Phenylethyl Alcohol Agar Medium for Isolation of Anaerobic Bacteria

Abstract

SUMMARY:About seventy strains of strict anaerobes (Peptococcus, Peptostreptococcus, Bacteroides, Sphaerophorus, Fusobacterium, anaerobic Corynebacterium and Eubacterium) were found to grow relatively well on Phenylethyl Alcohol (PEA) agar containing 5 % pepsin-digested cattle blood. However, half of strains of Veillonella and two-thirds of strains of Clostridium showed no or poor growth.Mixed cultures of aerobes and anaerobes were inoculated onto PEA agar to find how effective this medium was in selective isolation of anaerobes. A few clinical cases in which PEA agar was used are presented.The data presented in this paper confirmed and extended the results shown in a brief report of Dowell, Hill and Altemeier (1964) in which only a small number of anaerobes were examined.Their recommendation that PEA agar should be used routinely for isolation of anaerobes in clinical materials was approved. Some precautions in handling and the limitations of this medium are discussed.