Antimicrobial Mechanism of Ginkgo biloba Leaf Extracts （GBLE） Against Saprophytic staphylococcus

Abstract:

In order to investigate the antimicrobial mechanism of Ginkgo biloba leaf extracts （GBLE） against specific spoilage bacteria in aquatic products，minimal inhibitory concentration （MIC） of GBLE against Saprophytic staphylococcus was measured by method of broth dilution combined with plate counting in this paper. The impact of GBLE on the growth of bacteria，the permeability of cell membrane and cell wall were also investigated by the methods，such as growth curve，content of alkaline phosphatase （AKP），electrical conductivity and content of protein. The structure of the Saprophytic staphylococcus cells was observed by scanning electron microscope （SEM）. The results showed that the MIC was 100 mg/mL. The inhibitory rates of MIC and 2MIC concentration of GBLE were 60.58% and 81.34% respectively. The growth of bacteria was inhibited and the permeability of cell membrane increased significantly. The result of observation with SEM revealed that the structure of Saprophytic staphylococcus cells were destroyed and the bacteria began to be adhesive with each other. The inhibition effect of GBLE against Saprophytic staphylococcus was related with the damage of cell membrane and cell wall.