Identification And Functional Studies Of A Cellulose-Decomposing Fungus

Cellulose is the main component in plant cell wall, and the most abundant biomass in the world. Biodegradation of cellulose has long been studied all over the world with lots of progresses, however, the efficiency of biodegradation is still not high enough for industrial application due to the highly ordered structure within the cellulose chains, which prevents the accessibility of enzymes and results in the recalcitrant property of cellulose.An aerobic cellulose-degrading fungus was isolated from soil source and identified and designated as Arthrobotrys sp. CX1. When cultured on the filter paper double plate, CX1 could degrade filter paper with a phenomenon of the paper becoming transparent like being water-melted. CX1 does not secret extrocellular cellulases, and there is no reducing sugar to be detected when cultured in the liquid medium, which comes to the conclusion that the mechanism of cellulose-degradation of CX1 is quite different from that of most known aerobic fungi.After treated with CX1, the microstructure of filter paper fibers were changed, with the decrease of crystallinity, the emergence of cavities between microfibrils and the swell of microfibrils. Both the hydration degree and the saccharification ability of filter paper were significantly increased. Therefore, CX1 could disrupt the hydrogen bond of inter- and/or intra-cellulose chains leading to the amorphism of the crystalline cellulose.