Orange peel breakthrough in biofuels

Orange peels and newspapers may be the source of a clean, cheap fuel according to scientists from the University of Central Florida who have developed a groundbreaking technique to turn rubbish into ethanol. The technique uses plant-derived enzyme cocktails to breakdown waste materials into sugars which can then be fermented into ethanol which could be a turning point where vehicles could use this fuel as the norm for protecting air and environment for future generations.

The researcher believes that 200 million gallons of ethanol could be made from the discarded orange peels in Florida alone. The process can be applied to several non-food products such as sugarcane, switchgrass and straw. Depending on the waste product, a specific combination of more than 10 enzymes is needed to change to biomass into sugars. All the enzymes used by the researchers are naturally occurring, created by a range of microbial species including bacteria and fungi. The team also cloned genes from wood-rotting fungi or bacteria and produced enzymes in tobacco plants, which when compared to synthetic manufacture reduces the cost by a thousand times, thus reducing the cost of producing ethanol. The food scraps and other waste could also be used to fuel aircraft in the future and British Airways is planning a specialist plant in London to produce biojet fuel, which has to be certified by UK authorities.

 Microbes reprogrammed to ooze oil for renewable biofuel

Using genetic engineering, researcher coaxed photosynthetic microbes to secrete oil bypassing energy and cost barriers that hampered green biofuel production. The real costs involved in any biofuel production are harvesting the fuel precursors and turning them into fuel by releasing their precious cargo outside the cell, thus optimizing bacterial metabolic engineering to develop a truly green route to biofuel production. Photosynthetic microbes like cyanobacteria offer attractive advantages over the use of plants like corn or switchgrass, producing many times the energy yield with energy input from the sun and without the necessity of taking arable cropland out of production.

Researchers are applying their expertises in the development of bacterial-based vaccines to genetically optimize cyanobacteria for biofuel production and they were able to modify these microbes, priming them to self-destruct and release their lipid contents. However, the energy-rich fatty acids were extracted without killing the cells in the process. Rather than destroying the cyanobacteria, the group has ingeniously reengineered their genetics, producing mutant strains that continuously secrete fatty acids through their cell walls. The cyanobacteria essentially act like tiny biofuel production facilities.

If cyanobacteria could be coaxed into overproducing fatty acids, their accumulation within the cells would eventually cause these fatty acids to leak out through the cell membrane, through the process of diffusion. To accomplish this, a specific enzyme, known as thioesterase, is introduced into cyanobacteria.

Scientists look to tobacco as a potential biofuel

Researchers say an age-old cash crop long the focus of public health debate could be used to help solve the nation's energy crisis, by genetically modifying the tobacco leaf for use as a biofuel. The golden leaf is the latest in a series of possible biofuels like switchgrass and algae that are being floated. Scientists believe using tobacco would be beneficial because it would not affect a major U.S. food source, unlike other biofuels made from corn, soybeans and other crops. There are also no worries here about second-hand smoke for commuters stuck in traffic: the tobacco wouldn't be burned to power vehicles, merely used to extract its oils and sugars. Tobacco is an attractive "energy plant" because it can generate a large amount of oil and sugar more efficiently than other crops.

Recently tobacco farms have been hit hard in recent years and this may be an opportunity for some of those tobacco farmers. There are other crops that can be used and the idea of tobacco is that it's not a food crop and farmers are positive and like to grow tobacco in fields that are not being used right now. The tobacco production has dropped about 1.5 percent worldwide over the past 10 years and production has decreased by nearly 39 percent in the U.S. during that same period in part due to the federal buyout program that provided an incentive for tobacco farmers to switch to other crops. 

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