Bradley A. Saville

• University of Toronto

International Civil Aviation Organization member states need to develop national strategies for sustainable aviation fuel (SAF) production to reduce greenhouse gas emissions from aviation. In this work, we developed a framework to estimate the national SAF potential and applied it to a case study for canola SAF in Canada. Specifically, we answered...

The synthesis of sugar fatty acid esters (SFAEs) from lignocellulosic biomass and oleic acid (C18:1) was catalyzed by immobilized‐stabilized derivatives of Candida antarctica lipase B in a methyl ethyl ketone medium. After steam‐explosion pretreatment of mixed hardwoods and enzymatic hydrolysis at 15%wt solids, xylose and glucose were purified/conc...

In this study, concepts of systematic mapping (SM) were used to conduct a literature review covering the research on the production and recovery of sugars from lignocellulosics to synthesize bioproducts, mostly xylose-derived products. The SM approach constitutes a rigorous evidence review methodology used to catalog evidence, identifying knowledge...

Objectives Pathogenic bacterial infections in the gastrointestinal tract compromise the health and function of the gut microbiome, and the rising incidence of antibiotic-resistant bacterial strains has resulted in initiatives seeking alternative treatments. Some prebiotic fibers, such as mannan-oligosaccharides (MOS), may be a promising alternative...

Cold weather operability is sometimes a limiting factor in the use of biodiesel blends for transportation. Regional temperature variability can therefore influence biodiesel adoption, with potential economic and environmental implications. This study assesses present and future biodiesel cold weather operability limits in North America according to...

Indonesia and Malaysia are net importers of animal feed products to meet the demand of their domestic livestock industries. These countries are also the largest producers and exporters of palm kernel cake (PKC), an animal feed waste by‐product from the palm industry that is used primarily as a ruminant feed. Prior work demonstrated that the bioetha...

This study presents a novel computational fluid dynamics (CFD) model to investigate important aspects of the complex high-solids enzymatic hydrolysis (HSEH) process. The uniqueness of this CFD model lies in integrating the biochemical reaction taking place in the secondary phase and the corresponding mass transfer of the products from the secondary...

Replacing conventional gasoline with mid-level ethanol blends (15–30% ethanol by volume) can reduce fossil fuel use and greenhouse gas (GHG) emissions but require vehicle compatibility. This study quantifies the changes in fuel volumes and well-to-wheel (WTW) GHG emissions associated with potential mid-level ethanol blend deployment in Canada's lig...

This study investigates life cycle GHG emissions of jet fuel produced via the hydroprocessed esters and fatty acids (HEFA) pathway from canola grown in western Canada, with a focus on characterizing regional influences on emissions. We examine effects of geographical variations in soil type, agricultural inputs, farming practises, and direct land u...

A computational fluid dynamics model was developed to represent high‐solids enzymatic hydrolysis. This model accounted for the transient and multiphase (solids‐slurry) nature of the high‐solids enzymatic hydrolysis process. The model investigated the effect of slurry viscosity, rotational speed, and two impeller configurations on the distribution o...

A key motivation behind the development and adoption of industrial biotechnology is the reduction of negative environmental impacts. However, accurately assessing these impacts remains a formidable task. Environmental impacts of industrial biotechnology may be significant across a number of categories that include, but may not be limited to, nonren...

This paper evaluates differences in life cycle greenhouse gas emissions of corn stover ethanol produced in the U.S. Midwest, as estimated by the life cycle-based software GHGenius 4.03a, GREET 2013, and GREET 2015. Life cycle assessments are not typically conducted using more than one software package, but comparisons such as the analysis in this p...

Kt/V is a nondimensional number and a scaling parameter that has, with arbitrary definitions, been recast as a measure of dialysis by Gotch and Lysaght. This editorial discusses the concept of nondimensional numbers within the context of dialysis measurement, modeling, and medical evidence. It concludes that Gotch’s Kt/V, Lysaght’s Kt/V, and standa...

The paper presents techno-economic analyses and life cycle assessments (LCA) of the two major gasification processes for producing hydrogen from biomass: fluidized bed (FB) gasification, and entrained flow (EF) gasification. Results indicate that the thermal efficiency of the EF-based option (56%, LHV) is 11% higher than that of the FB-based option...

This study presents techno-economic analyses and life cycle assessments of four hydrogen production technologies using natural gas as a feedstock. Steam methane reforming, auto-thermal reforming and two innovative technologies: syngas chemical looping (SCL) and chemical looping reforming (CLR) are evaluated and compared. Thermodynamic analysis indi...

The focus of this work is to model the hydrodeoxygenation process to produce renewable jet fuel and co-products from low-input oilseeds, specifically camelina, carinata (non-edible oil) and used cooking oil (UCO), taking into account the fatty acid compositions by incorporating the stoichiometric hydrodeoxygenation reactions. This methodology provi...

The literature analyzes changes in vehicle attributes that can improve fuel economy to meet Corporate Average Fuel Economy (CAFE) standards. However, these analyses exclude either vehicle price, size, acceleration or technology advancement. A more comprehensive examination of the trade-offs among these attributes is needed, this case study focuses...

This paper evaluates the financial viability of renewable jet fuel production, from two oilseed crops Camelina sativa (camelina) and Brassica carinata (carinata) and used cooking oil (UCO), by the hydrodeoxygenation pathway. A Monte Carlo analysis is performed to examine the robustness of the financial performance by taking into consideration key u...

Lignocellulosic ethanol has potential for lower life cycle greenhouse gas emissions compared to gasoline and conventional grain-based ethanol. Ethanol production ‘pathways’ need to meet economic and environmental goals. Numerous life cycle assessments of lignocellulosic ethanol have been published over the last 15 years, but gaps remain in understa...

The fuel economy of gasoline vehicles will increase to meet 2025 corporate average fuel economy standards (CAFE). However, dedicated compressed natural gas (CNG) and battery electric vehicles (BEV) already exceed future CAFE fuel economy targets because only 15% of non-petroleum energy use is accounted for when determining compliance. This study ai...

Bulk chemicals production from biomass may compete with biofuels for low-cost and sustainable biomass sources. Understanding how alternative uses of biomass compare in terms of financial and environmental parameters is therefore necessary to help ensure that efficient uses of resources are encouraged by policy and undertaken by industry. In this pa...

Enzymatic hydrolysis of hardwood substrates yields soluble sugars, which are a carbon source for producing ethanol and butanol. However, as the substrate and water are mixed, a viscous, heterogeneous slurry forms. The result is reduced mixing performance, mass transfer, and enzyme-substrate contact, all of which negatively affect sugar titers. In t...

This paper examines impacts of regional factors affecting biomass and process input supply chains and ongoing technology development on the life cycle greenhouse gas (GHG) emissions of ethanol production from corn stover in the U.S. Corn stover supply results in GHG emissions from −6 gCO2eq./MJ ethanol (Macon County, Missouri) to 13 gCO2eq./MJ etha...

This paper aims to comprehensively distinguish among the merits of different vehicles using a common primary energy source. In this study, we consider compressed natural gas (CNG) use directly in conventional vehicles (CV) and hybrid electric vehicles (HEV), and natural gas-derived electricity (NG-e) use in plug-in battery electric vehicles (BEV)....

Our study evaluates life cycle energy use and GHG emissions of lignocellulosic ethanol and bioelectricity use in U.S. light-duty vehicles. The well-to-pump, pump-to-wheel, and vehicle cycle stages are modeled. All ethanol (E85) and bioelectricity pathways have similar life cycle fossil energy use (∼ 100 MJ/100 vehicle kilometers traveled (VKT)) and...

The cost of cellulases remains a key issue in the production of cellulosic ethanol, and the impact of enzymes on greenhouse gas (GHG) emissions of cellulosic ethanol has received little attention. This study evaluates life cycle emissions and cellulase production costs for bioethanol production, considering on-site and off-site production options....

The production of biofuel from cellulosic residues can have both environmental and financial benefits. A particular benefit is that it can alleviate competition for land conventionally used for food and feed production. In this research, we investigate greenhouse gas (GHG) emissions associated with the production of ethanol, biomethane, limonene an...

The first Feed-in-Tariff (FiT) program in North America was recently implemented in Ontario, Canada to stimulate the generation of electricity from renewable sources. The life cycle greenhouse gas (GHG) emissions and economics of electricity generation through anaerobic digestion (AD) of household source-separated organic waste (HSSOW) are investig...

Enzymatic hydrolysis at high solids loadings is key to scale-up of lignocellulosic biochemical conversion processes, because of potentially higher sugar and ethanol titers and lower hydraulic loads. However, high solids loadings can pose rheological challenges, reduce mass and heat transfer efficiency, and increase the concentration of enzyme inhib...

Overview of Pretreatment TechnologiesPretreatment ClassificationLaboratory vs. Commercial Scale Pretreatment—What Do We Really Know?Process Issues and Trade-OffsEconomicsConclusions

Supplementary material is available on the publisher's Web site along with the published article. Calculations_24.xls -contains some additional figures. Loss_of_RFF_calc6.xls - contains loss of RRF calculation.

Non-dimensional analysis is a powerful approach that can be applied to multivariate problems to better understand their behaviour and interpret complex interactions of variables. It is has not been rigorously applied to the parameters that define renal dialysis treatments and may provide insight into the planning of hemodialysis treatments. Bucking...

In this article, the mechanisms of thermoinactivation of glucose isomerase (GI) from Streptomyces rubiginosus (in soluble and immobilized forms) were investigated, particularly the contributions of thiol oxidation of the enzyme's cysteine residue and a "Maillard-like" reaction between the enzyme and sugars in high fructose corn syrup (HFCS). Solubl...

Studies were conducted on maltodextrin saccharification and on simultaneous saccharification and fermentation (SSF) with various commercial glucoamylases. In kinetics studies, none of the glucoamylases were able to completely convert maltodextrin into glucose. Typically, about 85% conversion was obtained, and glucose yields were about 75%. Typicall...

These studies were designed to explore the feasibility of using immobilized enzymes for the deinking of laser-printed and photocopied wastes. Comparative experiments with soluble and immobilized cellulase showed that immobilized cellulase can produce superior deinking results, despite the fact that immobilized cellulase has less than 10% of the act...

The performance of cellulase and amylase immobilized on siliceous supports was investigated. Enzyme uptake onto the support depended on the enzyme source and immobilization conditions. For amylase, the uptake ranged between 20 and 60%, and for cellulase, 7-10%. Immobilized amylase performance was assessed by batch kinetics in 100-300 g/L of corn fl...

The degradation of phenol by tyrosinase immobilized on chemically modified sodium aluminosilicate (NaA), calcium aluminosilicate (CaA), and silica gel was studied. Phenol conversion by immobilized tyrosinase ranged between approximately 15% and 60%, depending upon the initial phenol concentration, pH, and enzyme loading. Tyrosinase immobilized on C...

The vitreous humor is a viscous fluid occupying the space between the lens and retina of the eye. A number of diseases that can affect the vitreous or the surrounding retina can be treated by administration of various therapeutic drugs. Due to physiological barriers within the eye that prevent drug in the systemic circulation from entering the vitr...

The production of l-3,4-dihydroxyphenylalanine from mushroom tyrosinase immobilized on chemically modified supports, sodium aluminosilicate (NaA) and calcium aluminosilicate (CaA) (two separate forms of zeolite) was studied. Tyrosinase was immobilized on the supports using glutaraldehyde (1%, w/v) as a cross-linking agent. The uptake of tyrosinase...

The inactivation of the catecholase activity of mushroom tyrosinase was investigated under nonaqueous conditions. The enzyme was immobilized on glass beads, and assays were conducted in chloroform, toluene, amyl acetate, isopropyl ether, and butanol. The reaction components were pre-equilibrated for 2 weeks with a saturated salt solution at a water...

The production of l-3,4 dihydroxyphenylalanine (l-DOPA) from mushroom tyrosinase immobilized on chemically modified nylon 6,6 membranes was investigated in a batch reactor.The effects of product inhibition, oxygen partial pressure, and scaleup upon l-DOPA production rates and tyrosinase activity were studied. l-DOPA production rates were strongly i...

The majority of eyes that receive drug therapy exhibit some form of pathophysiological degradation. Two common pathophysiological states are retinal inflammation, which results in breakdown of the blood-retinal barrier, and aphakia. The purpose of this study was to examine the effects of aphakia and changes in retinal permeability and vitreous diff...

The purpose of this study was to determine how the position and volume of an intravitreal injection affect the distribution and elimination of drug from the vitreous humor. A mathematical model that had been developed and used previously to study drug distribution in the vitreous humor of the rabbit eye was modified to match the physiology of the h...

Direct intravitreal injection of drug is a common method for treating diseases of the retina or vitreous. The stagnant nature of the vitreous humor and surrounding tissue barriers creates concentration gradients within the vitreous that must be accounted for when developing drug therapy. The objective of this research was to study drug distribution...

The production of L-DOPA immobilized on chemically modified nylon 6,6 membranes was studied in a batch reactor. Tyrosinase was immobilized on nylon using glutaraldehyde as a crosslinking agent. The effects of membrane pore size and glutaraldehyde concentration upon enzyme uptake and L-DOPA production were investigated. Enzyme uptake was unaffected...

Mushroom tyrosinase was immobilized on Nylon-66 through covalent crosslinking. Its catecholase activity was studied in order to assess the efficiency of the method. Fifty per cent of the catecholase activity in the medium was immobilized onto the support. Since the catecholase activity is known to be subject to rapid inactivation, studies were cond...

Controlled release ocular inserts have been found to increase the amount of drug which is absorbed into the aqueous humour when compared to eyedrops. Systemic absorption following delivery using a controlled release insert has been found to be dependent on the release rate of the insert. The objective of this study was to determine if ocular insert...

The effect of local cyclosporine therapy upon corneal transplant survival was investigated. A high risk rabbit model with vascularized corneas was used to assess the efficacy of subconjunctivally implanted degradable devices for cyclosporine therapy. Animals were divided into four groups, receiving either no therapy, a placebo PLGA device, or drug...

Studies were conducted in rabbits to determine the ocular distribution and elimination of cyclosporine, with the objective of developing a comprehensive pharmacokinetic model. Following a bolus dose into the anterior chamber, drug levels were measured in the aqueous humor, cornea, iris/ciliary body, lens, sclera, and conjunctiva. Cyclosporine was r...

Studies were conducted to evaluate the efficacy of direct injections of cyclosporine (CsA) into the anterior chamber for the prevention of corneal allograft rejection in Dutch Belted rabbits. The mean survival time (MST) of grafts progressively increased from 50 to 89 days as the CsA concentration in the dose was increased from 1 to 10 mg/mL. Injec...

The primary route into the eye for many drugs is transcorneal permeation. A better understanding of the mechanisms involved in transcorneal permeation could lead to improvements in drug dosage forms or the development of drug delivery devices which enhance the ocular bioavailability of drugs. A corneal permeation model has been developed which can...

The relationship between enzyme inactivation and the concentration of oxygen in the reaction environment was studied using glutamine synthetase. Batch incubations of the enzyme were conducted under different oxygen partial pressures in a mixed-function oxidase model system. Enzyme activity was monitored using a transferase reaction assay. Studies s...

The uptake and metabolism of lipophilic compounds by the liver were studied by administering a model compound, lidocaine, to the isolated rat liver. Lidocaine was continuously infused into the liver until steady state was reached. Subsequent step changes in the inlet concentration were used to obtain information on rates of cellular uptake and rele...

The liver is, by nature, heterogeneous. It contains a complex vascular network for blood flow and a stationary phase consisting of enzymes within parenchymal cells. Several physiological processes, therefore, may combine to give observed ranges in drug elimination. Net changes in concentration are a consequence of a series of steps: uptake of subst...

The effects of lidocaine on hepatic enzyme activity were studied using the isolated perfused rat liver. The in vivo liver activity was examined by infusing lidocaine via the jugular vein, followed by organ isolation and drug perfusion 24 h later. The liver was studied in vitro by perfusing the organ with lidocaine until steady state was reached, th...

The steady state kinetics of lidocaine and its metabolites were modeled using nonlinear elimination pathways for multiple enzymes. The main metabolites, monoethylglycinexylidide and 3-hydroxy-lidocaine, were infused in the absence of lidocaine to measure the kinetic parameters for secondary elimination. Data from continuous perfusion of lidocaine i...

Three models for the elimination of lidocaine in the isolated perfused rat liver were used to simulate the time course of both lidocaine and its metabolites in a single-pass perfusion system: well stirred, parallel tube, and a two-compartment model to test the effects of enzyme heterogeneity. All models included multiple enzymes and multiple metabo...

The elimination of the drug lidocaine by the liver was modelled as a chemical reactor system, using data from in-vitro tests of liver metabolism. A network of reactions, based on the known metabolic pathways, was used to account for the observed concentrations of drug and reaction products in steady state. The rates of reaction were substantially h...