Himedia Hugh Leifson Glucose Medium

Hugh Leifson Glucose Medium is recommended for the differentiation of Staphylococci from Micrococci on the basis of their ability to ferment glucose anaerobically. This medium is prepared as described by FDA, it contains high salt concentration and is thus used for the identification of pathogenic and halophilic organisms and for testing aerobic and anaerobic breakdown of glucose by Staphylococci and Micrococci for differentiation of Staphylococci from Micrococci. The medium contains a high concentration of carbohydrate and low concentration of peptic digest of animal tissue to avoid the possibility of an aerobic organism utilizing peptic digest of animal tissue and producing an alkaline condition which would neutralize slight acidity produced by an oxidative organism. Oxidative organisms produce acid in unsealed tube with little or no growth and no acid formation in sealed tube while fermentative organisms produce acid in both sealed and unsealed tubes. If acid is produced, it is indicated by change in colour from purple to yellow throughout the medium.