Figure 1

Morphological features of  Y. lipolytica  NCIM 3589 cells. Control cells (A and B); after treatment with rhamnolipid (C, D); SDS (E, F); and CTAB (G, H) at sub-MIC and MIC concentrations, respectively, for 1 h. The sub-MIC and MIC concentrations of 2.5% and 5% w/v respectively for rhamnolipid and CTAB and 0.3% and 0.62% w/v concentration of SDS were used. Bar indicates 10 μm. The upper panel indicates sub-MIC concentrations and lower panel shows MIC concentrations of the surfactants tested. White arrow shows non-permeability of methylene blue within the yeast cells whereas the black arrow depicts increase in cell permeability and uptake of the dye after treatment with surfactants.