Monday, September 20, 2010

Cellulosic Starch. - biotechnology challenge.

Cellulosic Starch would be the one technology that would go further to feeding the next three billion people than any other biotechnology. There is as far as I know no work being done on it.
The key is to take the same cellulose breaking enzymes that turn straw into sugar for ethanol production and use them to make food grade glucose most of which would then be made into starch with another enzyme.
We can grow grass, straw and jungle leaves from the high Arctic to the deserts and on to the equator. We can grow much more cellulose than grain in the same field. Planting and harvest is closer together and the crop of grass can be perennial.
The cellular processes that turn glucose into starch is not yet fully understood. We need to identify the key cellular processes in edible plants, publicise the need so private, commercial or charitable funding can be found.
A team needs to be created.
The final desirable product would be a machine sized for a first world farm or third world village that can do the following steps.
  • Pre test the plant matter for toxic contamination. This may include a slow conveyor that allows the plant matter to be visually checked for obvious contamination dirt, plants and animal material. 
  • Mill and break down the cellulose into glucose or sucrose in sterile water through the action of the enzyme.
  • Sterilise or filter out the enzyme. 
  • Filter-out any non digested cellulose, lignite, plant oils and other extraneous non sugars.
  • Possibly, concentrate the sugars recycling the water. 
  • Synthesise edible starch from the sugars. Perhaps using a naked enzyme or an engineered glucose feeding starch cell culture. 
  • Remove the enzyme or plant hormones that make that work. 
  • Dry and package in a storable form. 
  • Test for contaminants, spoiling or other problems. This should be concurrent with each step. 
  • Regenerate waters filters, testing gear, etc.
  • Produce more bulk enzyme and plant hormone or plant starch cell cultures. 
We should ensure that the taste is not influenced much by the taste of the feed stock. A bland flavourless starch is best. Some of the glucose can be retained for sweetening. Some can be used with other value added cell cultures to produce proteins such as gluten, lysine, Guanine, etc. These would need to be carefully labelled since some people can't eat gluten.

If we can make such a technology then we can harvest grasses and other fast growing plants and turn that into starch. Then using a mix of the raw plant material and the starch we can feed livestock for protein: eggs, milk and meat.
Because hay and straw can be stored for months and years; areas with short growing season and long droughts can feed many more people.

Ideally the technology should be cheap enough to sell in the third world. Financing arrangements would be needed for both the research phase, the third world deployment phase and the follow up maintenance phases.

While the starch will compete with normal starch crops it will augment their availability not replace them. As world population grows those industrial applications for bulk starch will switch from food grade starch to cellulosic starch freeing up more edible starch. Food grade cellulosic starch would fend off famine in the developing world. There are ethics questions to be asked and they should be asked early but I can't see how a categorical no would make sense.
It wont solve all humanities problems but it will feed many people.

Up Date: Someone's cracked it.
Brilliant. Percival Zhang and his team managed to do it in a single step enzymatic process.

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