biofuels conference

1. increasing ethanol productivity from xylose in recombinant Sacharomyces cervevisiae by protein engineering 

 This is what i got from the first lecture in the conference. The presentation was in replace of the original abstract. what i got from this presentation was that they tested  microorganisms in the presence of furfural. E.coli strains were genetically modified to maximize the breakdown of hexose and pentose. Furfural resistant strains were cross resistant to hydroxyl methyl furfural (HMF).EmFR17 and EmFR9 strains helped the microbes grow better on furfural than the LY180 strain. Furfural reductuase YghD,and DkgA gene reduced the HMF strain that increased furfural tolerance. The conclusion from this experiment was that  VghD & DkgA were able to reduce furfural & HMF. Reduced YghD expression increased tolerance to furfural and HMF. The expression of YghD & DkgA from the YghD promoter was aldehyde inducible. 

2. A novel, cost – effective method for producing ethanol from CO2 in hybrid algae

Algenol is a private industrial biotechnology founded in 2006 by Woods, Legere, and Smith. The company is in a developing stage. The process the company uses to produce ethanol from CO2 is by using hybrid algae. The algae is grown in salt water to reserve fresh water. Ethanol is collected as water ethanol condensates and then dehydrated. The algae is grown in closed photobioreactors because all the ethanol produced will go into the atmosphere when it s not enclosed. They are like plastic bags that enclose the algae. Sea water, CO2 and nutrients are introduced. The sun comes out and heats up the bioreactors and ethanol is exposed and escapes into vapor space. When the temperature drops the heat transfers across the surface and condensation occurs. It runs down and then is collected by gravity. Ethanol water is enriched in ethanol and bout 2 to 3x of ethanol is produced. When the industrial CO2 supply is introduced into the photobioreactors the oxygen is removed. As the ethanol condensates it drops down and is collected. Intermediate beer has ethanol concentration that can be used industrially tot hen produce bioethanol. The hybrid algae require 1 gallon of freshwater for a gallon of ethanol production. The key target for this company is to produce 6,000-10,000 gallons/acre/year and to reduce 80% of net GHF emission. The DOE project is to build a pilot- scale integrated biorefinery and use 2 tons of CO2 or more per day. The 3 step process starts with stage 1: Development, planning preparation ( at right now) stage 2: build and facility and stage 3: optimize operation. The reason why this ethanol producing process is cost effective is because CO2 is used as a feedstock, biorefineries are built on desert or marginal land ( food crops can grow in). IT also uses sea water and cheap nutrients and food is not used as feedstock.

3. Emerging standards and policy for biofuels: implication for sustainable environment. 

The World Wildlife Fund (WWF) representative talked from an international point of view. Also in how biofuels was effecting different parts of the world. The standards in common in search for biofuels sources should obey the law, maintain or improve soil quality, protect and improve freshwater resources, and high conservation value areas are not permitted to be converted to feed stock production. The standards that don’t have in common are that only BSI, ISCC and RSB are red complaint for GHG savings. There not all metric based( BSI are only) and not all deal with indirect land use change. The challenges to land use and certification is accounting, traceability, certification, claims and labeling, meeting regulation, and credible auditing process. The WWF are in search of tracking GHG emission, land use for biofuels, and the impact biofuels have on the ecosystem and wildlife. 

4. Fundamental Knowledge for sustainable cellulosic biofuels (Great Lakes Bioenergy)

1. Knowledge to improve plants for use as cellulosic biofuels feedstock; knowledge to improve pretreatments & enzymes in order to generate low- cost cellulosic sugar stream. The issue is that it’s hard to generate fuels from cell wall sugar. An approach to this is by dissecting xylan polymers synthesis by transcript profiling of xylose or mannose-rich seedings ( all cellulose is enriches with mannose and xylose). Then sequence several RNA est to identify candidate genes. Then test the function by inactivating candidate gene. Another issue is that it doesn’t store other energy polymers. oils are the most energy rich form of natural carbon. The use of oil is not required in fermentation. Vegetative cells will alter transcription factor accumulator oil. E. coli and Sacchromyces cerevisiae were 1st grown aerobically to get all the energy and secrete extracellular enzymes to polish sugar streams. Then take away the oxygen and allow the microbes to produce sugar transportation and enzyme. when looking at the chromosome of E. coli you can see it’s covered with proteins and in other areas there are loops where  genes that are highly aerobically induced (high expression of synthesis process). The issues were to track energy input and plant / microbial outputs than different cropping system. Also to measure soil, carbon, water and GHG emission and quantify pest, disease and the ecosystem. 

5. Biomass supply & logistics: A Tennessee perspective 

Biorefinery 2010 is running on corn stock as feedstock but by the end of this year they are aiming to switch to switchgrass. Switchgrass can grow in wet & dry and good and bad soil. They want switchgrass to go dormant to allow some nutrients to get back in. As long as the plants stay dormant the more you lose moister. Alamo switchgrass has the highest yield in Tennessee and grow up to 9 to 10 feet tall. their goal is to make 6000+ acres of swtichgrass. in 2008 they planted 720 acres. there are differences in switchgrass and sometimes the land needs to be tilled due to some land conditions. Swtichgrass reach 3 years of growing season. The issues are harvesting, feedstock quality, risk management (fire), transportation and storage ( very importnat to keep the switchgrass dry in storage).

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