| In 1980s, Professor of Horticulture of University of the Ryukyus in Japan invented a new compound microorganism product effective microorganisms EM. Since that, compound microorganisms have been used all in the world inclusive of more sixty countries besides China, and economic, society and ecology have gained great profits from that. Mixed cultures fermentations offer a number of advantages over conventional fermentations using a single pure culture; it allows to obtain higher product yield and growth rate, to utilize cheap and impure substrates, to overcome nutritional limitations in poor agricultural residues, and to increase the protection of the culture against contamination. Cellulase is a system containing three types of enzyme: cellobiohydrolase, endo-beta-1,4-glucanase and beta-glucosidase. Cellulose can be degrade into glucose by their acting together. The main problem of taking good use of cellulose materials is the less hydrolyzing effective of cellulases. In the proceeding , with the collection of the products glucose and cellobiose the expression of cellulases are inhibited , which decreased the co-effective directly. For improving the ratio of cellulose degradation , this article has constructed a consortium of microorganisms used for degrading the cellulose with special crystal structure of rice chaff. In the consortium, one is that the compose of cellulase system was adjusted by altering the ratio of some microorganisms, for another, the feedback was decreased by consuming the end product of with some microorganisms. Research and Results1,Some microorganisms with the similar growth conditions were chosen to co-ferment the rice chaff according to the characteristics of cellulase system and their mechanism. In terms of the completion of cellulase and lower activity of beta-glucosidase, Trichoderma reeseiAS3.3711 was used to ferment rice chaff companied with Aspergillus niger3.316 which has a higher activity of beta-glucosidase. Because Saccharomyces cerevisiaeAS2.399, Candida utilis1817 and Lactobacillus delbrueckii all take use glucose as their growth materials, in the latter experiences, one of them was chosen to add to the former two microorganisms for free of the product feedback repression.2,For managing the optimal fermentation conditions of single pure strain, Trichoderma reeseiAS3.3711 and Aspergillus niger3.316 were used for single pure fermentation rice chaff, respectively. Then the followed datum would be referenced inthe subsequent cofermentation: 2% NaOH used for pretreated rice chaff, the pretreatment temperature of 50℃(kept for 24h), fermentation pH of 5.0-5.5 and 100% moisture of fermentation content. 3,From the experient determining the optimal strain added into Trichoderma reeseiAS3.3711 and Aspergillus niger3.316 for avoiding feedback repression, it showed that Saccharomyces cerevisiaes AS2.399 was the most responsive of FPA and ratio of cellulose degradation to mixed culturing in Saccharomyces cerevisiaes AS2.399, Candida utilis1817 and Lactobacillus delbrueckii when Trichoderma reesei 3711 and Aspergillus niger 3.316 were the cooperating partners, and Lactobacillus delbrueckii had the worst results on FPA and ratio of cellulose degradation. And the highest FPA happened at 7th while the ratio of cellulose degradation had no change after 9 days. At last the consortium was composed of Trichoderma reeseiAS3.3711, Aspergillus niger3.316 and Saccharomyces cerevisiaeAS2.399.4,According to the fermentation conditions of single pure culture above and the requirement of fermentation, a orthogonal experiment of ten factors was designed and done. Ten optimal conditions were derived from that. Those were that temperature of pretreatment rice chaff was 30℃; The concentration of NaOH was 3%; Fermentation temperature was 30℃; Fermentation pH was 4.5; The moisture of content was 80%; Trichoderma reeseiAS3.3711 and Aspergillus niger3.316 were inoculated into fermentation media at the 1st day while Saccharomyces cerevisiaes AS2.399 was added into it after fermentat...
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