18 LABORATORY MANUAL OF MICROBIOLOGY 



Medium 32 

 Synthetic Solution for Yeast^ 



Sucrose 50.0 gm. 



Ammonium sulphate ((NH4)2S04) 6.0 gm. 



Mono-ammonium phosphate (NH4H2PO4) 2.0 gm. 



Potassium sulphate (K2SO4) 4.0 gm. 



Magnesium sulphate (MgS04-7H20) 2 . 25 gm. 



Calcium sulphate (CaS04) 2 . 25 gm. 



Tap water 1,000.0 cc. 



1 Hayduck, F., U. S. Patent, Reissue 15, 716. 



Medium 33 

 Carrot Extract Agar for Spore Formation of Yeasts 



Carrots 1,000.0 gm. 



Calcium sulphate (CaS04-2H20) 10.0 gm. 



Agar 20.0 gm. 



Water 200 to 300 cc. 



Wash and grind the carrots in a meat chopper. Add 200 to 

 300 cubic centimeters of tap water and boil for about 10 minutes. 

 Filter through cheesecloth. Add the calcium sulphate and agar 

 and heat in steamer for 30 minutes. Tube for slopes and sterilize 

 at 15 pounds for 15 to 20 minutes. 



MEDIA FOR ACTINOMYCES^ 

 Medium 34 



Nitrate-sucrose Agar^ 



Agar 15.0 gm. 



Sodium nitrate (NaNOs) 2.0 gm. 



Dipotassium phosphate (K2HPO4) 1.0 gm. 



Magnesium sulphate (MgS04-7H20) 0.5 gm. 



Potassium chloride (KCl) 0.5 gm. 



Ferrous sulphate (FeS04-7H20) 0.01 gm. 



Sucrose 30.0 gm. 



Water 1,000.0 cc. 



Reaction approximately pH 7.0. 



2 For the cultivation of acid-resisting actinomyces, the reaction of these 

 media as well as of medium 17 should be adjusted to pH 4.0. Jensen, H. 

 L., Soil Sci. 25 : 225, 1928. 



3 Waksman, S. a., Soil Sci., 8: 71-215, 1919. 



