Biofuels were all the rage in the 1990s.   Sustainable, activists said, because they refused to do math.   It was only when Republicans mandated and subsidized biofuels in 2005 that environmentalists realized there must be something very wrong with them and $10 billion per year of wasted tax dollars on fuels actually worse for the environment than oil are what we have.

If biofuels can make oil companies look good, imagine what they can do for something like tobacco.

Researchers from the Biotechnology Foundation Laboratories at Thomas Jefferson University say they have identified a way to increase the oil in tobacco plant leaves, which may be the next step in using the plants for biofuel, according to a paper in Plant Biotechnology Journal. 

Vyacheslav Andrianov, Ph.D., assistant professor of Cancer Biology at Jefferson Medical College of Thomas Jefferson University, says tobacco can generate biofuel more efficiently than other agricultural crops but most of the oil is typically found in the seeds – tobacco seeds are composed of about 40 percent oil per dry weight. 

Although the seed oil has been tested for use as fuel for diesel engines, tobacco plants yield a modest amount of seeds, at only about 600 kg of seeds per acre. Andrianov and his colleagues sought to find ways to engineer tobacco plants so that their leaves expressed the oil. 

"Tobacco is very attractive as a biofuel because the idea is to use plants that aren't used in food production,"  Andrianov said. "We have found ways to genetically engineer the plants so that their leaves express more oil. In some instances, the modified plants produced 20-fold more oil in the leaves."

Typical tobacco plant leaves contain 1.7 percent to 4 percent of oil per dry weight. The plants were engineered to overexpress one of two genes: the diacyglycerol acytransferase (DGAT) gene or the LEAFY COTYLEDON 2 (LEC2) gene. The DGAT gene modification led to about 5.8 percent of oil per dry weight in the leaves, which about two-fold the amount of oil produced normally. The LEC2 gene modification led to 6.8 percent of oil per dry weight.

"Based on these data, tobacco represents an attractive and promising 'energy plant' platform, and could also serve as a model for the utilization of other high-biomass plants for biofuel production," Dr. Andrianov said.