Making Cellulose Viable

First generation biofuels are obtained in the easiest manner from the fermentation of starchy foodstuffs, primarily corn or wheat or from sugar such as sugar cane. At this time, only the Unites States and Canada has sufficient land and economic resources to make starch biomass feasible, while Brazil exclusively uses sugar cane. Even so, the cost of biofuels is driven by fluctuations and costs of these sources which can become commercially unviable during times of drought, bad growing weather, crop disease or high demand starch and sugar sources for other uses. This has made the production of 1st generation biofuels uneconomical and applicable only to first-world economies.

In addition, because corn and wheat are also used in various animal and human food chains, extra demand from biofuel production becomes politically unviable and adds commodity price pressures. Therefore, other sources of raw materials must be found that are not foodstuffs, and are cheap and plentiful and not subject to price variations.

Solving the problem with enhanced fermentation

During the Second World War, US Army canvas tents set up in the Philippines and other SE Asian areas were seen to rapidly decompose or rot. This was found to be due to a fungus called T.reesei, which excretes an enzyme called cellulase; the enzyme broke down the cellulose component of the canvas tents into sugar leaving the tents unusable. Subsequently, T.reesei has been studied for its ability to convert cellulose materials such as hay or grass into sugars that could then be fermented to bioethanol. While T.reesei is fairly efficient in breaking down the cellulose to sugar; it is not efficient in the breakdown of sugar to bioethanol and thus the need for a two-step fermentation process.

Cellulose is a main structural component of plants, hay, trees, paper and other related material and has been used as a feedstock to create second-generation biofuels. The issue with cellulose is that it requires a very expensive pre-treatment in order to release the sugars. Thus while the creation of second generation biofuel production has been envisioned, the practical events to scale it up to economical production levels is still unrealized.

PLUSWave offers a way of being able to use cellulose materials in a fermentation process that releases the required sugars while improving the yield. PLUSWave can stimulate cell growth and protein (enzyme) production of both fungi (cellulose to sugars) and yeast (sugars to bioethanol) allowing for consolidation of the current 2-step fermentation process into one with an expected overall efficiency increase of 60%. (see Diagram).

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