Studies On Cellulose Degradation Of Wheat Straw With Aspergillus Niger ZM-8 And Producing Protein Fodder

Biological degradation of wheat straw to produce protein fodder have been studied in this paper. studied in this paper. The purpose of the research is to broaden feedstuff source and raise its quality by biologically transforming and utilizing recycled resources. The ultimate objects of this work are to promote agriculture development continuously as a kind of clean industry. At first, mutant strains Aspergillus niger ZM-8 with high activity of cellulase and Saccharomyces cerevisiae YB-6 with strong growth ability of producing protein fodder were screened from their parent strains of A. niger by treatment of space conditions, and then the conditions for production cellulase of Aspergillus niger ZM-8 was discussed and the conditions of mix-strains wheat stalk solid fermentation to produce protein fodder was explored ,and the wheat stalk solid fermentation technology was suggested. All of these may be summarized as follows:1. Optimal constitution and conditions of wheat stalk solid fermentation to produce cellulase were studied. The results suggested that: the optimum fermentation medium contained 80% wheat stalk powder, 20% wheat bran, a solid: liquid of 1:2, 1.4%nitrogenous amount, nitrogen source was (NH4)2SO4, , and the optimum condition was at the initial pH6.5, 4% inoculum ,28℃,for 96h. Under the optimized medium and fermentation condition, the activities of FPU,CMC andβ-gluase respectively reached 6.75U/g,22.38U/g,21.74U/g.It is increased respectively by 3.0 times,2.2 times,2.3 times than unoptimized .2. The mix-strain wheat stalk solid fermentation of ZM-8 strain and YB-6 strain had been studied, and a best kind of mix-strains ferment system had been optimized out. It showed that the ZM-8 was 4% inoculated first, and the YB-6 was 10% inoculated after three days of the ferment to proceed the mix-strain solid ferment for 48h.Under the best process condition, the cellulose and hemicellulose's content of the solid ferment product had respectively fallen from 42.67% and 32.51% to 32.06% and 23.05%, the degradation rate is 31.38% and 28.51% repectively. The gross protein content is 13.75%.,it is increased by 11 percentage points compared to protein content of wheat stalk, it is increased by 5 percentage points compared to the product that fermented only by the ZM-8 strain .