Biofuels

Question 1

What are biofuels?

Answer 1

These are a renewable liquid or gaseous fuel made by and/or from living organisms or the waste that they produce.

Question 2

What % and directive of transport fuel to be made from renewable energy sources?

Answer 2

10% by 2020l EC Renewable Energy Directive 2009

Question 3

What is Bioethanol produced from?

Answer 3

Sugar beet, sugar kane and corn.

Fermentation of soluble sugars by the yeast Saccharomyces Cerevisiae.

Question 4

What is Biodiesel produced from?

Answer 4

From the extraction of the oil from crops such as soybean, oilseed rape and oil palm followed by chemical esterification.

Question 5

What enzyme in the yeast converts sucrose to glucose and fructose ?

Answer 5

intertase.

Question 6

How many ATP molecules does yeast produce in glycolysis.

Answer 6

2 ATP for each glucose - leads to an increase in biomass.

Question 7

What is the function behind the bioengineering of yeast to allow for a reduction in ATP yield?

Answer 7

High ATP - Increase in biomass (waste in carbon and energy resources could have been used towards ethanol)
DIVERT metabolic flux into ethanol not ACETATE.

Question 8

Give an example of a microorganism used in Bioethanol production:

Answer 8

Zymomonas Mobilis - anaerobic, GN

Breaks down bacteria via Entner Dourdoroff

Question 9

What is wanted in the production of Bioethanol?

Answer 9

A reduction in ATP, this is why Z.mobilis is used 2 pyruvates + 1 ATP for each glucose molecule.
Z.mobilis can withstand higher ethanol levels then S.cere

Question 10

What is a limiting factor associated with using Z.mobilis for Bioethanol production?

Answer 10

It can only use a few simple sugars for ethanol production - limit it.

Question 11

Can E.coli be used to produce Bioethanol?

Answer 11

Not naturally, but through bioengineering it can developed to produce fatty acid ethyl esters for Biodiesel.

Question 12

What genetic engineering is needed alongside S.Cerevisiae to convert glucose to ethanol (Bioethanol)?

Answer 12

Needed to convert into ethanol not oxaloacetate or acetate.

Question 13

What is used in the production of Biodiesal?

Answer 13

Fatty acid methyl and ethyl esters.

Question 14

What types of microorganisms can be used in the microbial production of biodiesel?

Answer 14

Yeasts such as S.Cerevisiae and some algae can accumulate fatty acids such as triglycerides, cannot be used directly as fuels. (can be engineered to divert lipid synthesis)
E.coli (can be engineered to produce fatty acid ethyl esters)

Question 15

Which algae produces glycerol, a potential feedstock?

Answer 15

Dunaliella.

Question 16

What is an example of first gen biofuels?

Answer 16

These are made from edible crops.

Question 17

What are examples of 2nd and 3rd gen biofuels?

Answer 17

These are produced from non-food crops or plant waste.

Question 18

What is plant biomass composed of?

Answer 18

Cellulose, hemicellulose and lignincellulose

Question 19

Which plant biomass type makes up the the majority of the biomass in the world?

Answer 19

Lignincellulose.

Question 20

How is plant cellulosic material broken down into 5- and 6- carbon sugars?

Answer 20

Physical and chemical pretreatment.

Enzyme exposure from biomass-degrading organisms (cellulase)

Question 21

Where are microbes that naturally produce cellulase from?

Answer 21

Volcanic soil, termite guts and cow stomachs.

Question 22

What are the current goals for the future of Biofuels?

Answer 22

• Scale up production of microbial cellulases.
• Engineering yeast for higher ethanol tolerance.
• Gen modify m/o to use more sugars and ferment more efficiently
• Get microbial strains to make products such as biobutanol
• Algae ; Biodiesel Production