Carbohydrate is a crucial resource and energy substance. About 200 billion tons of carbon are fixed by green plants every year. The energy is up to 3×1021 J, which corresponds to 10 times the amount of energy consumed annually worldwide. Using biotechnology, we can convert the most renewable biomass resources on earth into simple carbohydrates and further into energy sources (e.g., fuel ethanol, biodiesel, hydrogen) and chemical platform compounds (e.g., organic acids, organic alcohols, esters).
