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CULTURE MEDIA FOR CULTIVATION OF MICROORGANISMS 



1479. Tausz and Peter's Napthenate 

 Ammonium Phosphate Agar 



Constituents : 



1 Water 1000.0 cc. 



2. MgNH4P04 (0.1%) 10 g. 



3. CaS04 (0.01%) 0.1 g. 



4. K2HPO4 (0.08%) 0.8 g. 



5. FeCla trace 



6. KI ti-a'^e 



7. Agar •■ 15-0 g- 



8. Sodium salt of napthenic 

 acid lO.Og. 



Preparation : 



(1) Cut agar into small pieces, mix with 

 water and allow to stand (time not 

 specified). 



(2) Wash with flowing water on a filter 

 for several days. 



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



(4) Add 1.0 g. of the sodium salt of 

 napthenic acid to each 100.0 cc. of (3). 



Sterilization: Not specified. 



Use : Cultivation of paraflBn bacteria, Bac- 

 terium aliphaticum, Bacterium alipha- 

 ticum liquefaciens . 



Reference: Tausz and Peters (1919 p. 49). 



1480. Simmons' Citrate Agar 



Constituents : 



1. Distilled water 1000.0 cc. 



2. Agar 20.0 g. 



3. NaCl 5.0 g. 



4. MgS04 0.2 g. 



5. (NHOHsPOi 10 g- 



6. K2HPO4 10 g- 



7. Sodium citrate (2.77 g. of 

 sodium citrate, 5^ H2O) . . . . 2.0 g. 



8. Brom-thymol blue (1.5% 

 alcoholic) 10-0 cc. 



Preparation : 



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



(2) Add 20.0 g. clean washed agar and 

 autoclave at 15 pounds pressure for 

 15 minutes. 



(3) Adjust to pH = 6.8. 



(4) Add 8. 



(5) Tube and slant. 



Sterilization: See step (2) above. 



Use: Differentiation of typhoid-colon aero- 

 genes group. The author reported that 

 Escherichia coli was markedly or com- 

 pletely inhibited and does not change the 

 color of the medium. Aerobacter aero- 



genes grew luxuriantly, forming large 

 greenish blue colonies, producing a blue 

 color in the medium. 



Variants: The dye used in the medium 

 above was a product of National Anilin 

 and Chemical Company. A 0.4% aque- 

 ous solution of brom-thymol blue may 

 be used in the proportions of 20.0 cc. per 

 liter of agar. The aqueous solution is 

 prepared by grinding 0.1 g. of dry powder 

 in an agate mortar with 3.2 cc. of N/20 

 NaOH and when solution is complete 

 dilute to 25.0 cc. with water. The brom- 

 thymol blue distributed by the Lamotte 

 Chemical Products Company gave satis- 

 factory results when used in these pro- 

 portions. 



Reference: Simmons (1926 p. 209). 



1481. Dolt's Lactose Ammonium Phosphate 

 Agar 



Constituents : 



1. Distilled water 1000.0 cc. 



2. Agar (purified) 30.0 g. 



3. Glycerol ^.0 g. 



4. Ammonium phosphate 1.0 g. 



5. Lactose 10-0 g. 



6. Azolitmin 10 g. 



Preparation : 



(1) Purify agar by cutting it in small 

 pieces and soaking it in distilled water 

 24 hours. 



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



(3) Add NaOH until neutral to phenol- 

 phthalein. 



(4) Dissolve 5 in (3). 



(5) Dissolve l.C g. of Kahlbaum's C. P. 

 azolitmin in 100.0 cc. distilled water 

 and boil, 15 minutes. This gives a 

 blue solution. 



(6) Add 10.0 cc. of (5) to (4). 

 Sterilization: Method not given. 



Use : Detection of acid production in water 

 analysis. Author reported that B. coli 

 produced a red colony on this medium. 

 Bengis cultivated B. coli on a similar 

 medium. 



Variants: Bengis prepared a medium as 

 follows: He employed the medium to 

 cultivate large numbers of B. coli: 



(1) Dissolve 30.0 g. of agar in distilled 

 water. 



(2) Add 10.0 g. glycerol and 2.0 g. 



