Biological pretreatment of modified wheat straw for ethanol produ | 52532
Journal of Fundamentals of Renewable Energy and Applications

Journal of Fundamentals of Renewable Energy and Applications
Open Access

ISSN: 2090-4541

+44 1300 500008

Biological pretreatment of modified wheat straw for ethanol production

International Congress and Expo on Biofuels & Bioenergy

August 25- 27, 2015 Valencia, Spain

Nattha Pensupa and Chenyu Du

Posters-Accepted Abstracts: J Fundam Renewable Energy Appl

Abstract :

Wheat straw is the most abundant lignocellulosic residues in UK. And it has been identified as a cheap and effective raw material
for bioethanol production. However at this moment based on current technology, lignocellulosic bioethanol production
process is not ready to be commercialised due to the cost of enzyme required and high energy needed in pretreatment process. The
University of Nottingham has investigated a number of pretreatment strategies and developed a process, which can be applied with
wheat straw. Biological pretreatment is one of pretreatment methods that have been studied. In this study, biological pretreatment of
wheat straw using Aspergillus niger was performed based on solid state fermentation strategy to convert wheat straw to fermentable
hydrolysate. A. niger was cultured on the wheat straw firstly for the cellulolytic enzyme production and then the enzymes were used to
hydrolyse the wheat straw. In a biological pretreatment using autoclaved wheat straw, an enzyme activity of 9.5 FPU/g was achieved.
When 0.5% yeast extract and mineral solution were added, the enzyme activities increased to 24.0 FPU/g after 5 days of cultivation.
While using an alkali modified wheat straw (1% NaOH at 121°C for 30 minutes), the enzyme activity reached 17.2 FPU/g at the first
day of culture. Surprisingly an alkali soaked wheat straw (1% NaOH at room temperature for overnight) led to even higher enzyme
activity (23.3 FPU/g) just after 1 day of culture. Biological pretreated wheat straw was characterized by X-ray diffraction analysis and
the effectiveness of pretreatment was evaluated by enzymatic hydrolysis and fermentation. It was found that biological pretreatment
by A. niger has altered wheat straw structure by decreasing crystallinity region in biomass. Therefore during hydrolysis of biological
pretreated wheat straw, glucose yield has reached 73.26% which much higher than non-treated wheat straw. The hydrolysate was
applied to fermentation process to produce ethanol. The ethanol yield from hydrolysate reached 82.13%.It can be conclude that
biological pretreatment by A. niger is a potential method of pretreat wheat straw for ethanol production.