Inhibitory mechanism of Forsythia suspensa biological preservative on Alternaria alternata after harvest of winter jujube
To explore the antibacterial activity and mechanism of Forsythia suspensa biological preservative against Alternaria ziziphi,the minimum inhibitory concentration(MIC)and minimum bactericidal concentration(MBC)were determined by in vitro antibacterial test.At the same time,combined with the effects of Forsythia biological preservative on the release of cell components,cell membrane per-meability,intracellular enzyme activity,and mycelium morphology of Alternaria,the bacteriostatic mechanism of Forsythia biological pre-servative on Alternaria was further clarified.Results showed that the MIC and MBC of Forsythia suspensa biological preservative against Al-ternaria alternata were 25 mg/L and 100 mg/L respectively.After being treated with 100 mg/L Forsythia biological preservative,the cell membrane permeability of Alternaria alternata was enhanced,resulting in a significant increase in the contents of nucleic acid,soluble protein and malondialdehyde(MDA),and the relative conductivity.It not only inhibited the activities of Na+/K+-ATPase and glutathione reductase(GR)of Alternaria alternata,reduced their activities by 0.58 times and 1.8 times respectively,but also significantly reduced ergosterol content and respiratory inhibition rate.To sum up,Forsythia suspensa biological preservative has a good antibacterial effect on Alternaria alternata,which can be achieved by destroying the cell membrane structure of Alternaria alternata,changing the membrane per-meability and interfering with energy metabolism.
万方数据
维普
