



(1) Prepare a beef infusion. 



(2) Dissolve 10.0 g. peptone, 10.0 g. 

 glucose and 5.0 g. NaCl in (1). 



(3) Adjust to pH = 7.6 to 7.8. 



(4) Tube and sterilize. 



They reported that in this medium 



the bovine type of Streptococcus 



haemolyticus gave a final pH of 4.3 



to 4.5 while a human type gave a final 



pH of 5.0 to 5.3. 



References: Smith (1899 p. 375), Migula 



(1901 p. 19), Copeland and Boynton (1905 



p. 242), Avery and Cullen (1919 p. 218). 



842. Mueller's Meat Infusion Broth 



Constituents : 



1. Water 1000.0 cc. 



2. NaCl 10.0 g. 



3. MgS04 0.4 g. 



4. CaCh 0.2 g. 



5. K2HPO4 2.0 g. 



6. Glucose 2.0 g. 



7. Phenol red (0.02% soln.) ... 80.0 cc. 



8. Meat infusion 1000.0 cc. 



9. Peptone 20.0 g. 



Preparation : 



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



(2) Mix equal parts (1) and meat infu- 

 sion, and add 1.0% peptone. (The 

 author added no peptone.) 



(3) Adjust to pH = 7.8. (No peptone 

 medium pH = 7.6.) 



Sterilization: Sterilize in autoclave at 10 

 pounds for 10 minutes. 



Use: To study the food requirements for 

 the growth of streptococci and pneumo- 

 cocci. The author reported that in the 

 above medium the peptone had little 

 influence on the growth. Using the media 



