FERMENTATION MEDIA AND METHODS FOR THE CONVERSION OF GLYCEROL TO ETHANOL

摘要

The present invention provides methods of converting a carbon source into ethanol efficiently and at reduced costs compared to prior art processes. In one embodiment, the method comprises culturing an ethanologenic microorganism that produces an extracellular enzyme such as a protease capable of hydro lyzing unhydrolyzed nitrogen sources in a suitable culture medium wherein the culture medium comprises a mixture of a carbon source such as glycerol, sugars and complex carbohydrates and an unhydrolyzed nitrogen source such as soybean meal, soybean flour, cottonseed flour or other nitrogen-rich materials as nutrients, wherein the microorganism converts the carbon source into ethanol. In one embodiment, the method comprises converting a carbon source into ethanol wherein the method does not require the addition of enzymes to the cell culture or cell culture medium produced outside the cell culture system such as the addition of semi-purified or purified enzyme preparations.