PPLO Agar was described by Morton, Smith and Leberman (1). It was used in a study of the growth requirements of Mycoplasma (2), along with the identification and cultivation of this organism. (3-5). Pivotal information regarding Mycoplasma has been documented by Sabin (6). Hayflick et al have reported the information regarding the cultivation of Mycoplasma (7).
For the cultivation of Mycoplasma the medium ingredients and all the supplements should be free of any toxic substances even in small amounts. Beef heart infusion, peptic digest of animal tissue and peptone provide nitrogen, vitamins, amino acids and carbon in these media. Sodium chloride maintains the osmotic balance of these formulations. Many Mycoplasma require serum for their good growth and also presence of antibiotic is necessary to prevent the growth of contaminating organisms. Mostly the Mycoplasma species are aerobic or facultatively anaerobic but some are microaerophilic. Few are anaerobic saprophytic Mycoplasma which grow best at 22-35°C while pathogenic strains grow at 35°C. Mycoplasma when grow in the agar medium show typical morphology and form colonies below the agar surface and do no grow without serum. Plates or tubes should be incubated in an atmosphere containing 5-10% carbon dioxide and examined after incubation of 48 hours but they should not be discarded as negative until after incubation for 3 weeks.
PPLO colonies are round with a dense center and a less dense periphery, resembling a “fried egg” on PPLO Agar. Vacuoles,large bodies characteristic of Mycoplasma species are seen in the periphery. Colonies vary in diameter from 10 to 500 microns (0.01-0.5 mm) and penetrate into the medium.
Directions: Suspend 36 grams in 700 ml distilled water. Heat to boiling to dissolve the medium completely. Sterilize by autoclaving at 15 lbs pressure (121°C) for 15 minutes. Cool to 45°C and aseptically add 300 ml Horse serum (RM1239) or 10 vials of Mycoplasma Enrichment Supplement (FD075). Mix well before dispensing. 25% Ascitic fluid can be used instead of Horse serum.