Figure 4.

Inhibition by flavonoids (naringenin, quercetin and catechin) of sheep erythrocyte lysis induced by S. aureus NCTC 5655 in PBS, pH 7.4, 37 °C, 60 min. Erythrocytes (1% hematocrit) were preincubated with the flavonoids over 30 min, and then 100 µL of bacteria suspension in PBS buffer (OD₆₀₀ = 2.1) was added. The results represent the average values ± standard deviation, n = 6. Hemolysis induced by S. aureus in the absence of flavonoids was taken as 100 %. *—p < 0.05 compared with erythrocytes in the absence of the flavonoids.