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popsci_2013 02222.txt

#We Could Eat Trees: Scientists Turn Inedible Plant Cellulose Into Starchy Snacksomeday it will be be summer again and it will be time for fresh sweet corn. In the future you might be able to eat the whole thing cob and all. This weird possibility is courtesy of some scientists at Virginia Tech who have transformed cellulose a mostly indigestible polymer into helpful indispensable starch. Plants produce cellulose and starch which are chemically similar for very different purposes. Cellulose forms the cell walls of most plants algae and even some bacteria and we use it for anything from clothing (cotton is almost all cellulose) to paper to ethanol. Starch is a plant's energy source and it's ours too in the form of tasty things like potatoes wheat and corn. The difference between the two is a simple change in the hydrogen bonds that form the molecules. Animals like cows and pigs can digest cellulose thanks to symbiotic bacteria in their digestive tracts but humans can't. It's important in our diets as source of fiber in that it binds together waste in our digestive tracts. Y. H. Percival Zhang an associate professor of biological systems engineering at Virginia Tech set out to make it a food source. Since cellulose and amylose are both glucose chains you would just have to rearrange their hydrogen bonds. This is anything but simple although essentially Zhang and colleagues used chemistry. They worked with a series of synthetic enzymes to break down the hydrogen bonds in some plant material that would not otherwise be used for food like corn cobs and leaves. The enzyme cascade enabled the cellulose molecules to reconfigure into amylose which is a form of starch. A key ingredient in this process a special polypeptide cap is found in potatoes. The resulting product is not exactly the future of bread flour but it can be used as a fiber source or food-safe biodegradable packaging perhaps. The remaining portion of the original material was treated with microbes to produce a form of glucose that can then be used for ethanol. The whole process didn't require any unusual heat or chemical reagents other than the enzymes themselves so it would be easy to reproduce on larger scales Zhang and his colleagues say. Cellulose is the most common carbohydrate--indeed the most common organic material--on the planet so using it for food could be a superb way to feed millions of people they argue. There is an urgent need to use abundant and renewable nonfood agricultural and forest residues and dedicated bioenergy crops that can grow on marginal land and require low inputs they write. The paper appears this week in the Proceedings of the National Academy of Sciences. This ID is obsolete. On Twitter I'm known as Thunderbill2. As for this article it's kind of scary. It's bad enough that the corn is modified mostly genetically into another unknown poison now they want us to eat the cob too and get a bigger dose. I won't buy sweet corn anymore unless it's certified organic. When it gets too scarce and expensive I'll grow my own if I can find pure seed. Whoever they are will find more than just a few of us refusing to eat their poison. The megalomaniacs of the world have their work cut out for them. I wonder what they'll do when nobody is left for them to dominate and bully. Cellulose is already a common ingredient in food. The inedible sawdust helps to help give certain foods consistent texture and a boost to fiber. Just check the nutrition labels. This would be more useful for ethanol production than eating the cob

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