Preston Agar Base 500G

Preston Agar Base is recommended for selective isolation of thermotolerant Campylobacter species. This selective medium was described by Bolton and Robertson for isolation of Campylobacter species and is recommended by APHA. Isolation of Campylobacter species on selective agar medium is made both with or without selective broth enrichment. Direct plating without enrichment is adequate for fresh faecal samples, faecal contents or intestinal specimens as high numbers of the organisms may be anticipated. For the food samples enrichment is required. On Preston Agar Base thermotolerant Campylobacter species tend to produce moist, grey, flat spreading growth, which tends to coalesce. Occasionally some contaminating organisms may grow on this medium but they are usually restricted to the area of primary inoculum. These include Pseudomonas species, more resistant coliforms, Streptococcus species and yeasts.