Ingredients Gms/Ltr :Agar 10.15Peptic digest of animal tissue 8.25Lactose 1.90Sodium sulphite 0.205Ferric chloride 0.0295Monopotassium phosphate 0.0153Erioglaucine 0.0649Basic fuchsin 0.0776Brilliant green 0.0295Oxbile 0.00295* Dehydrated powder, hygroscopic in nature, store in a dry place, in tightly-sealed containers below 25°Cand protect from direct Sunlight.Instructions for Use :Dissolve 20.70gms in 1000ml distilled water. Gently heat to boiling with gentle swirling and dissolve themedium completely. Allow to stand for 5-10 minutes so that the agar hydrates correctly. Sterilize byautoclaving at 15 psi (121°C) for 10 minutes. Cool to 45 - 50°C and pour into sterile Petri plates.Appearance: Blue to purple colour, clear slightly opalescent gelpH at 25°C: 6.9 ± 0.2PrincipleBRILLIANT GREEN BILE AGAR is used for enumeration of coliform bacteria in water and foods. Ituses Basic fuchsin to differentiate between positive lactose-fermenting and lactose-non-fermentingbacteria. The Peptic digest of animal tissue provides the essential nutrients for growth: nitrogen,vitamins, minerals and amino acids. Lactose is the fermentable carbohydrate providing carbon andenergy. Ox bile and Brilliant green inhibit Gram-positive bacteria and most Gram-negative bacteriaexcept Coliforms. Acetaldehyde production by lactose-fermenting organisms, such as E.coli, producecharacteristic red colonies with a pink surrounding area, marked by its reaction with Sodium sulphite inthe presence of Basic fuchsin, a pH indicator. Lactose non-fermenters form colorless, transparent colonies.For the enumeration of coliform bacteria employ sample dilutions, which yield between 10 - 50 coloniesper plate using the pour plate method. Therefore, several dilutions should be made in the meltedmedium, poured and once gelled, incubated at 35 ± 2°C for 18 - 24 hours. The coliform colonies have anintensely red center zone surrounded by a pink halo sharply outlined against the uniformly bluebackground of the medium. Salmonella spp. which do not ferment Lactose, produce colorless to pale pinkcolonies. The medium is sensitive to light, which reduces its effectiveness and changes its color fromstrong blue to purple or pink. The medium should be prepared immediately before use and, if necessary,stored in the dark for as little time as possible.