Hemolysis

Blood agar (5% SB)

Alpha media

Blood agar (5% SB)

Beta media

RBCs and hemoglobin

Alpha substrate

RBCs and hemoglobin

Beta substrate

Blood agar (5% SB)

Gamma media

RBCs and hemoglobin

Gamma substrate

hemolysis, partial digestion of hemoglobin

Alpha results

hemolysis, complete digestion of hemoglobin

Beta results

no hemolysis

Gamma results

Alpha’s + appearance

green/brown zone around/beneath organisms

Beta’s + appearance

clear zone around organisms

Gamma’s + appearance

no clearing around organisms

Strep. pnuemoniae, E. faecalis, Staph. epidermis

Alpha’s + organisms

Strep. pyogenes, E. faecium, Staph. aureus

Beta’s + organisms

optochin

Alpha-hemolytic Strep differentiated by __ sensitivity

bacitracin

Beta- hemolytic Strep differentiated by __ sensitivity