Technique	HEMOLYSIS ,(/,)/,(
Principle	Hemolytic activity is often an important distinguishing feature of many microbes. The two forms of hemolysis, alpha and beta hemolysis are easily observed around surface colonies on blood agar. Alpha hemolyis is characterized by a green z one around the colony. Microscopic obervation shows that the erythrocytes are still intact. Beta hemolysis is indicated by a clear zone around the colony. The clear zone may or may not be colourless. Hemolytic activity is associated with hemolysin(s), many of whichare phospholipases. The type of erythrocyte used in the blood agar may affect the expression of the hemolysin. Thus rabbit erythrocytes are very sensitive to staphylcoccal alpha hemolysin while human erythrocytes are resistant. Staphylcoccal beta hemolysin attacks sheep erythrocytes at 37 C but the degradative effects are not visible until the RBC's are cooled ( the hot cold toxin).
Cautions	Streptolysin O and its relatives are easily oxidized and require a reduced envirnment for their expression.
Method
Results
Positive control
Negative control
Reagents
Reference