Download Slide 1

Powering the Future: Biofuels
Activity: Bacterial cellulase
• Describe the use of cellulose in paper and sources of
naturally produced cellulases
• Carry out an experiment to investigate the presence
of cellulase producing bacteria in soil
• Assess the pros and cons of the method for
identifying cellulase producing bacteria
Facts and Figures
• To help combat climate change the UK has a target to reduce carbon
emissions by 80% by 2050.
• 30% of the UK renewable energy could come from biomass heat and
electricity by 2020.
• To meet the European Renewable Energy Directive, the UK is aiming for
10% of transport energy to be from renewable sources by 2020.
• 18% of the sustainable renewable road transport fuel used in the UK
between April 2012 and April 2013 came from UK feedstocks.
© University of Dundee at SCRI
Plant Cell Walls: Lignin is a strengthening and waterproofing material
that encrusts the sugar based polymers in plant cell walls making them
hard to access for biofuel production.
© University of Dundee at SCRI
Plant Cell Walls: Woody plants, such as miscanthus and willow, convert much of the
carbon that they capture into lignocellulosic polymers, which are not a readily
fermentable form of carbohydrate.
© University of Dundee at SCRI
Plant Cell Walls: Feedstocks rich in lignocellulose require treatment with acids,
alkalis or steam explosion methods to hydrolyse hemicellulose and break
down lignin, enabling access to the cellulose by enzymes.
Institute of Food Research
Steam explosion unit: We need to optimise the release of sugars from agricultural and woodindustry wastes to produce a fermentable feedstock that microorganisms can use to produce fuels.
Pre-treatment of feedstocks with steam opens up the structures in plant cell walls to enable access
by cellulase enzymes.
© University of Nottingham
To harness the potential of lignocellulosic (plant cell wall) materials, we need to optimise the
release of sugars from agricultural and wood-industry wastes to produce a fermentable
feedstock that microorganisms can use to produce fuels. Developing robust microbial
strains that can use these feedstocks will enable sustainable production of bioethanol.
Professor Katherine Smart
BSBEC LACE Programme
School of Biosciences
University of Nottingham
© University of Nottingham
Industrial biotechnology: Researchers at the University of Nottingham have devised
gene technologies which are now being used to enhance the productivity of bacterial
strains in the large-scale production of chemicals and transport fuels from renewable
plant biomass.
Method
1. Collect soil samples or obtain a sample of Cellulomonas.
2. Label test tubes with contents (soil, paper, control etc), name
and date.
3. Add 5 ml of nutrient broth to the control tube using a pipette,
and seal.
4. Add a soil sample to 30 ml of nutrient broth in a conical flask.
Swirl the flask to form an evenly distributed soil suspension and
then allow the particulate debris to settle for 1-2 minutes.
5. Add 5 ml of the soil suspension to each test tube using a
pipette.
6. Add the paper samples to the tubes and seal the tubes.
7. Incubate the test tubes for about 1 week at room temperature.
Activity: Bacterial cellulase
• Describe the use of cellulose in paper and sources of
naturally produced cellulases
• Carry out an experiment to investigate the presence
of cellulase producing bacteria in soil
• Assess the pros and cons of the method for
identifying cellulase producing bacteria
Contributors