Standard Nutrient Agar is formulated as per the recommendation of APHA as a general purpose medium for the cultivation of non-fastidious organisms from water and wastewater, dairy and food products (1, 2).
Peptic digest of lean meat provides the amino acids and large chain peptides. Beef extract (meat infusion) provides water soluble substances like carbohydrates, vitamins, organic nitrogen compounds and salts (3). Sodium chloride maintains osmotic equilibrium.
Directions: Suspend 45 grams in 1000 ml distilled water. Heat to boiling to dissolve the medium completely. Sterilize by autoclaving at 15 lbs pressure (121°C) for 15 minutes. Mix well before pouring in sterile Petri plates.