抽象的

Antifungul Mechanism of Active Substances Produced by Lactobacillus Against Yeast

Zhongjun Chen, Jing Liu, Haixuan Li, Xiaoting Li, Heng Cai, and Yuanqi Wei

At present, some research work has been done on the antibacterial substances produced by lactic acid bacteria, but its antibacterial mechanism is not yet fully understood. The objective of this study was to investigate the inhibiting mechanism of lactic acid bacteria on yeast. Two strains of Lactobacillus ALAC-3 and ALAC-4 being of strong antiyeast ability were studied in the research. Taking Candida albicans as the indicator strain, the inhibiting mechanism was explained by determining the effect of the crude extract of active material on the growth curve, membrane permeability, protein expression and interaction with DNA of yeast. The results were showed that inhibitive substance produced by two strains had the influence on the growth of yeast, the logarithmic growth period was shortened and biomass was decreased. The electrical conductivity, soluble protein content and soluble total sugar content in the culture media of yeast were found to increase after treated by inhibiting substances. It indicated that integrity of yeast cell membrane was changed, so all of these were oozed out from yeast cell. The influence on protein expression of yeast was also detected through SDS-PAGE. Some protein expressing bands of yeast appeared deficient or decreased after treatment by inhibiting substance. Ultraviolet spectroscopic techniques showed that antiyeast substance acted on yeast DNA through the electrostatic binding and groove binding.