The Research On Using Wood Flour Hydrolysate As Carbon Source To Produce Bacterial Cellulos

Bacterial cellulose belongs to the special product of basal metabolism and is a kind of protective coating, whereas the plant cellulose (PC) plays a structural role.This paper selected the acetobacter xylinum bred in the lab as the experimental strains, explored the fermentation conditions of using poplar wood flour hydrolysate as the carbon source to produce bacterial cellulose.Use air drying poplar as the raw materials, and grind poplar into wood flour after the ball-milling treatment.Use the mixed enzyme combining cellulose and hemicellulose to dispose wood flour.In the experiment, use reaction temperature, reaction time, used enzyme concentration and PH value of the reaction as the variables to explore the best condition of enzyme hydrolyzing the wood flour.And then use enzyme to hydrolyze the wood flour under the best conditions, measure the reducing sugar content produced from reaction by DNS method, and calculate the hydrolysis rate.And the enzymatic hydrolysate will be used as the carbon source to be added into the culture medium after it has been disposed.It should be cultivated for fermentation for several days under the untouched state, and then bacterial cellulose can be produced.Finally, do the performance measurement for the produced bacterial cellulose.Poplar wood flour needs to have ball-milling pretreatment, and when enzyme concentration is 30mg/ml the temperature is 50℃, pH value is 6 and the time is 5 hours, there is maximum absorbancy at the place of 540nm, after calculation, enzymatic hydrolysis degree is 38%.If the glucose content of poplar wood flour hydrolysate account for 30% of that of the total medium, the wood flour is 18g/L, take which for reference, when the glucose content is 14g/L, the maximum bacterial cellulose can be cultivated. The best cultivation conditions for the bacterial cellulose produced by static cultivation fermentation of acetobacter xylinum is that the inoculum age of the seed solution is 36h, the cultivation temperature is 30℃, and the inoculum size is 6%, the incubation period is controlled at 6d, and the initial pH value is 6.0.The fibrous membranes produced by using poplar wood flour hydrolysate as the carbon source to produce bacterial cellulose is characterized by using infrared spectroscopy and the scanning electron microscopy (sem) spectra, analyze its morphological structure and confirm it as the bacterial cellulose.It suggests that the enzymatic hydrolysate of poplar saw dust can be used as carbon source to produce bacterial cellulose, and by comparing the structure observed by scanning electron microscope and peak of wave measured by infrared spectroscopy, the structure of the produced bacterial cellulose hasn’t been changed.