90 DIFCOMANUAL 



Bacto-PPLO Agar is a base used in preparing a solid medium for the isolation 

 and cultivation of pleuropneumonia-like organisms (PPLO), as described by 

 Morton, Smith and Leberman.^ These authors found that Bacto-Peptone, Bacto- 

 Tryptose and Bacto-Yeast Extract were satisfactory peptones in a medium for 

 the cultivation of these organisms. Bacto-Peptone in the presence of an infusion 

 of Bacto-Beef Heart for Infusions gave best results. Bacto-PPLO Agar duplicates 

 their recommended formula. 



Bacto-PPLO Agar, enriched with Bacto-Ascitic Fluid or Bacto-PPLO Serum 

 Fraction will permit the development of colonies of PPLO visible microscopi- 

 cally, after 48 hours or longer aerobic incubation at 37°C. After 48 hours incuba- 

 tion inverted plates are examined under the low power of the microscope, 

 focusing through the medium to its surface for the presence of surface colonies 

 on the medium. Cultures should be examined daily after 48 hours for a period of 

 one week before the plate is considered negative. PPLO colonies are round with 

 a dense center and a less dense periphery, giving the appearance of a fried egg. 

 They vary from 10 to 500 microns in diameter (0.01-0.5 mm.) and grow into the 

 medium. Individual organisms are not resolved, so there is little evidence at this 

 magnification of any cellular organization. Vacuoles are seen in the periphery of 

 some of the colonies. They are the large bodies characteristic of the pleuropneu- 

 monia group. 



To rehydrate the medium, suspend 34 grams of Bacto-PPLO Agar in 1000 ml. 

 of cold distilled water and heat to boiling to dissolve the medium completely. 

 Distribute in flasks and sterilize in the autoclave for 15 minutes at 15 pounds pres- 

 sure (121°C.). After the medium has been cooled to 45-60° C, add 1 per cent 

 Bacto-PPLO Serum Fraction or 25 per cent Bacto-Ascitic Fluid. Mix thoroughly 

 and pour into sterile petri dishes. The reaction of the unenriched medium will 

 be pH 7.8. 



One pound of Bacto-PPLO Agar will make 13.3 liters unenriched medium. 



1 Am. J. Syphilis Gonorrh. Venereal Diseases, 35:361 :i95i- 



BACTO 



BRAIN HEART INFUSION AGAR (B418) 



DEHYDRATED 



Calf Brains, Infusion from 200 g. 



Beef Heart, Infusion from 250 g. 



Proteose Peptone, Difco 10 g. 



Bacto-Dextrose 2 g. 



Sodium Chloride 5 g. 



Disodium Phosphate 2.5 g. 



Bacto-Agar 15 g. 



Bacto-Brain Heart Infusion Agar is recommended as a solid medium for the 

 cultivation of fastidious pathogenic bacteria and fungi. A selective medium for 

 fungi may be prepared by adding penicillin and streptomycin to the sterile 

 medium. 



The liquid medium, Bacto-Brain Heart Infusion, has for many years been 

 the medium of choice for the cultivation of streptococci, pneumococci, meningo- 

 cocci and many other organisms considered difficult to cultivate, and has been 

 especially valuable in blood culture work. This medium, solidified with agar to 

 give Bacto-Brain Heart Infusion Agar, is a satisfactory solid medium for the 

 cultivation of these organisms. In addition, the solid medium has been especially 

 valuable as a neutral or slightly alkaline medium for the cultivation of patho- 

 genic fungi. Selective media for fungi may be prepared by adding antibiotics or 



