526 



CULTURE MEDIA FOR CULTIVATION OF MICROORGANISMS 



(3) Strain and heat in water bath to 

 boiling and strain again. 



(4) Dissolve 3 and 4 in (3). 



(5) Adjust to pH = 7.5. 



(6) Filter and autoclave at 15 pounds 

 pressure for 30 minutes. 



(7) Dry agar thoroly, weigh and wash in 

 running water over night. 



(8) Dissolve 60.0 g. (7) in 1000.0 cc. of 

 water in the autoclave. 



(9) Adjust to pH = 7.5 and clear by 

 straining through cotton and gauze. 



(10) Add glucose to (6) just before addi- 

 tion of agar solution. 



(11) In making the mixtures the amount 

 of hot fluid, 6.0% agar, necessary to 

 obtain the various percentages, is 

 diluted with hot distilled water to 

 a volume equal to that of the double 

 strength broth (9) also hot, and 

 mixed. 



(12) Check reaction (pH = 7.5). 

 Sterilization: Sterilize in autoclave at 



15 pounds for 20 minutes. 



Use: To study growth at different agar 

 concentrations. The author recom- 

 mended a 0.1% agar concentration for 

 growth of aerobic and anaerobic bacteria. 



Reference: Kitchens (1921 p. 391). 



1724. Jackson and Muer's Liver Infusion 

 Agar 



Constituents : 



1. Water 1000.0 cc. 



2. Liver, beef 500.0 g. 



3. Agar 5.0 g. 



4. Peptone (Witte's) 10.0 g, 



5. Glucose 10 g 



6. K2HPO4 1.0 g. 



Preparation : 



(1) Chop 500.0 g. beef liver into small 

 pieces, add 500.0 cc. distilled water 

 and boil slowly for two hours, stir- 

 ring occasionally. 



(2) Add 3 (dried at 105°C. for 30 minutes) 

 to 500.0 cc. distilled water and digest 

 for 30 minutes in an autoclave at 

 120°C. (15 pounds). 



(3) After making up the loss by evapora- 

 tion, strain the liver infusion thru a 

 wire strainer, add 500.0 cc. filtrate to 

 the agar solution. 



(4) To the filtrate add 4 and 5, then (2). 

 Weigh the infusion and container. 



(5) After warming this mixture in a 

 double boiler and stirring it for a 

 few minutes to dissolve ingredients, 

 titrate with N/20 sodium hydrate, 

 using phenolphthalein as an indicator, 

 and neutralize with normal sodium 

 hydrate. 



(6) Boil vigorously for 30 minutes in a 

 double boiler, and 5 minutes over a 

 free flame with constant stirring to 

 prevent the caramelization of the 

 dextrose. 



(7) Make up any loss in weight by evapo- 

 ration and filter thru cotton flannel 

 and filter paper. 



(8) Tube. 



Sterilization: Sterilize in an autoclave for 

 15 minutes. 



Use: Cultivation of B. sporogenes and 

 other bacteria. Medium also used for 

 presumptive test for B. coli in water 

 analysis. 



Variants: Harvey solidified medium 833 

 variant (a) by the addition of agar. He 

 reported that when 1.0 acid, B. bifidus 

 grew on this medium. When 4.0% acid 

 B. acidophilus grew on this medium. 



References : Jackson and Muer (1911 p. 290), 

 (1911 p. 929), Harvey (1921-22 p. 110). 



1725. Hall's Testicular Infusion Agar 

 Constituents : 



1. Distilled water 1000.0 cc. 



2. Testicles, beef 500.0 g. 



3. Peptone (Witte or Difco) . . 20.0 g. 



4. Agar 30.O g. 



5. Glucose 5.0 g. 



6. NaH2P04 3 0g. 



Preparation : 



(1) Soak over night, 500.0 g. of ground 

 beef testicles from which the tunica 

 vaginalis has been stripped, in 

 1000.0 cc. distilled water at room 

 temperature. 



(2) Heat to 50°C. Keep warm in 37° 

 incubator for one hour. 



(3) Boil— strain, and restore to 1000.0 cc. 

 If in excess do not boil to reduce 

 volume, — overheating is injurious. 



(4) Add 3, 4, 5 and 6 to (3). 



(5) Soak at least an hour to soften the 

 agar. 



(6) Melt in autoclave at 10 pounds for 

 30 minutes. 



