48 Introduction to Renewable Biomaterials
His choice of terminology,diastase, led to the tradition of using the suffix -asein
biochemistry for the naming of enzymes. In 1834, Payen began the systematic study
of wood from which he discovered a substance from the plant cell walls that could be
hydrolyzed (broken down with water) to glucose units (similar to starch). He called the
substance “cellulose,” which began another tradition of using “-ose” as the suffix to name
carbohydrates. In 1835, he departed from industrial work in favor of a professorship of
industrial and agricultural chemistry at the École Centrale des Arts et Manufactures. In
1839, he then accepted a joint appointment at the nearby Conservatoire des Arts, which
he held in conjunction with his original appointment until his death in 1871. He was a
prolific researcher, publishing over 200 papers and 10 books on topics such as dextrans,
sugars, lignin, cellulose, and starch. His seminal paper on cellulose and lignin isolation
was published in 1838. These experiments in 1838 revealed that in addition to cellulose,
wood contained an oxidizable crusty substance that was later designated as “lignin” in
1857 by Schulze. Payen treated the wood with a concentrated nitric acid solution and
later washed the residue with an alkaline solution (sodium hydroxide) to dissolve the
crusty substance. Payen noted significant differences between the wood and the crusty
substance; he is also credited with the first Klason lignin isolation method whereby
he used concentrated sulfuric acid to remove the polysaccharides, which then allowed
for the isolation of the “lignin” fraction. Today, the American Chemical Society (ACS)
honors Anselme Payen’s memory by awarding each year a prize in his name to the
scientist who in the opinion of the Cellulose and Renewable Materials Division (CELL)
of the ACS has contributed the most to the science, engineering, and technology of
cellulose and renewable materials (more information can be found at the ACS site:
http://cell.sites.acs.org/anselmepayenaward.htm).
2.3 Chemical Reactivity of Cellulose, Heteropolysaccharides, and Lignin
A proper understanding of the chemical, biological, and mechanical reactivity of the
biopolymers in biomass is crucial to determining the best approaches for their strategic
utilization. Throughout history, a basic understanding of lignocellulosics has lagged
behind their usage on a societal level. This is not surprising because pragmatism
dictates that this should be the case; people will always be practical in approaching
the usage of materials before a fundamental survey of the properties of the materials is
accomplished. However, advances in bio-fuels and biomaterials cannot be made from
a pragmatic perspective because there are too many technical hurdles to overcome
and, additionally, the economic barriers to implementation are severe. Therefore, this
section attempts to survey the individual reactivities of the biopolymers under scrutiny.
The survey examines several different stressors or reactants used on the biopolymers
and their responses.
2.3.1 Cellulose Reactivity
One of the complicating factors in the proper understanding of the reactivity of cellulose
is its accessibility in addition to its chemical makeup. It is organized elegantly within a
lignocellulosic matrix that consists of its interplay with the heteropolysaccharides and
