General Differential Media

GENERAL DIFFERENTIAL MEDIA: General Differential Media or Enrichment media are usually liquid media or broth that supports the growth of a particular bacterium while inhibiting the growth of unwanted bacteria. Typical example of an enrichment medium is the Selenite F broth culture medium which is used for the culture of faecal specimens. Selenite F broth inhibit the growth of commensals or non-clinically relevant bacteria in faecal specimens prior to their subculture onto solid culture media plates. Alkaline peptone water is another example of an enrichment medium; and enrichment media are generally used to recover pathogens from faecal samples. Enriched media are culture media that also contain additional growth nutrients (e.g. blood, serum and egg yolk) like enrichment media for the cultivation and isolation of fastidious bacteria but unlike enrichment media, enriched media are mainly solid culture media; and they are generally used to cultivate fastidious bacteria e.g. Streptococcus species and Haemophilus species. Blood agar and chocolate agar are examples of enriched culture media.