BioFuels Flashcards
What are BioFuels?
Renewable liquid or gaseous fuels made by and/or from living organisms or the waste they produce
what is bioethanol produced from?
sugar beet, sugar cane and corn
how is bioethanol produced?
by fermentation of soluble sugars largely sucrose and glucose from starch by yeast sacch cerevisiae
how is biodiesel produced?
Produced by extraction of oil from soybean, oilseed rape and oil pam followed by chemical esterification
what is biodiesel composed of?
fatty acids methyl and ethyl esters
what enzyme degrades starch in the bioethanol production process?
amylases which produced glucose and other simple sugars that can enter glycolysis
what bacteria are used in the bioethanol production process?
Zymomonas mobilis and saccharomyces cerevisiae
what does Zymomonas mobilis do and what is it?
anaerobic gram neg bacterium breaks down glucose via the entner doudoroff pathway
what does saccharomyces cerevisiae do?
convert glucose to ethanol via glycolysis
what is the advantage of using z. mobilis over s. cerevisiae?
Z mobilis can withstand higher ethanol levels than s cerevisiae
what is the disadvantage of using z. mobilis over s. cerevisiae?
Z mobilis can only use a few simple sugars including glucose, fructose and sucrose for ethanol production which may limit its broader usefulness
how can Saccharomyces cerevisiae be altered to help biodiesel production?
genetically engineered to divert lipid synthesis away from triglycerides and into fatty acid ethyl esters
what do algae produce from sunlight and co2?
biomass including oil which can be converted into biodiesel
how can lignocellulose be used to create biofuels?
Decomposition into simple 5/6 carbon sugars by physical and chemical pretreatment then enzymes from biomass-degrading organisms.
The simple sugars can be converted into fuels by microorganisms
what are some examples of current research into biofuel production?
Scaling up production of microbial cellulases for cellulose conversion into fermentable sugars, discovery of new enzymes
Engineering yeast for higher tolerance to ethanol to increase bioethanol production
Genetically modifying microorganisms to utilize a wider range of sugars and ferment these more efficiently
Optimizing microbial strains to produce alternative products such as biobutanol
Finding algae that produce high yields of oils or that are otherwise suitable for biodiesel production