Environmental Engineering Reference
In-Depth Information
70
Pordesimo '05
Masoero '06
Unpublished
60
50
40
30
20
10
0
Stalk
Leaf
Cob
Maize stover part
FIGure 16.7
Components of maize stover. Unpublished data were obtained from a number of hybrids of
Pioneer Hi-Bred Intl., Inc. (A DuPont Company) grown in Woodland, CA in 2007 and 2008.
50
Cellulose
Hemicellulose
Lignin
Ash
45
40
35
30
25
20
15
10
5
0
Maize
Wheat
Rice
SwitchgrassMiscanthus
Crop
FIGure 16.8
Chemical composition of vegetative dry matter from various grasses. (Data from Wiselogel
et al.,
Bioresour Technol
, 56, 103-109, 1996; Christian et al.,
Bioresour Technol
, 83, 115-124, 2002;
Lewandowski et al.,
Agron J
, 95, 1274-1280, 2003a; Lewandowski et al.,
Biomass Bioenergy
, 25, 335-361,
2003b; Velasquez et al.,
Wood Sci Technol
, 37, 269-278, 2003; Sun et al.,
J Agri Food Chem
, 53, 860-870,
2005; DOE (U.S. Department of Energy), Biomass feedstock composition and property database, Department
of Energy, Biomass Program, http://www.eere.energy.gov/biomass/progs/search1.cgi, 2006; Mani et al.,
Biomass Bioenergy
, 30, 648-654, 2006; Hongzhang, C., and Liying, L.,
Bioresour Technol
, 98, 666-676,
2007; Garcia-Barneto et al.,
Bioresour Technol,
100, 3963-3973, 2009.)
16.4.1 c
ElluloSE
S
ynthESiS
Cellulose, a major constituent of cell walls, is a paracrystalline form of H-bonded β-1,4-glucan
chains and is deposited directly into the apoplast by the plasma membrane-localized cellulose
synthase complex. A major breakthrough in our understanding of the biosynthesis of cell wall
polysaccharides was the identification of cellulose synthase catalytic subunit (
CesA
). The gene for