Cotton enzymatic degradation

The natural fibers of cotton and wood are the most important commercial sources of cellulose. Thus, knowledge of their structure is essential to any discussion of its enzymatic degradation. Several excellent reviews of cellulose structure have been published recently those on cotton by Hamby (22) and Warwicker et al. (76), and on wood in the volumes edited by Zimmerman (79) and C6t6 (7), as well as the discussions of the ultrastructure of plant Cell walls by Miihlethaler (47) and Rollins (59) make more than a general summary here unnecessary. 

Fig.3 shows that under water stress, the enzymatic degradation of MGDG and PC increases, specially when water potentials fall down beyond -1,3 to -1,5 MPa. This increase is undoubtly responsible of the decrease in Cotton... 

Cellulose is the most abundant polysaccharide on Earth, with several thousand D-glucose units in a polymer chain (Figure 21.6). It is the main structural component of the cell wall of green plants. Cotton contains almost 90% of cellulose, whereas wood and dried hemp contain 50% and 45%, respectively. The first cellulose-based thermoplastic polymer was manufactured in 1870 and the first chemical synthesis was done by Kobayashi and Shoda in 1992 [130]. Solubility of cellulose in water depends on its chain length and it is degradable by enzymatic reaction [131]. Cellulose is easy to machine to form various shapes such as textiles, microsphere, sponges, and membranes. 

El-Hafid L, Pham Thi AT, Zuily-Fodil Y, Vieira da Silva J. Enzymatic breakdown of polar lipids in cotton leaves under stress degradation of monogalactosyl-diacylglycerol. Plant Physiol Biochem 1989 27 495-502. 

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