Fig. 2.

(A) Percent hemolysis caused by peptides. Peptide antibiotics at MIC and 5× MIC (E. coli) were incubated with 0.4% RBCs in PBS. The results are expressed as percent hemolysis. RBCs incubated with 0.1% Triton X-100 were considered to be 100% lysed. Standard deviations from three observations are plotted. (B) Mammalian-cell cytotoxicity (MTT assay) of peptide antibiotics at MIC and 5× MIC (E. coli) against HeLa cell lines. Test samples were incubated with cells for 24 h in RPMI 1640. Untreated cells served as a negative control. The ratio of the OD₅₇₀ for peptide-treated cells to the OD₅₇₀ for untreated cells was used to calculate the percent viability of the cells. Standard deviations from three observations are plotted.