Project Title:

High value products and ethanol from wheat straw and bran: enhancing our understanding and capacity for fungal bioconversion

Funding:

Department of Agriculture, Food and Fisheries - Research Stimulus Fund

Project duration:

December 2007 - Decembery 2011

Project participants:

Teagasc Oak Park

University College Dublin

Project objectives:

The objective of this project is to optimise the capacity of Fusarium oxysporum to convert lignocellulosic straw and bran to ethanol and valuable phenolic by-products. To this end, we will;

• Identify F. oxysporum strains with high capacity to produce ethanol and release valuable phenolics from straw and bran.
• Use two approaches (functional genomics and gene disruption) to determine the enzymatic profile and activity of the most promising strain during growth on straw and bran.
• Clone and characterise (i) genes encoding enzymes involved in ethanol production and phenolic release and (ii) promoters of other genes highly expressed during growth on lignocellulosic materials.
• Manipulate these genes/promoters towards enhancing the ethanol-producing and phenolic-releasing capacity of F. oxysporum.

Research abstract:

Commercial production of alcohol from wheat renders the majority of hemicellulose unutilized, reducing the efficiency and cost-effectiveness of the process. Fusarium oxysporum is a good candidate for the direct and efficient conversion of relatively low-value lignocellulosic materials to ethanol. 

Although fermentation performance by F. oxysporum is somewhat lower than that of other fermenting microorganisms, its ability for simultaneous lignocellulose-residue saccharification and fermentation is considered as a significant advantage. While many studies have analysed the activity of such F. oxysporum enzymes, the concerted activity of hydrolyzing, depolymerising and side-chain-removing enzymes during lignocellulose bioconversion to ethanol has not been elucidated.

We will do so using functional genomics; this technique in parallel to a programme of gene disruption via insertional mutagenesis will identify enzyme-encoding genes of interest and gene promoters of interest to the biofuel industry (i.e. that drive high gene expression during lignocellulose conversion). We will sequence uncharacterised F. oxysporum genes and promoters of interest and use fungal transformation studies to functionally characterise and enhance the activity of genes of interest.

It is intended that this study will enhance the potential of using Fusarium oxysporum and/or its genest o economically produce bioethanol and other added-value products (e.g. ferulic acid) from farm-based renewable materials.

Results:

Upon completion of this project, all datasets will be collated and the research findings submitted for publication in peer reviewed scientific journals. Once the scientific merit of the results has been validated, they will be available for your information on gmoInfo.