The Effects of Ethanol on Cell Growth and Cell Characteristics of Arthrobacter Simplex TCCC 11037

In this paper,effect of ethanol volume fraction on cell growth and cell characteristics of Arthrobacter simplex TCCC 11037 were studied.The results showed that cell biomass and specific growth rate declined and the lag phase prolonged with ethanol volume fraction increased.When 6%(volume fraction) ethanol were added,the measurable cell growth could not be clearly observed.On the other hand,cell shapes considerably changed as ethanol volume fraction gradually increased.The cell integrity was broken down and plenty of cytoplasm was released at 8% ethanol addition.In addition,it was found that the cell utilization of glucose decreased with the ethanol volume fraction increased,After 32 h incubation,the residual glucose concentrations of control volume fraction and 3% ethanol addition reduced from 9.8 g·L-1 to 2.2 g·L-1 and 5.6 g·L-1,respectively,while no glucose consumption was remarkably detected at 6% ethanol addition.The membrane potential and membrane permeability of cell were further analyzed by Rh123 method and FDA method,respectively.The results showed that membrane potential reduced while membrane permeability enhanced with ethanol volume fraction increasing.At 3% and 6% ethanol addition,the membrane potential decreased 14.14% and 24.58% while the membrane permeability increased 6.58% and 18.37%,respectively.