Tailoring enzymes for biofuel production with reference to Australian biomass

Manufacture of biofuels from existing biomass may provide a sustainable alternative to the extensive utilization of fossil fuels. Biomass offers environmental advantage over fossil fuels as it is a renewable energy source with low sulphur and nitrogen content and is carbon neutral over its production and utilization. Ranges of biomass are reported worldwide to be suitable raw material for bioethanol production. These can be generally classified into three groups; sucrose based (sugar cane), starch based (corn, wheat and barley) and lignocellulosic (which is mostly comprised of lignin, cellulose and hemicelluloses in grasses, wood and straw) materials. However, the limited supply of two biomass groups (sucrose and starch) will not satisfy society’s growing energy demands; thus biofuel technology based on lignocelluloses is under intense investigation. The main bottleneck in lignocellulosic biomass conversion for biofuel production is the enzymatic depolymerisation of cell wall polysaccharides into fermentable sugars. Protein engineering has recently been used to improve the performance of lignocelluloses degrading enzymes, as well as proteins involved in biofuel synthesis pathways. We have produced a recombinant enzyme that has the ability to produce monomeric sugars from a complex substrate. This presentation will summarize current efforts to develop an enzymatic treatment which would facilitate the economical processing of biomass available in Australia for bioenergy generation.

Effects of mucor mucedo on corncob decomposition in pyr-contaminated soil remediation

The effect of polycyclic aromatic hydrocarbon and highly effective degradation fungi Mucor mucedo (MU) was studied on corncob decomposition in Pyr-contaminated soil for 120 days to identify the impact of a degradable immobilized carrier on the remediation of soil contaminated by persistent organic pollutants. Results showed that the corncob was mainly composed of hemicelluloses, cellulose, and water dissolved (WD) material, which accounted for 85 percent of its total weight. MU addition significantly affected corncob decomposition. Thus, humic acid production and WD and benzene-ethanol dissolved material degradation increased. The peaking of the WD content was delayed for 30 days or more. The extractable pyrene content positively correlated with the WD content in the corncob during the decomposition. These results theoretically support a refined remediation principle of immobilized microorganisms.