| Cellulose as the most abundant organic substance on the earth, is of most widely origins, has already been a type of reborn significant resources and energy. The special structure of the cellulose molecule, along with the particularity of the existence state of a majority of cellulose materials (exist in the form of wood) in nature, makes this precious resources too difficult to make good use of. The resources of plant fiber are abundant in our country, but most of them can't be used by us. Additionally, a quite great part of them are still abandoned by incineration and bring the resulting serious pollution of the environment.The results of many studies show that the degradation and making use of cellulose by biotechnology has its unique advantages. In order to degrade and transform the cellulose to small molecules or other nutrient materials, the key problem is to screen and separate the preponderant strains. In this study, by using cellulose congo-red culture medium and filter paper culture medium, we get the original screening results. by using the rate of cellulose-enzyme reaction, we get the final screening results. By such repeating screening, we get four strains from the samples which are from the spots where the waste cellulose have been placed for many years. They are A1,A8,B4,C2.Generally speaking, the microorganism hydrolyzes and makes use of the cellulose mainly through the enzyme-actuating reaction, which occurs between the cell-external enzyme and the cellulose. In this paper, we studied the extracting condition of cell-external enzyme of A1and C2 and the enzyme-actuating reaction conditions. The studying results show that the solution of sodium chloride at the concentration of 2% can be used as the extracting liquid, and the suitable volume rateof solid-fermentation and extracting liquid isl : 15. The enzyme of the strain Al has the highest activity at pH5.5, the strain C2 at pH5.0. The optimum temperature for the enzyme-actuating reaction is at 50°C, and the most favorable time is 30 minutes. A large scale of stirring is not required. The effects of metal ions to the enzyme-actuating reaction are obvious. The results show that, at proper concentration, Fe2+, Mg2, Zn2, Mn2+ will stimulate the enzyme-actuating reaction, especially the Mg2+ and Zn2+ have the evident effects. However, Cu2+ has a very obvious restraint on the reaction.The production of enzyme by microorganism needs some kinds of inducing factors. In our experiment, we studied the various culture conditions for A8 strain. The results showed: pH6 is the optimal fermenting condition; the optimal fermenting temperature is 35°C; the optimal harvesting period of enzyme is 3~4d; in our experiment condition, the best carbon source is the wheat-stalk powder; the best nitrogen source is(NEL4)2SO4; adding some other carbon source can improve enzyme activity obviously; adding some surfactants can also improve enzyme activity obviously; the most suitable component proportion of culture medium: the rate of solid fermenting stuff to water is 1:3, N/C is 1:15, P/C is by 1:90, the pH is 6. Among them the rate of N/C shows the predominant effect, the ratio of solid fermenting stuff to water takes second place, the initial pH value is the third, The ratio of P/C upon the A8 germ in producing enzyme is lattermost.
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