Of Bacillus Sp. 16a Ramie Degumming Mechanisms Preliminary Study And Its Key Enzyme Purification

Comparing with the chemical degumming technics of boiling with hot alkali solution, biodegumming is more advancing and has a bright application prospect. At present, the technical problem lies in how to further reduce the residual gum: merely increase the key enzyme-pectinase cannot persistently enhance the degumming effect, and there are still arguments about the position that hemicellulase holds in degumming. The purpose of this essay is to discuss whether the latter has a synergetic effect on pectinase.Bacillus sp. 16A, which has high efficiency in the degumming of ramie, was selected from the bacteria reserved in our laboratory. In comparison with other relating reports, the residual gum was blow 14% after treated by this strain, and this process could be finished within 4 hours, with proved its high degumming efficiency.Bacillus sp. 16A was identified as Bacillus subtilis by 16s rDNA sequence comparing method and Biolog Microbial Identification System. Analysis of enzymes in the cell-free culture supernatant revealed that Bacillus subtilis 16A can release high-level polygalacturonase as well as a small amount of hemicellulase, while no cellulose was detected. Thus it wouldn't harm the ramie fibers during the degumming process. So it's an eximious degumming strain of ramie.The cell-free culture supernatant of Bacillus sp. No.16A was treated by acetone into three groups of degumming liquor with different composition of pectinase and β-mannanase. Their degumming effects were investigated by analyzing some of the fibers'characters, including softness, dispersal degree, residual gum, weight lost, fineness and SEM photograph. The results showed that β-mannanase has certain synergetic function on pectinase in ramie degumming; namely, the β-mannanase can improve the degumming effect of pectinase. And this outcome shed light on the...