The fermentability of a corn cob, acid-hydrolysed hemicellulose by Pichia stipitis was considerably improved by pre-treatment with Ca(OH)2. The total sugars utilized and ethanol yield for the untreated hydrolysate were 18% and 0.21 g/g, respectively, compared with 82% and 0.32 g/g respectively for the treated material. Adaptation of the yeast to the hydrolysate resulted in a significantly highe...

BACKGROUND As the most abundant renewable resources, lignocellulosic materials are ideal candidates as alternative feedstock for bioethanol production. Cassava residues (CR) are byproducts of the cassava starch industry which can be mixed with lignocellulosic materials for ethanol production. The presence of lignin in lignocellulosic substrates can inhibit saccharification by reducing the cellu...

In this study bio-hydrogen and bioethanol were produced from dry biomass of water hyacinth by microbial fermentation under influence of zinc oxide nanoparticles. For fermentative bio-hydrogen production biomass was first pretreated and then saccharified into fermentable sugars by enzymes. Sugars of enzymatic hydrolysis were xylose and glucose with concentration of 9.0% and 8.0% respectively. Fo...

Clostridium ljungdahlii is a strictly anaerobic acetogene known for its ability to ferment a wide variety of substrates to ethanol and acetate. This bacterium presents a complex anaerobic metabolism including the acetogenic and solventogenic phases. In this study, the effect of various carbon sources on triggering the metabolic shift toward solventogenesis was considered. The bacterium was grow...

Thermoanaerobacterium saccharolyticum has been engineered to produce ethanol at ∼90% theoretical yield and titer of 70 g/L. Its ethanol-producing ability has drawn attention to its metabolic pathways, which could potentially be transferred to other organisms of interest. Here we report that the iron-containing AdhA is important for ethanol production in the high-ethanol strain of T. saccharolyt...

BACKGROUND Conventional corn dry-grind ethanol production process requires exogenous alpha and glucoamylases enzymes to breakdown starch into glucose, which is fermented to ethanol by yeast. This study evaluates the potential use of new genetically engineered corn and yeast, which can eliminate or minimize the use of these external enzymes, improve the economics and process efficiencies, and si...

Perennial biomass from grasslands managed for conservation of soil and biodiversity can be harvested for bioenergy. Until now, the quantity and quality of harvestable biomass from conservation grasslands in Minnesota, USA, was not known, and the factors that affect bioenergy potential from these systems have not been identified. We measured biomass yield, theoretical ethanol conversion efficien...

Based on elementary mode analysis, an Escherichia coli strain was designed for efficient conversion of glycerol to ethanol. By using nine gene knockout mutations, the functional space of the central metabolism of E. coli was reduced from over 15,000 possible pathways to a total of 28 glycerol-utilizing pathways that support cell function. Among these pathways are eight aerobic and eight anaerob...

BACKGROUND Integration of second-generation (2G) bioethanol production with existing first-generation (1G) production may facilitate commercial production of ethanol from cellulosic material. Since 2G hydrolysates have a low sugar concentration and 1G streams often have to be diluted prior to fermentation, mixing of streams is beneficial. Improved ethanol concentrations in the 2G production pro...

The application of high-potential thermotolerant yeasts is a key factor for successful ethanol production at high temperatures. Two hundred and thirty-four yeast isolates from Greater Mekong Subregion (GMS) countries, i.e., Thailand, The Lao People's Democratic Republic (Lao PDR) and Vietnam were obtained. Five thermotolerant yeasts, designated Saccharomyces cerevisiae KKU-VN8, KKU-VN20, and KK...