Production of Cellulases by Solid State Fermentation with Three Strains Mixed

In the solid culture media consisted of rice straw powder and wheat bran,the cellulases production by solid state fermentation with White rot fungi NS75,Aspergillus Niger NS83 and Saccharomyces cerevisiae SP5 three strains mixing have been investigated.The results showed that the activities of cellulases produced reached the peak value at the seventh day of fermentation process,in which the yeast Saccharomyces cerevisiae SP5 was inoculated while the White rot fungi NS75 and Aspergillus Niger NS83 had grown 2 days in the solid culture media.The β-glucosidase(β-G) and carboxymethyl cellulase(CMCase) activities produced by three strains mixed fermentation have increased 143.3% and 68.2%,respectively,than that produced by two strains mixed fermentation.The single factor and orthogonal experiment results revealed that,under the optimum fermentation conditions: dosage ratio of rice straw powder and bran powder 8∶2,feed-water ratio 1∶2,inoculation volume ratio of White-rot fungi NS75,Aspergillus niger NS83 and Saccharomyces cerevisiae SP5 1∶2∶1.5(v/v/v),30 ℃ culture 7d,the β-G and CMCase activities produced reached 62305U/g and 30241U/g,respectively.