K.A.A. CONFIRMATORY AGAR 500 grams/bottle

KAA Confirmatory Agar (Kanamycin, Aesculin, Azide) is a selective medium for the isolation and confirmation of intestinal enteroccoci in foods. KAA Confirmatory Agar is used to confirm positives from KAA Presumptive Broth (Cat. 1209) tubes. Kanamycin, Sodium azide and Sodium citrate have a great inhibitory effect on the accompanying bacterial flora, they inhibit the growth of Gram-positive and Gram-negative bacteria, and the medium is highly selective for esculin-hydrolyzing enterococci. Esculin and Ferric Ammonium citrate are esculin indicators which detect the esculin-hydrolysing bacteria. They hydrolyze the esculin to give glucose and esculetin. These microorganisms present black zones around the colonies from the reaction of the resulting esculetin with the iron ions. Tryptone provides nitrogen, vitamins, minerals and amino acids essential for growth. Yeast extract is a source of vitamins, particularly of the B-group essential for bacterial growth. Sodium chloride supplies essential electrolytes for transport and osmotic balance. Bacteriological agar is the solidifying agent. The presence of intestinal enterococci, is an indicator for faecal contamination, especially when the contamination occurred long ago and the less resistant coliform bacteria, including Escherichia coli, are already dead when the analysis is carried out. Intestinal enterococci grow forming small, translucent colonies surrounded by a black halo. This medium is recommended by CeNAN for food and drinks analysis.