Bordet-Gengou Agar with Charcoal 500 grams/bottle

Bordet-Gengou Agar with Charcoal is a selective medium used for the isolation of Bordetella pertussis from clinical specimens. The medium is used in clinical laboratories for the isolation of Bordetella pertussis, the etiologic agent of whooping cough, from nasopharyngeal swabs and other sources of pharyngeal exudate. Bordetella pertussis is a Gram-negative, aerobic coccobacillus capsulate of the genus Bordetella, and the causative agent of pertussis or whooping cough. This medium was developed by as a transport medium for whooping cough specimens, but proved to be useful as an enrichment medium for the selective isolation of B. pertussis and B. parapertussis. It consists of charcoal agar as a basal medium supplemented with cephalexin to inhibit bacteria indigenous to the nasopharynx and defibrinated horse blood to support the growth of Bordetella species. Cephalexin is a cephalosporin antibiotic that inhibits most normal flora of the nasopharynx. Use of the medium without cephalexin in parallel is recommended, since a few stains (<10%) of B. pertussis will not grow on selective plates; also the nonselective medium is used for subcultures to obtain a larger amount of growth for additional testing, such as agglutination or immunofluorescence testing. Beef Extract and Casein Peptone provide nitrogen, vitamins, minerals and amino acids essential for growth. Starch in the medium acts as a growth factor, probably functioning like a colloid protector and neutralizes toxic products that form during the development of the organisms. Sodium chloride supplies essential electrolytes for transport and osmotic balance. Charcoal neutralizes fatty acids that are toxic to microorganisms. Cefalexin is added as a selective agent to partially inhibit normal flora from the respiratory system. Niacin is a vitamin which enforces the growth.