274 DIFGO MANUAL 



and found to be free from demonstrable organisms. It is not guaranteed, how- 

 ever, to be free from filterable forms of viruses. 



Bacto-Ascitic Fluid is used as an enrichment for culture media. The usual 

 proportion for use is one 10 ml. ampul of Bacto-Ascitic Fluid for each 20 or 30 

 ml. of sterile medium. To prevent coagulation of the ascitic fluid, the medium 

 should be cooled to 45-50 °G. before the enrichment is added. Agar media 

 should be prepared with concentrations of agar sufficiently high to allow for 

 dilution of the media with the fluid. In order to prevent contamination, great 

 care should always be taken to observe aseptic precautions when Bacto-Ascitic 

 Fluid is added to culture media. The enriched media should always be incubated 

 to insure their sterility before they are used. 



Bacto-Ascitic Fluid is supplied in packages of one-half dozen or one dozen 

 ampuls of 10 ml. each. 



BAGTO-DUBOS MEDIUM SERUM (B292) 



Bacto-Dubos Medium Serum is filter sterilized fresh beef serum to which is 

 added 7.5 per cent Bacto-Dextrose. Bacto-Dubos Medium Serum is prepared 

 for use in the preparation of a liquid medium for the rapid cultivation of 

 Mycobacterium tuberculosis as discussed on page 108 and 105 under Bacto-TB 

 Broth Base and Bacto-Dubos Broth Base. Bacto-Dubos Medium Serum is sup- 

 plied in packages of one-half dozen and one dozen tubes of 20 ml. each. 



BAGTO-DUBOS MEDIUM ALBUMIN (B309) 



Bacto-Dubos Medium Albumin is a filter sterilized 5 per cent solution of 

 albumin fraction V from bovine plasma in normal saline and contains 7.5 per 

 cent Bacto-Dextrose. Bacto-Dubos Medium Albumin is prepared especially for 

 use in the preparation of a liquid medium for the rapid cultivation of Myco- 

 bacterium tuberculosis, giving readily dispersible growth as discussed on page 

 108 and 105 under Bacto-TB Broth Base and Bacto-Dubos Broth Base. Bacto- 

 Dubos Medium Albumin is a filter sterilized solution supplied in packages of 

 one-half dozen and one dozen tubes of 20 ml. each. 



BAGTO-DUBOS OLEIG SERUM GOMPLEX (B376) 



Bacto-Dubos Oleic Serum Complex is a sterile liquid enrichment for use 

 with Bacto-Dubos Oleic Agar Base for the preparation of a medium for the 

 isolation and cultivation of Mycobacterium tuberculosis. This enrichment is 

 similar to Bacto-Dubos Oleic Albumin Complex, prepared according to the 

 directions given by Dubos and Middlebrook,i except that normal beef serum 

 is used instead of albumin fraction V. 



The complete medium is prepared by adding 20 ml. of Bacto-Dubos Oleic 

 Serum Complex and 5,000 to 10,000 units of penicillin (25 to 50 units per ml. 

 medium) to 180 ml. of sterile rehydrated Bacto-Dubos Oleic Agar Base at 

 50-55 °C. under aseptic conditions. A description of the medium is given on 

 page 107, Bacto-Dubos Oleic Agar Base. The desired concentration of penicillin 

 may be readily obtained by dissolving the contents of one vial of penicillin 

 containing 100,000 units in 10 ml. sterile distilled water. One-half (0.5) ml. 

 (5,000 units) is added to 200 ml. of the sterile medium at 50-55 °C. under aseptic 

 conditions to obtain a concentration of 25 units per ml. medium ( 1 ml. to give 



