BUFFERED CHARCOAL YEAST EXTRACT AGAR BASE

Feeley et al originally formulated Charcoal Yeast Extract (CYE) Agar. This medium was a modification of the existing F-G Agar. F-G Agar had starch and casein enzymic hydrolysate as ingredients in the composition. Feely et al replaced these two with charcoal and yeast extract respectively, and reported better recovery of Legionella pneumophilla. Later Paseulle reported that supplementation of the Charcoal Yeast Agar with ACES buffer improved the performance of the medium. Edelstein further modified the medium by adding alpha-ketoglutarate. This addition helped in improving the sensitivity of the medium. Buffered Charcoal Yeast Extract Agar Base is based on Edelsteins Modification.
Legionella species are non-spore forming, narrow, gram-negative rods. Legionella causes pneumonia (Legionnaires disease) or a milk, febrile disease (Pontiac fever). They do not oxidize or ferment carbohydrates in conventional media or grow on sheep blood agar. Growth is much better and more rapid on Buffered Charcoal Yeast Extract Agar. Amino acids are the major sources of energy for Legionella. The amino acid L-cystine holds an absolute requirement as it plays major role in growth metabolism of Legionella. This amino acid as well as ferric pyrophosphate helps for the growth of Legionella.
For selective isolation, antibiotic supplements can be used to suppress contaminating microorganisms. Legionella Selective Supplement II (CCVC) containing cephalothin, colistin, vancomycin and cycloheximide or Legionella Selective Supplement IV (MWY) containing glycine, polymyxin B, anisomycin, vancomycin, bromothymol blue and bromocresol purple are often used. Wear gown, mask and gloves while handling Legionella cultures. Work in a safety hood.

for selective isolation and cultivation of Legionella species