Fig. 8

Cytoplasmic membrane integrity of yeast strains under phenolic acids stress. a relative electric conductivity; b leakage of intracellular 260 nm-absorbing substances; c PI stained cells rate; PS represents the parental strain cells; Control was the control group of adapted strain, which obtained from sequentially transferring and culturing yeast parental strain cells in synthetic medium without phenolic acid at the same condition with Method I; E, I and K were adapted strains from Method E, I and K, respectively. All above yeast strains were treated in PBS (0.1 M, pH = 7.4) with phenolic acids mixture at inhibitory concentration of IC75 at 30 °C for desired time before above detections. Van, Hba and Mix represented vanillic acid, p-hydroxybenzoic acid and phenolic acids mixture, respectively