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Cytochrome P450 Monooxygenase-Mediated Lipid Metabolism In Obesity And Colon Tumorigenesis, Weicang Wang Oct 2019

Cytochrome P450 Monooxygenase-Mediated Lipid Metabolism In Obesity And Colon Tumorigenesis, Weicang Wang

Doctoral Dissertations

Colon cancer is a major public health issue: it is expected to have 140,250 new cases and 50,630 deaths during 2018, making colon cancer the third most common type of cancer and the second leading cause of cancer death in the United States. Obesity is associated with enhanced colonic inflammation, which is a major risk factor of colorectal cancer. Currently, more than 35% of adults and nearly 17% of children are obese. Considering the obesity and colon cancer epidemic in the United States, there is an urgent need to identify novel therapeutic targets for obesity and colon cancer ...


Silver Mirror Substrate And Rolling Method For Improved Surface-Enhanced Raman Spesctroscopic Analysis In Food, Yanqi Qu Oct 2019

Silver Mirror Substrate And Rolling Method For Improved Surface-Enhanced Raman Spesctroscopic Analysis In Food, Yanqi Qu

Doctoral Dissertations

Surface-enhanced Raman spectroscopy, short for SERS, is an emerging technology with great potential in food analysis due to rapid detection, high sensitivity, portable instrumentation, and simple sample preparation. However, it is always a bottleneck to obtain reproducible SERS measurements in real analytical cases due to the complicity of food systems and inhomogeneous aggregation of colloidal nanoparticles. To improve its performance for practical applications in food analysis, efforts have been made in improving the reproducibility, enhancing the selectivity and reducing the matrix interference to the analyte. Herein, a self-assembly silver nanoparticles mirror substrate was fabricated to improve the and the quantitative ...


Optical Meets Mechanical: Use Of Luminescence Spectroscopy To Assess Ageing In Biodegradable Films, Louis Colaruotolo Oct 2019

Optical Meets Mechanical: Use Of Luminescence Spectroscopy To Assess Ageing In Biodegradable Films, Louis Colaruotolo

Masters Theses

With the growing concern of the accumulation of plastic-based food packaging waste, the search for bio-based biodegradable packages is on the rise. These materials differ from their petro-based counterparts in their degradation rates, which are much higher in the former. Not only do bio-based biodegradable materials degrade faster during post-usage processes but also they age faster during usage and storage, which affects their performance and functionality. The application of noninvasive testing methods with the capability to report on the matrix’s state could assist in the development of a more ubiquitous way to assess ageing in food packaging, particularly in ...


Determining Kinetic Parameters Of Thiamine Degradation In Three Nasa Spaceflight Foods In Thermal Processing And Long-Term Storage And Methods For Analyzing Microstructure And Precipitant Development In Real And Model Wines, Timothy R. Goulette Jul 2019

Determining Kinetic Parameters Of Thiamine Degradation In Three Nasa Spaceflight Foods In Thermal Processing And Long-Term Storage And Methods For Analyzing Microstructure And Precipitant Development In Real And Model Wines, Timothy R. Goulette

Doctoral Dissertations

The current NASA spaceflight food program encompasses a wide variety of commercial and custom-made edible products. These foods are designed to ensure each crewmember receives the Recommended Dietary Allowance (RDA) of vitamins and minerals to maintain adequate health during the entire spaceflight mission. With the desire for long-duration and exploration-class missions, such as the impending mission to Mars, the retention of important nutrients such as labile vitamins in spaceflight foods is critically important. For this reason, multiple studies were conducted to determine the vitamin degradation behavior of thiamine (vitamin B1) within three spaceflight foods which demonstrated both significant presence ...


Hybridized Polymeric Nano-Assemblies: Key Insights Into Addressing Mdr Infections, Ryan Landis Mar 2019

Hybridized Polymeric Nano-Assemblies: Key Insights Into Addressing Mdr Infections, Ryan Landis

Doctoral Dissertations

Multidrug-resistant (MDR) bacteria contribute to more than 700,000 annual deaths world-wide. Millions more suffer from limb amputations or face high healthcare treatment costs where prolonged and costly therapeutic regimens are used to counter MDR infections. While there is an international push to develop novel and more powerful antimicrobials to address the impending threat, one particularly interesting approach that has re-emerged are essential oils, phytochemical extracts derived from plant sources. While their antimicrobial activity demonstrates a promising avenue, their stability in aqueous media, limits their practical use in or on mammals. Inspired by the versatility of polymer nanotechnology and the ...


Development And Application Of A Sers Needle For One-Step Multi-Phase Analysis, Haoxin Chen Oct 2018

Development And Application Of A Sers Needle For One-Step Multi-Phase Analysis, Haoxin Chen

Masters Theses

Surface-enhanced Raman spectroscopy (SERS) is an emerging and sensitive technique in food analysis providing advantages of rapid detection, simple sample preparation and on-site detection capability over GC and LC methods. Most SERS applications focus on detecting trace amount of analyte in liquid as an alternative approach to HPLC. Herein, we invented an innovative SERS-active needle which is composed with an injection needle and a gold-nanoparticles coated fiber inside the injection needle. The gold nanoparticles-coated fiber was fabricated by reducing gold (III) on a chemically etched stainless wire. The SERS needle can be used to insert into the headspace and liquid ...


Adding Increased Value To Strawberry Puree By Adding Xylo-Oligosaccharides To Improve Health, Haochen Dai Oct 2018

Adding Increased Value To Strawberry Puree By Adding Xylo-Oligosaccharides To Improve Health, Haochen Dai

Masters Theses

Cancer is a global risk for human wellness and health. Dietary habits could profoundly affect the risk of certain cancer, such as colorectal cancer (CRC) (Platz, 2000). CRC has listed the third leading cancer among male and female in the United States (Stewart, 2014). Surprisingly, the consumption of dietary fiber has an inverse correlation with the mortality of CRC (Song, 2018). However, most Americans do not consume enough dietary fiber to meet the recommended level of dietary fiber intake (Clemens, 2012; Lee-Kwan, 2017). Hence, it is reasonable to increase the nutrient density, i.e., dietary fiber, of current food model ...


In Situ And Real-Time Monitoring And Characterization Of Pesticide Residues On And In Fresh Produce Using Sers, Tianxi Yang Jul 2018

In Situ And Real-Time Monitoring And Characterization Of Pesticide Residues On And In Fresh Produce Using Sers, Tianxi Yang

Doctoral Dissertations

Understanding of the behavior and fate of pesticides in fresh produce is of great significance for effectively applying pesticides and minimizing pesticide residues in food. There is lack, however, of an effective method that can monitor and characterize pesticide behaviors including penetration, persistence and translocation. Herein, we developed a novel method for real-time and in situ monitoring of pesticide behaviors in fresh produce based on surface-enhanced Raman scattering (SERS) mapping method. Taking advantage of penetrative gold nanoparticles as probes to enhance the internalized pesticide signals, the internal signals from pesticides were successfully obtained in situ. We found that systemic pesticides ...


Development Of Methodology For Rapid Bacterial Detection In Complex Matrices Using Sers, Madeline Tucker Jul 2018

Development Of Methodology For Rapid Bacterial Detection In Complex Matrices Using Sers, Madeline Tucker

Masters Theses

Fresh foods, including meats and produce are the fastest growing market in the supermarket and the class of foods most likely to cause a bacterial foodborne illness. As the rate of consumption of perishable products increases, rapid detection of pathogens within the food supply becomes a critical issue. Current methods used for the detection of bacteria that cause food-borne illnesses are time consuming, expensive and often require selective enrichment. In this study we adapted a separation technique originally developed for PCR to extract bacteria from ground beef using β-cyclodextrin (β-CD) and milk protein coated activated carbon (MP-CAC) as filtration agents ...


Reactive Carbonyl Compounds: Their Control And Consequences In Foods, Michael Freund Jul 2018

Reactive Carbonyl Compounds: Their Control And Consequences In Foods, Michael Freund

Masters Theses

Polyunsaturated omega-3 fatty acids (n-3 PUFAs) have been suggested to reduce risk for multiple diseases but animal studies on the beneficial effects of n-3 PUFAs are conflicting, possibly due to the presence of toxic lipid oxidation products in the oils used in these studies. In order to provide guidance for future research in n-3 PUFA supplementation, this study researched lipid oxidation and its inhibition in an animal feed system enriched with fish oil. Different storage conditions were tested, and it was found that samples stored at room temperature or above were at significant risk for oxidation with lag phases of ...


Utilization Of Modified Lecithin To Control Lipid Oxidation In Bulk Oils, Anuj Shanbhag Mar 2018

Utilization Of Modified Lecithin To Control Lipid Oxidation In Bulk Oils, Anuj Shanbhag

Masters Theses

Lipid oxidation is a major challenge faced by the food industry since it causes loss of quality in lipid containing foods which results in a decrease of shelf life. In order to delay the oxidation in lipids, food industries make use of antioxidants such as EDTA (ethylene diamine tetraacetic acid), BHA (tbutyl-4-hydroxyanisole), BHT (t-butyl-4-hydroxytoluene), and TBHQ (tert-butyl-hydroxyquinone). However, these antioxidants are chemically synthesized and consumers desire simpler and cleaner labels without artificially synthesized antioxidants. Also, artificially synthesized antioxidants such as t-butyl-4-hydroxyanisole (BHA) can cause cancer in humans. Previous studies have shown that phospholipids such as phosphatidylethanolamine (PE) and phosphatidylcholine (PC ...


Tocopherol Regeneration By Phospholipids In Soybean Oil-In-Water Emulsions: Effect Of Tocopherol Homologue And Emulsifier Type, Gautam Samdani Mar 2018

Tocopherol Regeneration By Phospholipids In Soybean Oil-In-Water Emulsions: Effect Of Tocopherol Homologue And Emulsifier Type, Gautam Samdani

Masters Theses

Phospholipids can regenerate oxidized tocopherols and help delay lipid oxidation. The impact of emulsifier type, tocopherol homologue and phospholipid head group on tocopherol-phospholipid interaction was investigated in this study.

Three µmol tocopherol/kg emulsion and 15.0µmol/kg emulsion of PE or PS were dissolved in oil and emulsions were prepared. Tween 20 or bovine serum albumin(BSA) was used as emulsifier and the continuous phase contained 10mM imidazole/acetate buffer at pH 7. Lipid hydroperoxides and hexanal were measured as lipid oxidation products and the lag phase was determined. With Tween 20 as the emulsifier, α and δ-tocopherol had ...


Effects Of Solid Fat Content, Synthetic Antioxidants And Headspace Oxygen Reduction On The Rates Of Oxidation In Surface And Total Lipids Of Crackers, Collin Alexander Hayes Mar 2018

Effects Of Solid Fat Content, Synthetic Antioxidants And Headspace Oxygen Reduction On The Rates Of Oxidation In Surface And Total Lipids Of Crackers, Collin Alexander Hayes

Masters Theses

Unsaturated fats undergo a process known as oxidation by which they are degraded into undesirable compounds. Therefore it is important for food manufacturers to employ antioxidant strategies. Crackers were used as a model in these studies because of their dietary contribution to saturated, and because the properties of crackers are translatable to other low moisture foods.

The objective of this thesis was to determine if there was a significant variance in rates of oxidation between surface and total lipids in crackers and how solid fat content, synthetic antioxidants, and reduction of headspace oxygen affect those rates. It was hypothesized that ...


Use Of Different Ripening Inhibitors To Enhance Antimicrobial Activity Of Essential Oil Nanoemulsion, Victor Ryu Oct 2017

Use Of Different Ripening Inhibitors To Enhance Antimicrobial Activity Of Essential Oil Nanoemulsion, Victor Ryu

Masters Theses

The objective of this research was to study the impact of ripening inhibitor level and type on the formation, stability, and activity of antimicrobial thyme oil nanoemulsions formed by spontaneous emulsification. Oil-in-water antimicrobial nanoemulsions (10 wt%) were formed by titrating a mixture of essential oil, ripening inhibitor, and surfactant (Tween 80) into 5mM sodium citrate buffer (pH 3.5). Stable nanoemulsions containing small droplets (d < 70 nm) were formed. The antimicrobial activity of the nanoemulsions decreased with increasing ripening inhibitor concentration, which was attributed to a reduction in the amount of hydrophobic antimicrobial constituents transferred to the separated hydrophobic domain, mimicking bacterial cell membranes, by using dialysis and chromatography. The antimicrobial activity of the nanoemulsions also depended on the nature of the ripening inhibitor used: palm ≈ corn > canola > coconut which also depended on their ability to transfer hydrophobic antimicrobial constituents to the separated hydrophobic domain.


Methylglyoxal Influences Development Of Caenorhabditis Elegans Via Heterochronic Pathway, Jiaying Wang Jul 2017

Methylglyoxal Influences Development Of Caenorhabditis Elegans Via Heterochronic Pathway, Jiaying Wang

Masters Theses

Methylglyoxal is a highly reactive dicarbonyl compound, which is widely distributed in food products and beverages, and is particularly high in Manuka honey. In addition to its antibacterial effects, methylglyoxal is also known as a major precursor of advanced glycation end products (AGEs), that produces altered macromolecules (such as proteins and DNA), leading to abnormal physiological changes. However, the effects of methylglyoxal on development is unclear. Thus, this study aimed to determine the role of methylglyoxal in this aspect using Caenorhabditis elegans (C. elegans). Treatment of methylglyoxal at 0.1 mM and 1 mM for 48 h significantly inhibited development ...


Epigallocatechin-3-Gallate Reduces Fat Accumulation In Caenorhabditis Elegans, Jinning Liu Jul 2017

Epigallocatechin-3-Gallate Reduces Fat Accumulation In Caenorhabditis Elegans, Jinning Liu

Masters Theses

Epigallocatechin gallate (EGCG), also known as epigallocatechin-3-gallate, is a polyphenol that is most abundant in tea. It has been shown from many studies that consumption of EGCG can contribute to weight loss, however, the underlying mechanism is not fully understood. To determine how EGCG acts to reduce fat, an organism model Caenorhabditis elegans (C. elegans) is introduced, which is a useful animal system in exploring crucial biological mechanisms that are readily applicable to humans. In this study, different strains were raised for two days on a diet with or without 100µM and 200µM EGCG treatment: N2 (i.e., wild type ...


Understanding The Impact Of Oxygen Concentration And Active Packaging On Controlling Lipid Oxidation In Oil-In-Water Emulsions, David Johnson Jul 2017

Understanding The Impact Of Oxygen Concentration And Active Packaging On Controlling Lipid Oxidation In Oil-In-Water Emulsions, David Johnson

Doctoral Dissertations

Consumer concern over synthetic food antioxidants have led researchers to seek alternative natural, or ‘clean’ label, solutions to prevent lipid oxidation. Unfortunately, natural antioxidants are often not as effective as their synthetic counterparts. As a result, there remains a need to develop active packaging strategies and maximize current antioxidant strategies in food applications.

Active packaging, or packaging that has a function beyond being an inert barrier, is an attractive strategy to limit lipid oxidation in foods. Active packaging performs the work of an antioxidant without appearing on the package label. The work presented here builds upon active packaging development as ...


Sodium Reduction In Turkey Breast Meat By Using Sodium Anion Species, Janamkumar Pandya Mar 2017

Sodium Reduction In Turkey Breast Meat By Using Sodium Anion Species, Janamkumar Pandya

Masters Theses

Research studies show that an average American consumes 3,400 to 4,500 mg/day of sodium in their diet against the dietary recommendation of 1,500 to 2,300 mg/day. The majority of this sodium comes from processed foods. Excess sodium in the diet can potentially cause health issues such as hypertension, heart attack, kidney failure, and bone problems. The objective of this study is to understand sodium diffusion in a protein model using turkey breast meat and determine the opportunities of its reduction by changing the process conditions and combining table salt with other sodium salts.

Since ...


Label-Free And Aptamer-Based Surface Enhanced Raman Spectroscopy For Detection Of Food Contaminants, Shintaro Pang Nov 2016

Label-Free And Aptamer-Based Surface Enhanced Raman Spectroscopy For Detection Of Food Contaminants, Shintaro Pang

Doctoral Dissertations

The development of analytical methods to detect food contaminants is a critical step for improving food safety. Surface enhanced Raman spectroscopy (SERS) is an emerging detection technology that has the potential to rapidly, accurately and sensitively detect a wide variety of food contaminants. However, SERS detection becomes a challenge in real complex matrix, such as food, since non-specific matrix signals have the potential to drown out target associated Raman peaks. In this dissertation, we focused on the development and application of label-free, aptamer-based SERS in order to improve the accuracy and specificity of target contaminant detection in food. To accomplish ...


Investigate The Interactions Between Silver Nanoparticles And Spinach Leaf By Surface Enhanced Raman Spectroscopic Mapping, Zhiyun Zhang Nov 2016

Investigate The Interactions Between Silver Nanoparticles And Spinach Leaf By Surface Enhanced Raman Spectroscopic Mapping, Zhiyun Zhang

Masters Theses

Owing to their increasing application and potential toxicity, engineered nanoparticles (ENPs) have been considered as a potential agricultural contaminant that may pose unknown risk to human beings. However, many techniques require invasive and complicated sample preparation procedures to detect and characterize engineered nanomaterials in complex matrices. In the first part of this thesis, we present a non-destructive and label-free approach based on surface enhanced Raman spectroscopic (SERS) mapping technique to qualitatively detect and characterize gold nanoparticles (AuNPs), on and in spinach leaves in situ. We were able to detect the clearly enhanced signals from AuNPs at 15 to 125 nm ...


Utilizing Nutritive Sweeteners To Control Lipid Oxidation In Low Moisture Baked Goods, Samantha Vieira Nov 2016

Utilizing Nutritive Sweeteners To Control Lipid Oxidation In Low Moisture Baked Goods, Samantha Vieira

Masters Theses

In this study, we determined the effect of nutritive sweeteners at 0 to 0.50 moles/kg on lipid oxidation in a model cookie system. Confocal microscopy using Bodipy 493 as a fat soluble dye showed that the fat formed a continuous phase surrounding the starch granules regardless of sugar type. The impact of glucose concentration on lipid oxidation was monitored by lipid hydroperoxides and headspace hexanal during storage at 55°C. Low concentrations of glucose (0.09) were strong inhibitors. At equal molar concentrations, reducing sugars (glucose and fructose) inhibited lipid oxidation, greater than a two months increase in ...


Enzyme Stabilization In Hierarchical Biocatalytic Food Packaging And Processing Materials, Dana Erin Wong Jul 2016

Enzyme Stabilization In Hierarchical Biocatalytic Food Packaging And Processing Materials, Dana Erin Wong

Doctoral Dissertations

The partnership of biocatalysts and solid support materials provides many opportunities for bioactive packaging and bioprocessing aids beneficial to the agricultural and food industries. Biocatalysis, or reactions modulated by enzymes, allows bioactive materials to assist in bringing a substrate to product. Enzymes are proteins which catalyze reactions by lowering the activation energy required to drive the production of a desired product. Enzymes are commonly utilized in food processing as catalysts with specificity in order to enhance product quality through the production of beneficial food components, and to break down undesirable components that may be harmful or may decrease product quality ...


Optimization Of The Fabrication, Stability, And Performance Of Food Grade Nanoemulsions With Low And High Energy Methods, Jennifer Komaiko Mar 2016

Optimization Of The Fabrication, Stability, And Performance Of Food Grade Nanoemulsions With Low And High Energy Methods, Jennifer Komaiko

Doctoral Dissertations

There is interest in the production of emulsions by low-energy methods because no expensive equipment is required thus making emulsion formation inexpensive and simple to implement. The goal of this research is to establish the major factors that affect emulsion formation using low-energy methods and possible applications of the emulsions and nanoemulsions formed by this method. Lastly, the use of natural emulsifiers with low- and high-energy methods was investigated.

Initially, formation of nanoemulsions using isothermal low energy methods was investigated with a model system (hexadecane, Brij 30). Preliminary experiments showed that nanoemulsions could only be formed when the surfactant was ...


Fish Oil Nanoemulsions: Optimization Of Physical And Chemical Stability For Food System Applications, Rebecca M. Walker Feb 2016

Fish Oil Nanoemulsions: Optimization Of Physical And Chemical Stability For Food System Applications, Rebecca M. Walker

Masters Theses

Emulsion-based delivery systems offer many potential benefits for incorporating omega-3 oils into foods and beverages. Nanoemulsions are emulsion-based delivery systems that are gaining popularity because of their ease of preparation, small particle size, relatively high stability, high bioavailability, and production of optically transparent emulsions. Fish oil (FO) nanoemulsions are potentially more susceptible to lipid oxidation because of their high degree of lipid unsaturation, high surface area of exposed lipids, and greater light penetration. In the first study, spontaneous emulsification, a low-energy method, was used to fabricate FO nanoemulsions. The influence of surfactant-to-oil-ratio (SOR) on particle size, turbidity, and physical stability ...


Biotransformation Of Polymethoxyflavones By Gut Microbiome And Molecular Characterization Of Polymethoxyflavones By Surface Enhanced Raman Spectroscopy, Changchu Ma Nov 2015

Biotransformation Of Polymethoxyflavones By Gut Microbiome And Molecular Characterization Of Polymethoxyflavones By Surface Enhanced Raman Spectroscopy, Changchu Ma

Doctoral Dissertations

Polymethoxyflavones (PMFs), a unique class of flavonoids found in citrus fruits has shown beneficial bioactivities. Biological fate of PMFs in the gastrointestinal tract is critical for their bioactivities. PMFs can be biotransformed to produce various metabolites with different bioactivities, and PMFs can also interact with the food matrix, which in turn affects their bioactivities. Therefore, we investigated the biotransformation of two PMFs, namely nobiletin (NBT) and 5-hydroxylnobiletin (5HN) by the gut microbiome. Mice were fed with NBT or 5HN, and small intestinal contents were collected and subjected to anaerobic fermentation by gut microbiome isolated from mice and human volunteers. HPLC ...


Fabrication, Characterization And Biological Fate Of Phytochemical Delivery System, Jingjing Chen Nov 2015

Fabrication, Characterization And Biological Fate Of Phytochemical Delivery System, Jingjing Chen

Doctoral Dissertations

Polymethoxyflvones (PMFs) are a group compounds with promising cancer preventing activities and many other health benefits. There's a growing interest in fabricating delivery systems for PMFs as well as other phytochemicals due to their low water solubility. Firstly, we use nanoemulsion delivery system to encapsulate β-carotene. Sonication assisted method was developed to dissolve β-carotene to ensure minimum degradation. Powdered nanoemulsion was obtained after spray dry and freeze dry. Sample obtained after freeze dry showed better physiochemical characteristics. Then we use protein nanoparticle delivery system to encapsulate PMFS. The nanoparticle delivery system was fabricated by mixing the aqueous phase ...


Pro- And Antioxidant Effects Of Phospholipids On Lipid Oxidation In Bulk Oil, Leqi Cui Nov 2015

Pro- And Antioxidant Effects Of Phospholipids On Lipid Oxidation In Bulk Oil, Leqi Cui

Doctoral Dissertations

The aim of this thesis is to explore how phospholipids at concentrations similar as in refined vegetable oils impact bulk oil lipid oxidation. The possible formation of association colloids and synergism with primary antioxidants are considered. The results provided a better understanding of the pro- and antioxidant activities of phospholipids.

Lipid oxidation leads to quality deterioration by generating off-flavor, nutrient loss, color alteration, texture changes, and even generation of potential toxic products. Phospholipids are important minor components in edible oil that play a role in lipid oxidation. Surface active phospholipids have an intermediate hydrophilic–lipophilic balance value, which allows them ...


Structural Design Approaches For Creation Of Reduced Fat Products, Bicheng Wu Nov 2015

Structural Design Approaches For Creation Of Reduced Fat Products, Bicheng Wu

Doctoral Dissertations

In awake of the health issues related with high-calorie diet, there was a strong focus in the development of reduced-fat products in the food industry. However, fat plays an important role in determining the quality attributes of food products such as texture, appearance, flavor and stability, therefore there has been limited success for reduced-fat products. This thesis project thus targeted liquid and semi-solid products such as dressings, sauces, and aimed to address problems associated with low-fat by utilizing structural designed approach.

The first part of this project focused on using controlled aggregation of protein-stabilized lipid droplets to regulate the microstructure ...


Physicochemical And Toxicological Assessment Of Antimicrobial Ε-Polylysine-Pectin Complexes, Cynthia L. Lopez Pena Aug 2015

Physicochemical And Toxicological Assessment Of Antimicrobial Ε-Polylysine-Pectin Complexes, Cynthia L. Lopez Pena

Doctoral Dissertations

ε-Polylysine is an appealing FDA-approved, all natural antimicrobial biopolymer effective against a wide range of microorganisms. Its implementation is greatly limited by its strong cationic charge, which has been linked to instability in food systems, perceived astringency and bitterness, and the ability to inhibit lipid digestion. Previous studies have shown that controlled complexation of ε-polylysine with anionic pectin is able to prevent instability and astringency in simplified model food systems, while maintaining the antimicrobial character of polylysine. Isothermal titration calorimetry, micro-electrophoresis, microscopy, and turbidity analyses of the stability of electrostatic pectin-polylysine complexes in the presence of strongly anionic κ-carrageenan, and ...


Spray Fabrication Of Layer-By-Layer Antimicrobial N-Halamine Coatings, Anna Denis-Rohr Jul 2015

Spray Fabrication Of Layer-By-Layer Antimicrobial N-Halamine Coatings, Anna Denis-Rohr

Masters Theses

Antimicrobial coatings in which the active agent (e.g. N-halamine) can regenerate activity represent a promising way to prevent microbial cross-contamination. A reported method for applying coatings containing antimicrobial N-halamines is layer-by-layer (LbL) application of polyelectrolytes, which form N-halamines upon cross-linking. Prior reports on dip layer-by-layer (LbL) fabrication have demonstrated the potential of this coating technology; however, spray LbL fabrication would enable more rapid coating and represents a more commercially translatable application technique. In this work, dip and spray LbL methods were used to coat polypropylene (PP) with N-halamine containing bilayers consisting of cross-linked polyethylenimine (PEI) and poly(acrylic acid ...