Jay Cheng talks with
ScienceWatch.com and answers a few questions about
this month's Emerging Research Front Paper in the field of
Article: Hydrolysis of lignocellulosic materials
for ethanol production: a review
Journal: BIORESOURCE TECHNOL, 83 (1): 1-11 MAY 2002
Addresses: N Carolina State Univ, Dept Biol & Agr Engn,
Raleigh, NC 27695 USA.
N Carolina State Univ, Dept Biol & Agr Engn, Raleigh,
NC 27695 USA.
Our paper provides a comprehensive review of ethanol production from
lignocellulosic materials, including the work that has been done in the
past, the current research status, and future perspectives in this area.
How did you become involved in this research and were
any particular problems encountered along the way?
"One of the big challenges in converting
lignocellulosic materials into ethanol is the high
lignin content that blocks the access of cellulase
enzymes or chemicals to cellulose during
I had worked in ethanol fermentation in the late 1980s and early 1990s. In
the last 10+ years, I have been working on the conversion of organic waste,
specifically swine waste, into bioenergy through anaerobid digestion and
clean-up of the wastewater.
In many swine farms in the South and Southeast, the farmers grow coastal
Bermuda grass as a part of their nutrient management plan for the treatment
of their swine waste. However, some farmers have difficulty selling their
Bermuda grass as a product, which led us to a research project on
conversion of coastal Bermuda grass to fuel ethanol in 1999. We have been
investigating coastal Bermuda grass, switchgrass, and rye straw since then.
Where do you see your research leading in the
One of the big challenges in converting lignocellulosic materials into
ethanol is the high lignin content that blocks the access of cellulase
enzymes or chemicals to cellulose during hydrolysis. Therefore, a
pretreatment is necessary to remove lignin from the materials, prior to
further processing, which is one of the main reasons a lignocellulosic
biomass-to-ethanol technology is too expensive for commercialization.
I am currently working with my colleagues in using genetic transformation
techniques to generate transgenic switchgrass that has much lower lignin.
Hopefully the expensive pretreatment process can be avoided in converting
low-lignin transgenic switchgrass into ethanol.
Do you foresee any social or political implications for
Our research has been focused on converting grasses such as switchgrass and
coastal Bermuda grass into fuel ethanol. Unlike corn, these grasses can
grow on marginal land and do not compete against food and feed production.
Furthermore, these grasses have high yields of dry biomass production, e.g.
switchgrass can produce around 10 metric tons per acre per year.
Their growth does not require extensive fertilization. Commercialization of
grasses-to-ethanol technology would provide a sustainable biofuel
production and reduce our nation's dependency on foreign oil, create jobs
in feedstock farming, ethanol production, and related work, and
significantly reduce carbon dioxide emission which is critical in
preventing the global climate change from worsening.
Jay J. Cheng, Ph.D.
North Carolina State University
Biological & Agricultural Engineering Dept
Raleigh, NC, USA