DEHYDRATED CULTURE MEDIA 95 



Since best results are obtained with solid media having a moist surface, Brain 

 Veal Agar should be used the same day it is prepared or, if not used at once, the 

 medium should be melted and allowed to re-solidify. A moist surface is particu- 

 larly important for the cultivation of the gonococcus, and for that reason it is 

 recommended that sterile rubber stoppers be substituted for the cotton plugs as 

 soon as the slants have cooled. 



One pound of Bacto-Brain Veal Agar will make 8.5 liters of medium. 



ij. Am. Med. Assoc, 86:684:1926. * J. Am. Med. Assoc, 110:1095:1938. 



2 Rev. Med. Malaga, Nov. 6, 1930. ^ Zentr. Bakt., I Abt., Orig., 118:216:1930. 



3Rinascenza Medica, i4:No. 17:1936, XIII. « Am. J. Clin. Path., 3:379:1933. 



BACTO 



POTATO INFUSION AGAR (B51) 



DEHYDRATED 



Potatoes, Infusion from 250 g. 



Bacto-Beef Extract 5 g. 



Proteose Peptone, Difco 10 g. 



Sodium Chloride 5 g. 



Bacto-Dextrose 10 g. 



Bacto-Agar 15 g. 



Bacto-Potato Infusion Agar is prepared according to the formula used by 

 Stockman and MacFadyean for the isolation of Brucella abortus. This medium 

 permits a luxuriant growth of characteristic colonies of B. abortus from infected 

 materials and may be used with excellent results in mass cultivation of the 

 organism in the preparation of vaccines and antigens. Bacto-Tryptose Agar, 

 which does not contain an infusion, as discussed on page 111, is recommended as 

 being far more satisfactory than Bacto-Potato Infusion Agar for the isolation and 

 cultivation of the Brucella. 



To rehydrate the medium suspend 49 grams of Bacto-Potato Infusion Agar 

 in 1000 ml. of a 2 per cent solution of glycerol in distilled water and heat to 

 boiling to dissolve the medium completely. Distribute in tubes or flasks and 

 sterilize in the autoclave for 15 minutes at 15 pounds pressure (121°G.). The 

 final medium will have a reaction of pH 6.8 and will contain a slight precipitate 

 which settles rapidly. The presence of this precipitate in no way interferes with 

 the use of the medium. 



Best results are obtained on freshly prepared media with a moist surface. It 

 is suggested if the medium is not used the day it is prepared that the agar be 

 melted and allowed to re-solidify in order to provide most satisfactory condi- 

 tions for growth. 



One pound of Bacto-Potato Infusion Agar will make 6 liters of medium. 



BACTO 



BORDET GENGOU AGAR BASE (B48) 



DEHYDRATED 



Potatoes, Infusion from 125 g. 



Sodium Chloride 5.5 g. 



Bacto-Agar 20 g. 



Bacto-Bordet Gengou Agar Base, enriched with 15 to 20 per cent blood, is rec- 

 ommended for use in the "cough plate" method for the detection and isolation of 



