Characterization of the cellulose-binding ability of geotrichum sp. M111 cells and its application to dehydration of the distilled waste of sweet potato shouchu

Abstract

The cellulose-binding ability of Geotrichum sp. M111 cells was investigated by the micro-tube method which gives an indication of the binding ability of M111 cells. The optimum pH value and temperature were 3-7 and below 50°C, respectively, from measurement of the aggregation height for a mixture of cellulose powder and Mill cells. The binding constant of 0.3% for M111 cells to cellulose powder was obtained in a 20 mM citrate buffer of pH 5.0 at 30°C. Aggregation was inhibited by such surfactants as sodium dodecylsulfate. The binding ability of M111 cells to cellulose fiber disappeared after a treatment with Driselase or Pronase E. This suggests that the binding ability might be related to the cell surface proteins. The dehydration rate of the distilled waste of sweet potato shouchu was accelerated by the addition of M111 cells. The analysis of dehydration by a linear viscoelastic model suggests that the acceleration effect might have been due to the space increase between cellulose fibers with the cell addition.