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More Plastics From Plants

If you’ve ever walked up to a potted plant, thinking it was real, and then discovered it was – gasp – made of plastic, then you’ve seen the kind of plant that Metabolix researchers dream about.

Recently, Metabolix published a paper describing their latest plant trials and efforts to get plants to, if not actually be entirely made of plastic, grow an industrially useful quantity of polymer inside their cells. In the trial, which used tobacco plants, the researchers upped the level of polyhydroxyalkanoate (PHA)* in research crop tobacco to levels of up to 9% of the total dry plant weight. PHA levels of up to 17% were found in leaf tissue. The company figures its engineered tobacco plants produce 10 times more PHA bioplastic than in previously published reports.

Photo:Dale Callaham, Central Microscopy Facility, University of Massachusetts in Amherst

The result is probably better described, though, by the photo of a tobacco plant cell chock full of polymer blobs. One has to wonder what the upper limit would be for the percentage of polymer in a plant before it turns into the species more commonly found in the back of a greasy diner.

*Two bits of additional information: Metabolix says PHAs ”have a broad range of industrial applications as performance, biodegradable bioplastics and as renewable starting materials for the production of a number of existing specialty and commodity chemicals. As polymers, PHA bioplastics offer excellent performance in use and have the unique ability to biodegrade in a wide range of environments including compost, soil, wetlands, marine and anaerobic digestion facilities.”

And C&EN visited Metabolix last summer, you can read about it here.

Codexis Puts Enzyme to Work for Clean(er) Coal

This week in Washington, DC, energy luminaries associated with the ARPA-E program are gathering to talk about clean energy technologies and present a progress report on what the program’s grants have made possible.

coal-fired power plant

Enzymes to clean coal? Credit: U.S. Department of Energy

Biocatalyst firm Codexis has helpfully offered a preview of its update on a research project aiming to cut down on the downsides of carbon capture technologies for coal-fired power plants. The so-called “clean coal” technologies can nearly double costs and lower the amount of electricity produced by power plans, the company points out.

Codexis will present data from its ARPA-E sponsored research project that uses modified carbonic anhydrase enzymes to capture carbon dioxide from power plant emissions.  

Carbonic anhydrase enzymes are highly reactive – they exchange carbon dioxide into our lungs when we exhale. The Codexis version functions in the high temperatures and industrial conditions of the flue gas environment. The project has demonstrated enzyme stability in solvents in temperatures up to 75 degrees C. The use of these enzyme-powered solvents could reduce the energy needed for capturing carbon by 30%, says the firm.

Codexis, which went public in April, is best known for its long-term biofuels partnership with Shell. In May, it received a $4.7 million grant from ARPA-E  for development of innovative technology to remove carbon dioxide  from coal-fired power plant emissions.

Bayer MaterialScience, PPG Get Presidential Shout Out

Yesterday, President Obama was at Penn State to press for more federal support of green buildings. In his speech promoting the Better Buildings Initiative, he suggested that many in his audience might not consider green buildings to be “sexy.” But I suspect that chemists have many reasons to find green buildings to be pretty darned appealing.

Bayer makes spray insulation for commercial building roofs. Credit: Bayer MaterialScience

For one thing, green building materials research – like that conducted by a clean energy hub in Philadelphia headed by Penn State - can earn chemical firms a Presidential shout-out. The hub includes corporate partners Bayer Material Science, which is working on new materials for insulation and facades that save energy, and PPG Industries, whose researchers are creating walls that reflect sun and windows that reflect infrared, according to the President’s remarks.

He pointed out that making buildings (and homes) more energy efficient is a green upgrade that comes with no tradeoffs. The whole point of retrofitting (or building green from the start) is to save on energy costs. The roadblock, though, is the initial upfront cost, which is a cash expenditure. The President’s initiative - through tax credits and financing help – is supposed to minimize the up-front sticker shock. He’d like to pay for the cost of the program by rolling back “subsidies to the oil companies,” saying, “it’s time to stop subsidizing yesterday’s energy.”

Syngenta to license gene tech to Agrivida

Agrivida plants.

Agrivida's modified switchgrass. Credit: Agrivida

Biotech start-up Agrivida has announced that it is now in a research alliance with Syngenta Ventures, the venture capital arm of agro-giant Syngenta. C&EN visited Agrivida in the summer to learn a bit about the company’s technology. Agrivida is working to develop versions of energy crops like corn, switchgrass, miscanthus, and sorghum that have enzymes enabling the breakdown of cellulose in the plant, which would decrease ethanol production costs and the need for expensive enzymes.

To keep the plants from turning to mush before harvest, Agrivida is also developing a protein switch called an intein, that would, in the words of company founder Jeremy Johnson, “has the ability to cleave itself out and reconnect the rest of the sequence” of genes that code for the enzyme.

The deal with Syngenta means that Agrivida will have access to crop technology and intellectual property in return for Agrivida equity. Back in the summer, cleantech analysts pointed out that a deal with a major agricultural firm – with access to a huge marketplace of farmers – would be the ideal next step for the firm.

Over the weekend, Agrivida’s scientists presented new experimental data at BIO’s Pacific Rim Summit on Industrial Biotechnology and Bioenergy in Honolulu. The company reported that their engineered crops can reduce production costs by over 30 percent, and would allow ethanol producers to decrease enzyme loadings by over 75 percent, compared to today’s processes.

Finally, Peer-reviewed Research on BPA Levels in U.S. Foods

canned food in grocery store

Canned food was part of a new BPA study. Credit: Melody Voith

It’s always heartening to see facts start to catch up to controversy. My colleague Kellyn Betts reports on a new study in Environmental Science & Technology that analyzed a market basket of food products, including canned food, for traces of Bisphenol A. BPA is used as a plasticizer in some food packaging and to make epoxy resins in food cans, and has come under scrutiny for possible health effects, especially on infants and children.

C&EN has covered activist, government, and tradegroup takes on the BPA controversy, as well as efforts taken by chemical makers and food brands to do away with BPA. Recently, a survey by Green Century Capital Management found that canned food manufacturers were making real progress replacing BPA. That’s why it’s rather surprising to read what is now being called the very first peer-reviewed study to look at how much BPA actually migrates into food sold and consumed in the U.S. This seems like vital data that would be needed to make public policy decisions. One area of controversy, for example, is whether the EPA’s recommended limit for BPA consumption is too high. So it’s helpful to note that the research suggests a U.S. consumer’s possible “body burden” of BPA is below the recommended threshold, but perhaps at or above a threshold where there may be concern.

Cleantech: Patent, Publications, and Money

Two cleantech start-ups recently covered by C&EN have milestones to report. And another is appearing at the ACS Spring National Meeting this week.

Cellulosic ethanol firm Qteros, with technology from the UMass lab of microbiologist Susan Leschine now has a patent on its Q microbe. The microbe can break down the polysaccharides in plant cellulose into simple sugars and then ferment the sugars into ethanol. The company says this is a money and time saver, as it reduces the number of processing steps and eliminates the need for separate enzymes. C&EN recently wrote about Qteros’ new CEO John McCarthy, and his efforts to scale-up the business (subscription required).

And the New York Times DealBook blog has reported that low-carbon cement start-up Calera will get $15 million in funding from Peabody Energy, a coal company. Calera claims to have the ability to bubble CO2 emissions from power plants into high-mineral content groundwater to create a cement-like product. According to the company, the process locks in the CO2 from the power plant and also saves on CO2 emissions that would normally be used to create the cement. You can read about Calera and three other low-CO2 cement firms in C&EN (subscription required).

Out in San Francisco, agricultural biotech firm Agrivida, which is developing specialized non-food crops that can be turned into chemicals and fuels, will be presenting research at the ACS meeting. Agrivida will explain how it has developed a “platform [that] allows for expression of cell wall-hydrolyzing enzymes within a plant’s growing cell wall without the occurrence of detrimental phenotypes that may impact yield.” Basically, like Qteros, the trick is to get a head start on conversion from cellulose by picking the right biological systems. My colleague Sue Morrissey mentioned Agrivida in her story about recent ARPA-E funding awardees.

If any ACS meeting attendees have a chance to see Agrivida’s presentation, I would love to hear from you.

As much as I love San Francisco, I am writing this post from Munich, Germany, where I am preparing to visit Wacker Chemie this week. You’ll hear more about this soon.