Biochemical and Biomolecular Engineering Commons^™

Co-Substrate Fermentation Of Jerusalem Artichoke Tubers And Crude Glycerol To Butanol With Integrated Product Recovery, Tahereh Sarchami

Electronic Thesis and Dissertation Repository

Butanol has long been considered a potential advanced liquid biofuel, in addition to its current application as an industrial solvent. It can be produced biologically; however, the conventional ABE fermentation suffers from many limitations, including low butanol titer, high cost of traditional raw materials, end-product inhibition and high butanol recovery costs. Possible solutions are the use of renewable low-cost feedstocks, genetic manipulations of Clostridia spp. to improve the strains’ butanol titer and tolerance, advanced fermentation techniques, and in-situ product recovery technologies.

In order to overcome some of these limitations, the overall goal of this thesis was to develop a process …

Fabrication And Cross-Linking Of L-Aspartic Acid Functionalized Poly(Ester Amide)-Based Tissue Engineering Scaffolds, Shuyu Liu

Electronic Thesis and Dissertation Repository

Scaffold fabrication is essential in tissue engineering. Amino acid based poly(ester amide)s (PEAs) have been investigated as scaffold materials due to their non-toxic degradation byproducts, and easily tunable mechanical and biological properties. However, L-aspartic acid functionalized PEAs showed poor morphological stability when immersed in buffer. This work focuses on the further functionalization of L-aspartic acid based PEAs, scaffold fabrication and cross-linking of the scaffold to improve morphological stability. Photo-cross-linkable and thermally cross-linkable PEAs were synthesized successfully and characterized. Two scaffold fabrication methods were applied: 1) electrospinning was applied to photo-cross-linkable PEAs, followed by UV treatment to cross-link electrospun scaffolds; 2) …

Abe Fermentation From Low Cost Substrates, Kai Gao

Electronic Thesis and Dissertation Repository

The high cost of substrate and product inhibition in the fermentation broth remains two major problems associated with bio-butanol production. This thesis aims to solve these problems by examining abundant lignocellulosic biomass as potential feedstocks and exploring novel substrates such as carbohydrates derived from microalgae for ABE fermentation. The commonly observed toxic effect after pretreatment of lignocelluslosic biomass was removed by resin adsorption, where the resin could also serve as an in-situ butanol recvoery devices.

Corn cobs (an agricultural waste), switchgrass (an energy crop) and phragmites (an invasive plant in North America) were investigated as substrates for ABE fermentation by …

Biohydrogen And Biomethane Production From Lignocellulosic Biomass, Chinaza Okeoghene Akobi

Electronic Thesis and Dissertation Repository

The main purpose of this study was to investigate the impact of furfural on mixed cultures during fermentative hydrogen production from lignocellulosic biomass. Small batch studies using synthetic lignocellulosic hydrolysate grown on mesophilic mixed cultures, revealed a threshold furfural concentration of greater than 1 g/L with enhancement to the yields (from the control) observed at 0.5 g/L furfural (at initial substrate-to–biomass (S°/X°) ratios of 0.5 and 1 gCOD/gVSS) and at both 0.5 g/L and 1 g/L furfural (at S°/X° of 2 and 4 gCOD/gVSS). This study was scaled-up from 200 mL to 11 L working volume batches, using half the …

Ginseng Polysaccharides Nanoparticles - Synthesis, Characterization, And Biological Activity, Kazi Farida Akhter

Electronic Thesis and Dissertation Repository

North American (NA) ginseng is a widely used medicinal plant. Polysaccharides (PS), the major medicinal fractions derived from NA ginseng root, have been shown several biological activities including anti-carcinogenic, anti-aging, immunostimulatory and antioxidant activity. This work focused on nanoprocessing of ginseng PS for enhancing their immunostimulation. Herein, we have developed a novel microfluidic approach to synthesize ginseng PS nanoparticles (NPs) from NA ginseng root. The microfluidics was found to provide unimodal PS spheres down to 20 nm with very narrow particle size distributions. In addition, the immunostimulating effect was investigated on Murine macrophage cell lines, with the results revealing an …

Direct Conversion Of Wet Microalgae And Oleaginous Yeast To Biodiesel Using Ionic Liquids, Valerie Orr

Electronic Thesis and Dissertation Repository

This thesis examined the development of an oleaginous yeast or microalgae based biorefinery process. First, improvements were made to the Nile Red assay, a high-throughput method for monitoring lipid accumulation in oleaginous organisms resulting in a significantly more reproducible and accurate assay. This assay was then used to optimize lipid production during heterotrophic cultivation of microalgae on glucose using response surface methodology resulting in microalgae with high lipid content (37.6% wt.). In order to improve the renewability of heterotrophic lipid production, both oleaginous yeast and microalgae were cultivated using pyrolytic sugars, produced via fast pyrolysis of pinewood waste. The effects …

Hydrothermal Liquefaction Of High-Water Content Biomass And Waste Materials For The Production Of Biogas And Bio-Crude Oil, Laleh Nazari

Electronic Thesis and Dissertation Repository

Growing interest in renewable energies due to shrinking reserves of fossil fuels and climate change concerns have led to extensive research towards gaseous and liquid fuels production from renewable energy resources such as biomass and wastes. Energy generation from municipal and industrial wastes such as wastewater sludge is also environmental friendly way to deal with large volume of waste disposal with the additional advantage of eliminating part of the indirect greenhouse gas emissions from energy crops-derived biofuels.

In this thesis, a novel process for co-production of biogas and bio-crude oil from high-water-content wastewater sludge through hydrothermal liquefaction (HTL) treatments is …

Studies On Nanocomposite Coating Produced By Laser-Assisted Process To Prevent Silicone Hydrogels From Bio-Fouling, Vishnuvardhana Wuppaladhodi

Electronic Thesis and Dissertation Repository

In this thesis, silver nanoparticles incorporated into polyvinylpyrrolidone (PVP) were deposited on silicone hydrogel to improve the hydrophilicity of the silicone hydrogel and prevent the growth of bacteria. Two different processes were employed to produce Ag nanoparticles: (1) Process-A is a photochemical reduction; (2) Process-B is laser ablation in liquid. Following that, MAPLE process was employed to deposit the Ag-PVP nanocomposites on the surface of silicone hydrogel. A solid-state pulsed laser (Nd:YAG) with a wavelength of 532 nm at a fluence of 50.4 mJ/cm² was used in the MAPLE system to deposit Ag-PVP nanocomposite coating. Our results indicate that …

Fermentative Processes Requiring Low Solubility Feed Gases: An Investigation Into Gas-Dependent Microorganisms, Eric W. Doerr

Electronic Thesis and Dissertation Repository

Two bioprocesses were separately investigated based on their common interest of using gaseous substrates that have low solubility. The first process involved the development of a mixed culture using two organisms capable of utilizing glycerol and carbon monoxide separately to increase biobutanol production, while the second process involved an investigation of different production media used in aerobic xanthan production of Xanthomonas campestris with pressurization effects. It was determined that Clostridium pasteurianum should be used with an organism like Clostridium carboxidivorans or Eubacterium limosum in order for butyrate uptake at 3 g/L to occur with a minimum 0.1 g/L butyrate production. …

Minor Whey Protein Purification Using Ion-Exchange Column Chromatography, Naeimeh Faraji Dizaji

Electronic Thesis and Dissertation Repository

This thesis is concerned with application of mechanistic models for recovery and purification of two minor milk proteins to develop an efficient and robust process. A fundamental and quantitative understanding of the underlying mechanisms assists to evaluate chances and challenges in non-linear chromatography.

The first chapter considers adsorption isotherm data of two minor whey proteins on cation exchanger under various conditions and used as the basis to develop a predictive approach for correlating adsorption behavior using a mechanistic isotherm model. The SMA isotherm model explicitly considers the contributions of protein-adsorbent and protein-protein interactions in the simulation of salt gradients in …

Recovery Of Valuable Chemicals From Agricultural Waste Through Pyrolysis, Mohammad M. Hossain

Electronic Thesis and Dissertation Repository

Agricultural crop residues are a source of inexpensive biomass to convert into bioproducts. The recovery of valuable chemicals from plant waste would partly solve the disposal issue and offer a more environmentally friendly alternative to synthetic chemical production. One approach to separate and concentrate valuable chemicals from biomass is pyrolysis using a batch reactor process. A mechanically fluidized reactor (MFR) was developed to pyrolyze biomass from ambient to temperatures near 600 °C, forming gases that are then condensed in an ice-chilled condenser to form a bio-oil. The bio-oil produced by the MFR can be separated within temperature ranges, termed one-dimensional …

Polymeric Superparamagnetic Nanoparticles For Drug Delivery Applications, Leena Mohammed

Electronic Thesis and Dissertation Repository

Drug delivery systems based on magnetic nanoparticles present a promising avenue for controlled targeted therapeutics, especially in cancer therapy. Conventional systematic therapeutics encompasses numerous side effects due to its limited selectivity between healthy and cancerous cells. In this thesis, novel polymeric-metallic hybrid nanoaggregates were developed to address this challenge. Magnetite nanoparticles were synthesized via precipitation of iron oxide and was surface modified using a unique chitosan derivative, glycol chitosan (GC), loaded with progesterone for potential hormonal therapy application for breast cancer. Surface characterizations techniques, in vitro drug release kinetics, investigation of progesterone release mechanism by mathematical modeling, and cell cytotoxicity …

A Study Of Low C/N Ratio Waste Water Treatment Using Fluidized Bed Bioreactor, Kai Li

Electronic Thesis and Dissertation Repository

In wastewater treatment field, one of the severe challenges is the handling of ammonia-rich wastewater with a low C/N ratio. The failure of nitrogen treatment can lead to adverse ecological and biological effects including depletion of dissolved oxygen, eutrophication, toxicity to aquatic life, and reduction in the suitability of water for reuse. Conventionally, extra organic carbon dosing is required in treating low C/N wastewater. Alternately, partial nitrification is of interest as an emerging technology for its’ lesser need of organic carbon addition and cost savings in aeration. In this study, a lab-scale partial nitrification fluidized bed bioreactor (PNFBR) and a …