Fabrication and Nanomechanical Characterization of Thermoplastic Biocomposites Based on Chemically Treated Lignocellulosic Biomass for Surface Engineering Applications

Diverse applications of polymeric materials have prompted development of eco-friendly, efficient, and economical materials. These characteristics can be obtained by incorporating appropriate fillers in the polymeric matrix. The objective of this work is to investigate impact of aqueous glycerol (Gly) treated rice husk (RH) on surface mechanical...

Engineering Saccharomyces cerevisiae for Succinic Acid Production From Glycerol and Carbon Dioxide

Previously, our lab replaced the endogenous FAD-dependent pathway for glycerol catabolism in S. cerevisiae by the synthetic NAD-dependent dihydroxyacetone (DHA) pathway. The respective modifications allow the full exploitation of glycerol’s higher reducing power (compared to sugars) for the production of the platform chemical succinic acid ...

Carbon dioxide fixation by Calvin-Cycle enzymes improves ethanol yield in yeast

Background Redox-cofactor balancing constrains product yields in anaerobic fermentation processes. This challenge is exemplified by the formation of glycerol as major by-product in yeast-based bioethanol production, which is a direct consequence of the need to reoxidize excess NADH and causes a loss of conversion efficiency. Enabling the use of...

Pt/Al2O3 Catalyzed 1,3-Propanediol Formation from Glycerol using Tungsten Additives

Screening of four commercial catalysts (Pt/Al2O3, Pt/SiO2, Pd/Al2O3, and Pd/SiO2) and four acidic additives (hydrochloric, tungstic, phosphotungstic, and silicotungstic acids) shows that the combination of a platinum hydrogenation catalyst with tungsten containing acidic additives yields 1,3-propanediol from aqueous glycerol. The performance of...

Numerical study on dispersion of dilute glycerol-water mixtures in channel flow

In this work we developed a numerical model for channel flow on a pore or micro scale. A straight channel was simulated with a flow regime of Re=0.03 and Re=0.3 (comparable to typical fluid flow in petroleum reservoirs) to visualize the characteristics of flow and dispersion up to the Fickian limit. The objective of this study was to quantify...

Microbial community engineering for biopolymer production from glycerol

In this work, the potential of using microbial community engineering for production of polyhydroxyalkanoates (PHA) from glycerol was explored. Crude glycerol is a by-product of the biofuel (biodiesel and bioethanol) industry and potentially a good substrate for bioplastic production. A PHA-producing microbial community was enriched based on...

Diversity of microbial communities in open mixed culture fermentations: Impact of the pH and carbon source

Anaerobic fermentation by an open mixed culture was investigated at different pH values (4–8.5) and with three substrates (glucose, glycerol and xylose). The populations established in each condition were assessed by denaturing gradient gel electrophoresis analysis of the 16S ribosomal RNA gene fragments. The fermentation pattern and the...

Directing product formation by mixed culture fermentation

Our society is dealing with the shortage of fossil fuels and chemical feedstocks and, on the other hand, with the increase of wastes generated by municipalities, agriculture and industries. Biobased industry, the conversion of renewable resources or wastes to chemicals and fuels, by microbial fermentations or enzymes has been receiving...

Application and assessment of experimental methods to study the cytosolic primary metabolism of yeast

Although a large part of the metabolism of the yeast Saccharomyces cerevisiae, has been clarified, there are a number of issues that still limit the predictive power of metabolic models for this organism. The dissertation aims to improve the collection of data for metabolic models through application and assessment of different experimental...