300 DIFCO MANUAL 



produces a purified casein of uniform quality. Casein Purified is soluble in dilute 

 solutions of sodium hydroxide forming the sodium salt. 



CASEIN TECHNICAL, DIFCO (B337) 



Casein Technical is a technical grade of this protein recommended for use 

 in the preparation of culture media, and in other techniques not requiring a 

 purified product. 



SODIUM CASEINATE, DIFCO (B187) 



Sodium Caseinate is a valuable ingredient of many culture media. It has 

 frequently been referred to as "Nutrose". Sodium Caseinate, Difco is a purified 

 product recommended for use in all media in which "Nutrose" or sodium case- 

 inate has been employed. 



EGG ALBUMEN SOLUBLE, DIFCO (B255) 



WHOLE EGG SOLUBLE, DIFCO (B254) 



Egg Albumen Soluble and Whole Egg Soluble are desiccated egg albumen 

 and whole egg, respectively. They are available to bacteriologists who may desire 

 to use such products for the preparation of culture media or for studies of 

 bacterial metabolism. Egg Albumen Soluble and Whole Egg Soluble when 

 rehydrated in 13.5 per cent concentration will give the equivalent of the original 

 form of these products. 



BACTO-RICE POWDER (B146) 



Bacto-Rice Powder was prepared at the suggestion of L. R. Cleveland and 

 is recommended for use in the propagation of Endamoeha histolytica. Cleveland 

 and his co-workers^ »2'^ have given detailed descriptions of the methods they 

 employed for the cultivation of this organism on a medium prepared from 

 Bacto-Liver Infusion Agar with rice powder. Their method is discussed in detail 

 under Bacto-Endamoeba Medium, page 97. Essentially, this procedure is to 

 cover each slant of the medium with fresh horse serum-saline solution and to 

 add sterile rice powder to each tube prior to inoculation with the organism. 

 Bacto-Rice powder is sterilized in a dry heat oven at 160°F. for one hour. 

 Scorching must be prevented. 



1 Arch. Protistenkunde, 70:323:1930. * Am. J. Hyg., 12:606:1930. 



2 Science, 72:149:1930. 



