Fig. 9

NBT reduction assay by GBS-S19 in the presence of polyols. Glucose or polyols were added to 100 μl of GBS-S19 bacterial suspension and incubated with 0.5 mg/ml of NBT overnight at 37 °C. GBS-S19 incubated with 1% of glucose was used as a positive control. The absorbance A₅₇₀ was expressed as percent of NBT reduction by GBS. 1% of glucose was considered 100% of NBT reduction. Order of tubes for each panel: blank, no polyol, glucose, mannitol, sorbitol, erythritol. Bars represent the average A420 values obtained from three independent experiments compared with the value obtained from (0%) to determine statistical significance; N.S indicates not significant