Inexpensive, sustainable production of bioethanol
Biofuels may not be the panacea once thought, but if sustainable production methods can be achieved then petrol's days could be numbered. For instance, ethanol, a popular fuel traditionally produced from sugar cane and other food-related crops, can also be produced by fermenting lignocellulosic biomass sourced from wood residue and other waste products. Unfortunately, until now, ethanol production from lignocellulosic biomass has not been competitive in terms of costs. The CO-PRODUCTION BIOFUELS consortium aimed to overcome this obstacle by optimising fermentation technology. TMO sought to maximise rates of ethanol production and focussed on the potential of high-temperature ethanologenic microorganisms. They discovered that lactate dehydrogenase deficient (LDH-) strains, which are unable to generate lactate, performed best. Surprisingly, TMO found that the microorganisms could be cultured for extended periods (up to six months) without requiring antibiotic intervention. The LDH- microorganism was put to the test during CO-PRODUCTION BIOFUELS using wheat straw hydrolysate as a feedstock. The trial was successful for both batch and continuous modes of fermentation. The full results of the EESD-sponsored research are available from TMO. Future work will focus on ethanologenesis from simple sugars, such as glucose and xylose. Thanks to TMO and its partners, the outlook for bioethanol looks brighter than ever.
