Blood Agar Base Nalidixic Acid
Blood Agar Base w/ Nalidixic Acid is recommended for differentiation of haemolytic activity of Streptococci.It is a highly nutritive medium. Microorganisms producing haemolysin give visible haemolytic zones on this medium. Blood Agar Base is modified with addition of Nalidixic acid which acts as an inhibitor for the accompanying flora and to support the growth of Staphylococci, haemolytic Streptococci and Enterococci when supplemented with 5% blood. Nalidixic acid blocks the DNA replication of susceptible bacteria and acts against many Gram-negative bacteria.