Research On Liquid Fermentation Optimization Of Lentinula Edodes And Antibacterial Activity Of Lentinin

Lentinin,isolated from Lentinula edodes,has demonstrated broad application prospect for its unique activities such as antibacterial,antioxidant activity,inhibition of tumor growth,reduction of blood lipid,immunomodulation.With the progress of liquid fermentation technology,more fungi had cultured with the method of liquid fermentation.Liquid fermentation is not affected by time,and had continuous production,short cycle,high production efficiency.It may for industrialized production.This paper focuses on studying the liquid fermentation process optimization and optimization of the extraction process of polysaccharide and its antibacterial activity.The main findings are as follows:(1)On the basis of single factor test and orthogonal design optimization,this paper researched the effect of speeds,temperature,culture time,liquid volume and other conditions on liquid fermentation.From the study,the optimum conditions for liquid fermentation:The cultivation conditions were optimized as temperature as 26?,250mL shake bottled liquid volume 130mL,speed 150 rpm respectively.(2)On the basis of single factor experiment,the orthogonal experiment and the response surface optimization design,to study the effects of water extraction and alcohol precipitation extraction temperature extraction of Lentinula edodes,solid-liquid ratio,extraction time,extraction times,the establishment of a total of polysaccharide Multiple factors affect quadratic regression equation,and so determine the AAP's optimum extraction conditions were:extraction temperature 50?,extraction time 2.5 h,1:45 for the ratio of solid to liquid,extracted 2 times.(3)Lentinin showed highly effective antibacterial activities against.Staphylococcus aureus(S.aureus).LIVE/DEAD experiment,to verify and investigate antibacterial efficiency of lentinin on S.aureus.Moreover,there are large quantities of living cells and few dead cells in the images(low concentration of lentinin treated).However,in experiments,a high concentration lentinin yielded the completely opposite result.Mechanisms of cell integrity study through change of cell membrane,wall and enzyme by SEM experiments.Through morphological changes in S.aureus,mechanisms are examined for bacterial damage caused by lentinin.