CULTURE MEDIA FOR CULTIVATION OF MICROORGANISMS 



753 



Use: Cultivation of Oospora, fungi im- 

 perfecti. The authors reported that 

 gelatin was liquefied. 



Reference: Bobilioff-Preisser (1916 p. 400). 



2325. Beljerinck's Glucose Yeast Gelatin 



Same as medium 2081 but solidified by the 

 addition of 20.0% gelatin instead of agar. 



2326. Will's Sucrose Yeast Gelatin 



Constituents: 



1. Yeast water 1000.0 cc. 



2. Sucrose (6.0%) 60.0 g. 



3. Gelatin (10.0«%) 100.0 g. 



Preparation : 



(1) Add 6.0% sucrose and 10.0% gelatin 

 to neutral yeast water. 

 Sterilization: Not specified. 

 Use: Cultivation of non-spore forming 



saccharomyces. 

 Reference: Will (1908 p. 387). 



2327. Beljerinck's Urea Yeast Gelatin 



Constituents : 



1. Water 1000.0 cc. 



2. Y'east (pressed) 200.0 g. 



3. Urea 20.0 to 30.0 g. 



4. Gelatin 

 Preparation : 



(1) Prepare yeast water by boiling 200.0 

 g. pressed yeast with 1000.0 cc. water. 



(2) Add 2 or 3.0% urea and gelatin (amount 

 not specified) to (1). 



Sterilization: Not specified. 



Use: To show iridescence by urea splitting 

 organisms, Urococcus ureae and Uroba- 

 ,cillus pastenrii. Author reported that 

 when a urea splitting organism or a 

 particle of (NH4)2C03 was added to a 

 properly prepared plate, a characteristic 

 precipitate was formed. This was amor- 

 phous and stayed at first entirely on the 

 upper surface of the gelatin in a thin 

 sheet. This showed Newton's color rings. 

 As the layer grew it became thicker and 

 the edge spread over a greater surface 

 giving a color ring. After a time a white 

 precipitate formed in the depths of the 

 gelatin, which assumed the shape of 

 plano-convex lens. Non-urea splitting 

 organisms did not show this. Tausz and 

 Peters cultivated paraffin bacteria and 



Vierling studied urease production by 

 mycobacteria on similar media. 

 Variants : 



(a) Tausz and Peters cultivated Bac- 

 terium aliphaticum, Bacterium ali- 

 phaticum liquefaciens, on the follow- 

 ing medium: 



(1) Boil 100.0 g. pressed yeast in 500.0 

 cc. water. 



(2) Dissolve 50.0 g. of gelatin in (1). 



(3) Adjustment of reaction not given. 



(4) Sterilize on 3 successive days in 

 streaming steam. 



(5) To determine the production of 

 urease, add 1.25 g. sterile urea to 

 the medium. 



(b) Vierling studied urease production 



by mycobacteria on a medium 

 prepared as follows: 



(1) Boil 200.0 g. pressed yeast with 

 1000.0 cc. of water. 



(2) Cool, decant and filter. 



(3) Dissolve 25.0 g. urea and 100.0 g. 

 gelatin in the filtrate. 



(4) Sterilize (Method not given). 



(5) Pour in plates. 



References: Beijerinck (1901 p. 39), Tausz 

 and Peters (1919 p. 49), Vierling (1920 p. 

 205). 



2328. Will's Basal Wort Gelatin 



Constituents : 



1. Wort Gelatin (10.0%). 

 Preparation : 



(1) Prepare 10.0% wort gelatin. 



(2) Dissolve one of the added nutrients 

 in (1). 



Sterilization: Not specified. 



Use: Cultivation of mycoderma-like or- 

 ganisms. Park, Williams and Krum- 

 wiede used a similar medium for the 

 cultivation of molds. 



Added nutrients: The author added 0.7% 

 asparagin or 1.0% ammonium tartrate. 



Variants : 



(a) Will used the 10.0% wort gelatin 

 without any additions. 



(b) Park, Williams and Krumwiede added 

 2.0% of any desired carbohydrate to 

 beerwort, solidified by the addition of 

 10.0% gelatin. 



References: Will (1900 p. 597), (1910 p. 3), 

 Park, Williams and Krumwiede (1924 p. 

 134). 



