beta hemolysis


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β he·mol·y·sis

complete or "true" hemolysis observed in blood agar cultures of various bacteria, especially hemolytic streptococci and staphylococci; virtually all the erythrocytes are destroyed in a relatively wide, regularly circumscribed, circular zone about the colony, thereby resulting in a clear "halo" of transparent agar; the zone of hemolysis is frequently much wider than the diameter of the colony; the degree of change varies with species of erythrocytes.
References in periodicals archive ?
In our research, two predominant strains (V1 and V2) were isolated from moribund umbo-larvae collected from an episode of mortality at a Yesso scallop hatchery; their potential pathogenicity was hypothesized based on hemolytic activity (including alpha or beta hemolysis) of the isolates on sheep blood agar plates (Schulze et al.
They are nonmotile (except E gallinarum and E casseliflavus), non capsulated organism nonhemolytic usually but sometimes show alpha or beta hemolysis (1,2).
aureus, beta hemolysis and yellowish pigment were spotted in all the plates.
The washed fresh blood agar displayed partial beta hemolysis due to the combination of ATP levels and washing.
Washed expired human blood produces beta hemolysis due to the removal of interferences plus the low ATP level that indicates low red blood cell survival, which means easy hemolysis for the red cells.
pseudoporcinus if it was a catalase-negative, gram-positive coccus; had positive agglutination results with group B PathoDx antiserum; and produced a wide zone of beta hemolysis on the blood agar--in contrast to the zone that is typically (though not always) narrower for GBS.