CULTURE MEDIA FOR CULTIVATION OF MICROORGANISMS 



509 



gentian violet (improved Coleman 



Bell). 

 Sterilization: Sterilize in the autoclave. 

 Use: Isolation and cultivation of B. pestis. 

 Reference: Meyer and Batchelder (1926 

 p. 385). 



1685. Miiller's Indicator Infusion Agar 



Same as medium 784 but solidified by the 

 addition of 18.0 g. of agar per liter. 



1687. Friedberger and Joachimoglus' Tellu- 

 rite Placenta Infusion Agar 

 Constituents: 



1. Placenta infusion agar. 100.0 cc. 



2. Potassium tellurite 



(1.0%) 1.0 to 2.0 cc. 



Preparation : 



(1) Prepare neutral placenta infusion 

 agar. 



(2) Add from 1.0 to 2.0 cc. of a 1.0% po- 

 tassium tellurite solution to each 

 100.0 cc. of (1). 



Sterilization: Method not specified. 



Use; Cultivation of Bacillus typhi exan- 

 thematici {Bacillus proteus, Weil and 

 Felix). This organism produces an in- 

 tense black color on this medium. 



Reference: Friedberger and Joachimoglu 

 (1918 p. 805). 



1688. Ragit Agar 



Constituents: 



1. Water 1000.0 cc. 



2. Ragit agar 42.0 g. 



Preparation: (1) Dissolve 42.0 g. of Ragit 



agar in 1000.0 cc. of water. Ragit agar is 

 a trade name of a dried medium marketed 

 by Merck. It contains "Maggibouillon" 

 Agar and Peptone in such amounts that 

 42.0 g. of powder in 1 liter of water gives 

 a nutrient agar of the usual composition, 

 (i e. Beef infusion with 1.0% peptone 

 and 2.0% agar.) 

 Sterilization: Not specified. 

 Use: General culture medium. 

 Variants : 



(a) Tausz and Peter cultivated Bac- 

 terium aliphaticum, Bacterium ali- 

 phaiicum Uquefaciens and Paraffin 

 bacteria, and prepared the medium 

 as follows: 

 (1) Boil 42.0 g. Ragit agar with 1 liter 

 of water for one hour. 



(2) The reaction is slightly alkaline. 



(3) Filter in the steamer. 



(4) Sterilize on three successive days 

 for 30 minutes in streaming steam. 



(b) Muller dissolved 22.0 g. Ragit bouil- 

 lon and 10.0 g. agar in 1000.0 cc. water 

 to cultivate milk bacteria. The reac- 

 tion was slightly alkaline. 

 References: Marx (1910 p. 361), Lohnia 



(1913 p. 17), Tausz and Peter (1919 p. 507), 



Muller (1917 p. 390). 



1689. Bacto Nutrient Agar (Dehydrated) 



Constituents : 



1. Distilled water 



2. Beef extract (Bacto) 3.0 g. 



3. Peptone (Bacto) 5.0 g. 



4. Agar (Bacto) 15.0 g. 



Preparation : 



(1) Dissolve 23.0 g. of Bacto Nutrient 

 Agar (Dehydrated) in 1000.0 cc. dis- 

 tilled water by boiling or autoclaving. 



(2) Restore loss if necessary. 



(3) If sterilized 20 minutes at 15 pounds 

 pressure pH = 6.6±. 



Sterilization : Sterilize in the usual manner. 



Use: General culture medium. The me- 

 dium conforms to "Standard Methods" 

 formula. 



Reference: Digestive Ferments Co. (1925 

 p. 10). 



1690. Bacto Nutrient Phosphate Agar 

 (Dehydrated) 



Constituents : 



1. Distilled water 



2. Beef extract (Bacto) 3.0 g. 



3. Peptone (Bacto) 10 g. 



4. Agar (Bacto) 15.0 g. 



5. NaaHPOi 5.0 g. 



Preparation : 



(1) Dissolve 33.0 g. of Bacto Nutrient 

 Phosphate Agar (Dehydrated) in 

 1000 cc. distilled water by boiling or 

 autoclaving preferably by boiling. 



(2) If sterilized 20 minutes at 15 pounds 

 pressure pH = 7.5 ±. 



(3) Cool to 50°C. before adding albu- 

 minous enrichment materials if these 

 materials are to be added. 



Sterilization: Sterilize in the usual manner. 

 Use : General culture medium. 

 Reference: Digestive Ferments Co. (1925 

 p. 11). 



