Global transcription machinery engineering (gTME) was employed to engineer xylose metabolism. Mutation of the transcription factor gene Sptl5 was introduced by error-prone PCR, followed by screening on media using xylose as the sole carbon source. One recombinant strain growing well on such media was chosen for further research. This strain showed modest growth rates in the media containing 50 ...

This study investigated the conversion of Lemna minor biomass to bioethanol. The biomass was pre-treated by steam explosion (SE, 210°C, 10 min) and then subjected to simultaneous saccharification and fermentation (SSF) using Cellic® CTec 2 (20 U or 0.87 FPU g(-1) substrate) cellulase plus β-glucosidase (2 U g(-1) substrate) and a yeast inoculum of 10% (v/v or 8.0×10(7) cells mL(-1)). At a subst...

Saccharomyces cerevisiae Y5 (CGMCC no. 2660) and Issatchenkia orientalis Y4 (CGMCC no. 2159) were combined individually with Pichia stipitis CBS6054 to establish the cocultures of Y5 + CBS6054 and Y4 + CBS6054. The coculture Y5 + CBS6054 effectively metabolized furfural and HMF and converted xylose and glucose mixture to ethanol with ethanol concentration of 16.6 g/L and ethanol yield of 0.46 g...

A comparative study of extruded and ground maize meals as raw materials for the production of regular (12°P) and high gravity (20°P) worts was devised. Extruded water solubility index (WSI) was higher (9.8 percentage units) and crude fat was lower (2.64 percentage units) compared to ground maize. Free-amino nitrogen compounds (FAN), pH, and glucose were evaluated in regular and high gravity wor...

Because of the high energy consumption for fermentor cooling, the isolation of thermo-tolerant Acetobacter strains for vinegar production has a high priority. The aims of this study were the isolation and identification of a high ethanol-thermo-tolerant Acetobacter spp. from grapes as well as the optimization of conditions for increasing the acetic acid production. The grape e...

Because of the high energy consumption for fermentor cooling, the isolation of thermo-tolerant Acetobacter strains for vinegar production has a high priority. The aims of this study were the isolation and identification of a high ethanol-thermo-tolerant Acetobacter spp. from grapes as well as the optimization of conditions for increasing the acetic acid production. The grape e...

Dilute acid pretreatment is an established method for hydrolyzing the methylglucuronoxylans of hemicellulose to release fermentable xylose. In addition to xylose, this process releases the aldouronate methylglucuronoxylose, which cannot be metabolized by current ethanologenic biocatalysts. Enterobacter asburiae JDR-1, isolated from colonized wood, was found to efficiently ferment both methylglu...

*Correspondence: J. Y. Zhu, Forest Products Laboratory, 1 Gifford Pinchot Dr., Madison, WI, USA e-mail: [email protected] Poplar NE222 (Populus deltoides Bartr. ex Marsh×P. nigra L.) wood chips were pretreated in a 390 L pilot-scale rotating wood-pulping digester using a dilute sulfite solution of approximately pH 1.8 at 160°C for 40 min for bioconversion to ethanol and lignosulfonate (LS). An est...

Ethanol production in a simultaneous saccharification and fermentation (SSF) process using waste textiles as feedstock was studied. The dissolution pretreatment of waste textiles in ortho-phosphoric acid resulted in at least 2 fold improvement in enzymatic hydrolysis rate and reducing sugar yield. The reducing sugars obtained from dyed or discolored waste textiles by cellulase hydrolysis demons...

poly-β-hydroxybutyrate (phb), produced by several species of bacteria, has attracted great attention as a biodegradable and biocompatible compound with almost similar properties of polypropylene. unfortunately, its use is currently limited due to high production costs. one of the most common methods for overcoming this constraint is the use of inexpensive substrates, like methanol. another stra...