Study On Inhibiting Mechanism Of Antiyeast Substances Produced By Lactobacillus

In the test, two strains of lactobacillus ALAC-3 and ALAC-4 being of strong antiyeast ability were studied. Taking Candida albicans as the indicator strain, the inhibiting mechanism was explained by determining the effect of the active material on the growth curve, membrane permeability, phosphorus metabolism and protein expression of yeast. The results were showed as follows:(1)The best saturation of ammonium sulfate for crude extraction of antiyeast substances was 40%.’(2)Antiyeast substance produced by two strains certain effect on growth curve of yeast. The logarithmic growth period was shortened and biomass was decreased.(3)The electrolytes; soluble protein and soluble total sugar in yeast cell were oozed out after treated by inhibiting substances. It means that penetrability of yeast cell membrane was changed, so the electrical conductivity, soluble protein content and soluble total sugar content of yeast increased. And the active substances come from ALAC-4 had a greater effect on cell membrane of yeast.(4)The antiyeast substance produced by two strains of lactobacillus affected normal phosphorus metabolism in yeast, so as to inhibiting the growth of yeast.(5)The protein expression in yeast was influenced by inhibiting substance coming from two strains. The growth of yeast was inhibited by leading to protein deficiency or decreased. The above results showed that the antiyeast substance produced by lactobacillus had the effect on the growth curve, membrane permeability, phosphorus metabolism and protein expression of yeast. So yeast cannot grow and multiply normally. And the substances coming from ALAC-4 had a stronger inhibiting yeast activity.