Fig. 11. (A) The viability of S. cerevisiae upon incubation at pH 5.5 with different amounts of BRB-loaded shellac NPs coated with ODTAB at room temperature at different incubation time. The solutions were prepared from 0.05 wt% BRB (shellac) NPs stock solution coated with 0.05 wt% ODTAB. (B) The yeast cells viability upon incubation with 0.001 wt% BRB–NPs, 0.001 wt% free BRB, 0.005 wt% shellac NPs coated with 0.001 wt% ODTAB, 0.001 wt% BRB–(shellac NPs) coated with 0.001 wt% ODTAB, and 0.001 wt% pure ODTAB. (C) SEM images of the control sample of S. cerevisiae, (D)–(H) SEM images of S. cerevisiae incubated with 0.01 wt% BRB loaded in shellac NPs coated with 0.01 wt% ODTAB after 2 hours at room temperature.