Biotech Corn Boosts Bioethanol Productivity

In Iowa, USA, bioethanol producers are recruiting farmers to grow the biotech corn commercially known as Enogen which is designed to produce ethanol more efficiently.

The Swiss company Syngenta developed the Enogen hybrid to offer ethanol producers a chance to improve their efficiency. It was approved for commercial cultivation in the USA in 2011. The proprietary hybrid contains a microbial gene that encodes a thermo-stable alpha amylase enzyme, the primary enzyme used in dry grind corn ethanol production. Directly expressed in the starchy endosperm of the corn kernel, alpha amylase speeds up the breakdown of starch into sugar, the initial step in converting grain into ethanol. According to Syngenta, Enogen's alpha amylase is inactive while the kernel remains intact, but when the kernel is ground, the enzyme is released out of the kernel to break down the starch on its own. With the use of Enogen grain as feedstock, the need to add commercial alpha amylase in liquid form is practically eliminated during the process.

Enogen grain also hastens the fermentation process as it reduces or eliminates the need to adjust pH with chemicals. Thus, more ethanol can be produced from the same amount of corn. Process performance is also improved by reducing the cost of heating up and cooling down the mixture and thus, reducing energy and water use. A 100-million gallon plant that feeds Enogen corn could save 450,000 gallons of water, 1.3 million KWh of electricity and 244 billion BTUs of natural gas, while also reducing carbon dioxide emissions by 106 million pounds, according to Syngenta.

A number of bioethanol producers in Iowa have started using the Enogen corn on a commercial basis as previous trials produced encouraging results. They now partner with Syngenta to sign up farmers to grow Enogen under specific production and stewardship requirements. In exchange, farmers are guaranteed a 40-cent per bushel premium.