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CULTURE MEDIA FOR CULTIVATION OF MICROORGANISMS 



(c) Water blue. 



(d) Berlin blue. 



(e) Gentian violet. 



(f) Methyl violet. 



(g) Crystal violet. 

 (h) Fuchsin. 



(i) Methyl green, 

 (j) Malachite green, 

 (k) Iodine green. 

 (1) Guignets-green. 

 (m) Acid violet, 

 (n) Acid fuchsin. 

 (o) Phlexin red. 

 (p) Magdali red. 

 (q) Erythrosin. 

 (r) Benzoazurin. 

 (s) Benzopurpurin. 

 (t) Indulin. 

 (u) Nigrosin. 

 (v) Aniline blue, 

 (w) Corallin. 



(x) Noggerath's color mixture. 

 (y) Chrysoidin. 

 (z) Ruby S. 

 (aa) Kongo red. 

 (bb) Dahlia, 

 (cc) Victoria blue, 

 (dd) Indigo carmine, 

 (ee) Orseille-extract. 

 (ff) Tcluidin, 

 (gg) Magenta red. 

 (hh) Bismarck Brown, 

 (b) Hunter added 0.1 to 0.5 cc. of a con- 

 centrated watery solution of neutral 

 red to nutrient agar. 

 References : Rothberger (1898 pp. 515, 517), 

 (1899 p. 72), Hunter (1901 p. 614). 



1717. Omelianski's Indicator Agar 

 Constituents : 



1. Nutrient agar 1000.0 cc. 



2. Methylene blue (1.0% solution) 

 Preparation: (1) Add 10 drops of a 1:100 



solution of methylene blue to agar. 



Sterilization: Not specified. 



Use: Differentiation of Bad. coli and Bac. 

 typhi. Author reported that coli gives 

 decolorization after 6-7 hours. Typhoid 

 colonies show no decolorization until 

 later. (See variant.) 



Variants: The author added 0.1 cc. of a 

 sterile 2.0% indigo-carmine solution to 

 10.0 cc. of sterile melted (not hot) agar. 

 The medium was used for the differentia- 

 tion of Bad. coli and Bad. typhi, Bac. 



diphtheriae and Bac. Pseudodiphtheriae. 

 The author reported that coli organisms 

 changed the blue agar to yellow after 

 15 to 20 hours. Typhoid organisms 

 decolorized the agar after 3 or 4 days. 

 Bac. pseudodiphtheriae grew very luxu- 

 riantly with yellow colonies, and after 

 2-3 days caused a decolorization nearly 

 as intense as Bad. coli. Bac. diphtheriae 

 grew less abundantly and did not cause 

 decolorization. 

 Reference: Omelianski (1903 p. 4). 



1718. Burnet and Weissenbach's Lead 

 Acetate Agar 



Constituents : 



1. Nutrient agar. 



2. Lead acetate. 

 Preparation : 



(1) Preparation of agar not given. 



(2) Prepare a 1:10 solution of neutral 

 lead acetate in water. 



(3) Add under aseptic conditions one 

 drop of freshly prepared sterile (2) to 

 each tube containing 4.0 cc. of melted 

 sterile (1). 



(4) Mix well. 



(5) Slant. 



Sterilization: Sterilize (1) and (2) sepa- 

 rately; method not given. 



Use: HoS production. Author reported 

 that the medium is darkened if HoS is 

 formed. Paratyphoid B and typhoid 

 bacillus formed HoS. Paratyphoid A did 

 not produce HoS. 



Variants: Thompson prepared a similar 

 medium as follows: 



(1) Exact composition of Standard 1.5% 

 agar not specified but it is to be 

 prepared using "Difco" peptone. 



(2) Adjust to pH 6.8 or 7.0. 



(3) Distribute in 100.0 cc. lots in flasks. 

 Method of sterilization not given. 



(4) Prepare a 2.0% aqueous solution of 

 Merck's subacetate. Store in a 

 tightly stoppered bottle. This solu- 

 tion may be kept several weeks under 

 these conditions. 



(5) Just before use melt (3) and add to 

 each 100.0 cc. lot, 20.0 cc. of (4). 



(6) Distribute into sterile tubes, inocu- 

 late and pour into sterile plates. 



References : Burnet and Weissenbach (1915 

 p. 567), Thompson (1920-21 p. 384). 



