摘要
[Objectives]To investigate the antimicrobial activity and mechanism for saponin from Sapindus mukorossi against Escherichia coli.[Methods]E.coli was used as the test bacteria,and the antimicrobial effect of Sapindus saponin was studied by the minimum inhibitory concentration method.The antimicrobial mechanism of Sapindus saponin was studied in terms of growth curves,membrane potential,activity of cells,cell surface morphology and cell internal structure.[Results]The results indicate that Sapindus saponin can inhibit the growth of E.coli,the minimum inhibitory concentration is 5 mg/mL and has a significant inhibitory effect on the growth of E.coli.After treated with Sapindus saponin,the membrane potential of E.coli increased by 16.7,17.3 and 19.1 times after exposition to 0.5,1,2 MIC Sapindus saponin respectively.PI staining results show that cell viability decreased and permeability of cell membranes increased.The results of SEM and TEM further corroborate the membrane damage,the cell was damaged after exposition to Sapindus saponin.[Conclusions]The antimicrobial mechanism of Sapindus saponin were to changed membrane potential of cell,and damage the cell membrane structures.
[Objectives] To investigate the antimicrobial activity and mechanism for saponin from Sapindus mukorossi against Escherichia coli. [Methods] E. coli was used as the test bacteria, and the antimicrobial effect of Sapindus saponin was studied by the minimum inhibitory concentration method. The antimicrobial mechanism of Sapindus saponin was studied in terms of growth curves, membrane potential, activity of cells, cell surface morphology and cell internal structure. [Results] The results indicate that Sapindus saponin can inhibit the growth of E. coli, the minimum inhibitory concentration is 5 mg/mL and has a significant inhibitory effect on the growth of E. coli. After treated with Sapindus saponin, the membrane potential of E. coli increased by 16.7, 17.3 and 19.1 times after exposition to 0.5, 1, 2 MIC Sapindus saponin respectively. PI staining results show that cell viability decreased and permeability of cell membranes increased. The results of SEM and TEM further corroborate the membrane damage, the cell was damaged after exposition to Sapindus saponin. [Conclusions] The antimicrobial mechanism of Sapindus saponin were to changed membrane potential of cell, and damage the cell membrane structures.
