ABSTRACT
Ethanol (chemical formula C2H5OH) can be produced from biomass from its sugar, starch, and cellulosic components. The most common bioconversion process is through the action of certain specic yeasts or enzymes produced by microbes that act on the sugar, starch, or cellulosic components that convert these into ethanol. Ethanol production from sugars is the most common process and makes use of yeast for conversion into ethanol, a one-step fermentation process. The most popular yeast is Saccharomyces cerevisiae, which has now been genetically modied to improve its ability to produce high percentages of ethanol while able to withstand the high sugar concentration of some biomass. Ethanol from sugar or starchy crops is termed the “rstgeneration” ethanol as opposed to “second-generation” ethanol that comes from lignocellulosic biomass. Plant cellulose is considered the most abundant renewable resource in the world.
