Life Sciences Commons^™

A Multi-State Molecular Epidemiological Survey Of 16 Beef, Dairy, Poultry And Swine Farms To Facilitate Risk Assessment Of Listeria Monocytogenes, David Dean Rasmussen

Doctoral Dissertations

Listeria monocytogenes s an intracellular pathogen that poses serious risks for immuno-compromised individuals. On the farm risk assessment is needed to reduce exposure of such individuals to this pathogen. Base line epidemiological surveys for this pathogen are needed to identify common ecological reservoirs and sources. A 21 month survey of 4 animal farm types for L. monocytogenes in five different states was conducted to determine the level of occurrence in various environments. An overall occurrence of 1.4% (20/1432 samples) for L. monocytogenes was observed in this 21 month survey. Each sample type (soil, bedding/litter, feed/grass and animal rectal swabs) produced …

Antimicrobial Activity And Effect Of Selected Essential Oil Components On Cell Membrane Lipids, Valerie W. Ling

Doctoral Dissertations

The objectives of this study were to evaluate the antimicrobial activity of essential oil components (EOC) against Salmonella Typhimurium and Listeria monocytogenes and evaluate changes in bacterial membrane composition by observing changes in the fatty acids of Salmonella associated with exposure and adaptation to (or growth in the presence of) cinnamaldehyde (CIN) and carvacrol (CRV) EOC. Ten EOC were tested for efficacy using the broth microdilution and macrodilution methods. Beta-caryophyllene, limonene, alpha-pinene, and thymol were not lethal to Salmonella and Listeria at 2800mg/L. Dose-response models showed that the most effective EOC against Salmonella were CIN and CRV (50% probability of …

Physicochemical And Antimicrobial Properties Of Antimicrobials Encapsulated In Surfactant-Based Nanoparticles, Sylvia Gaysinksy Segura

Masters Theses

Phytophenols, components of essential oil extracts, are antimicrobials that may inhibit the growth of foodborne pathogens. However, their antimicrobial activity in food systems is low because of low water solubility and association with other food components. Incorporation of phytophenols in nanoscale surfactant micelles may offer a potential solution to increase solubility and improve activity in food systems. The objectives of this study were to determine the stability and physicochemical and antimicrobial properties of micellar antimicrobial-surfactant systems.

Carvacrol and eugenol containing micelles were prepared by dispersing Surfynol^® 485W and Surfynol^® 465 in water at room temperature. Stability was determined …

Occurrence Of Escherichia Coli0157:H7 In Diverse Farm Environments In Five States, Carl Andrew Doane

Masters Theses

In the United States, foodborne outbreaks of Escherichia coli O157:H7 illness have often been linked to the consumption of contaminated, undercooked ground beef. However, the occurrence of E. coli O157:H7 in other animals has also been reported. The objective of this study was to determine the occurrence of E. coli O157:H7 in cattle, swine, poultry, and farm environments. Environmental samples (n=576) and fecal swab samples (n=1686) from sixteen locations in the U.S. were collected over 22 months. Overall, in fecal swabs E. coli O157:H7 was positive (serologically confirmed) in 4.7% of beef cattle (n = 408), 3.9% of dairy cattle …

Antimicrobial Activity Of Trypsin And Pepsin Hydrolysates Derived From Acid-Precipitated Bovine Casein, Kellie Parks Burris

Masters Theses

Foodborne pathogens are a major concern to the food industry and consumers but they may be controlled with antimicrobials. Naturally occurring antimicrobials may be isolated from a variety of plant, animal and microbial sources. Previous studies have demonstrated that peptides isolated from enzyme hydrolyzed milk proteins may have in vivo and in vitro antimicrobial activity. Such compounds could be of use as inhibitors of foodborne pathogens. The objectives of this study were to determine the antimicrobial effectiveness against Salmonella Typhimurium and Listeria monocytogenes of digests of bovine acid-precipitated casein with the enzymes pepsin and trypsin and to determine if these …

The Effects Of Selenium On Estrogen-Regulated Gene Expression In Lncap Prostate Cancer Cells, Tory L. Parker

Theses and Dissertations

Prostate cancer is the most frequently diagnosed cancer in American men and the second leading cause of cancer deaths. Supplementation with Se has reduced the incidence of prostate cancer and Se status is inversely correlated with prostate cancer risk. One molecular mechanism by which high Se concentrations may affect cancer risk is by catalyzing disulfide bond formation or otherwise complexing with reactive sulfhydryl groups in cellular proteins. The estrogen receptor (ER) contains cysteines in zinc (Zn) fingers that are susceptible to oxidation and internal disulfide formation, which can prevent DNA binding. We examined ER binding to its DNA response element …

Prevalence Of Potential Zoonotic Enteric Bacterial Pathogens In Dogs And Cats And Factors Associated With Potential Transmission Between Animals And Humans, Omaima Maamoun Ahmed

Masters Theses

With the discovery of the human immunodeficiency virus (HIV) and acquired immune deficiency syndrome (AIDS), concerns about dangers of pet ownership have increased. Zoonotic organisms associated with cats and dogs, may cause life-threatening infections in immuosuppressed human beings. The objectives of this project were to determine the prevalence of potential zoonotic enteric pathogens (Salmonella, Listeria, and Campylobacter) in feces of dogs and cats (diarrheic, healthy, and hospitalized), to evaluate the association of diarrhea in dogs and cats with diarrhea in human beings sharing the same household, and to evaluate the antimicrobial susceptibility of Salmonella, Listeria …

Atmospheric Plasma Inactivation Of Foodborne Pathogens On Fresh Produce Surfaces, Faith Michelle Johnson

Masters Theses

A study was conducted to determine the effect of a one atmosphere uniform glow discharge plasma (OAUGDP) on inactivation of nalidixic acid resistant Escherichia coli O157:H7 and Salmonella, and Listeria monocytogenes on apples, cantaloupe, and lettuce, respectively, and culture media [tryptic soy agar (TSA) + 50 ppm nalidixic acid (TSAN) for E. coli O157:H7 and Salmonella; TSA for L. monocytogenes). A mixture of cultured test organisms was washed, suspended in phosphate buffer and spot inoculated onto produce or culture media (6 log CFU/sample). Inoculated produce or culture media (samples) were exposed inside a chamber affixed to the …

Production And Characterization Of Fungal Chitin And Chitosan, Tao Wu

Masters Theses

Chitin is a biopolymer. Theoretically, it is a homopolymer of acetyl-glucosamine. Chitosan is the deacetylated product of chitin. Chitin and chitosan have many applications in water purification, agriculture, food and pharmaceutical industries. Currently, industrial production for chitin and chitosan is from the shell wastes. The objective of this study was to evaluate the feasibility of chitin and chitosan production from fungal sources.

The accumulation of chitin and chitosan during A. bisporus storage and Aspergillus niger and Mucor. rouxii. Growth was evaluated by total glucosamine determination. Chitin and chitosan were extracted from biomass by alkali and acid treatment and yield and …

Inactivation Of Escherichia Coli O157:H7 And Listeria Monocytogenes By High-Intensity Ultrasound In The Presence Of Salts, Kimberly D. Stanley

Masters Theses

Inactivation of Escherichia coli O157:H7 and Listeria monocytogenes suspended in salt solutions Na2PO4, NaCl, NaNO3, NH4Cl, CaCl2, AlCl3, and L. monocytogenes in salt solutions NaCl, NaNO3, AlCl3 at concentrations ranging from 0 to 5% (wt/vol) by high-intensity ultrasound at two different temperature conditions (ice water bath, 40ºC water bath) and three ultrasonic intensity levels (9.49, 21.83, 49.22 W/cm2) was determined. Increases in sonication treatment time, intensity and temperature led to increased lethality of both pathogens. However, cell lethality, as a function of solute concentration, varied depending upon type of salt. CaCl2, NaCl, NaNO3, NaPO4, and NH4Cl had little or no …

Molecular Weight And Degree Of Acetylation Of Ultrasonicated Chitosan, Shari Rene Baxter

Masters Theses

Chitosan is a glucosamine polymer produced by deacetylation of chitin from crustacean shells. The functional properties of chitosan, such as thickening, film-formation and antimicrobial activity, are related to its molecular weight and degree of acetylation (DA). High intensity ultrasonication has the potential to modify molecular weight of chitosan and thus alter or improve chitosan functional properties. The objective of this research was to determine the DA and molecular weight of chitosan molecules as a function of sonication intensity and treatment time.

High molecular weight shrimp chitosan was purified by alkaline precipitation and dialysis from aqueous solution. A 1 % (w/v) …

High-Intensity Ultrasound Mediated Structure-Function Changes Of Bsa As Affected By Ph, İbrahim Gülseren

Masters Theses

The influence of high intensity ultrasound on the structure-function relationship of BSA sonicated at various sonication times at neutral, acidic and basic pH was determined. Protein solutions (3 x 10^-4 M) were treated with high-intensity ultrasound at an ultrasonic intensity of 20 Wcm^-2 with treatment times ranging from 0 to 90 minutes. Changes in structure-function properties of BSA were monitored using a wide variety of biochemical and physicochemical analytical methods including interfacial tensiometry, free sulfhydryl group assays, zeta potential analysis, hydrophobicity assays, circular dichroism spectroscopy, micro DSC and FTIR. The results were attributed to mechanical and chemical changes …

Development And Characterization Of Antimicrobial Food Coatings Based On Chitosan And Essential Oils, Shuang Chi

Masters Theses

The objectives of this research were (1) to evaluate antimicrobial effects of essential oils incorporated in chitosan edible films against Listeria monocytogenes and Escherichia coli O157:H7, (2) to evaluate effectiveness of the films on a meat product, (3) to characterize physical properties of chitosan films enriched with essential oils, and (4) to determine whether the addition of oregano essential oil to bologna can influence consumer liking of the product.

Anise, basil, coriander, and oregano essential oils were tested for antimicrobial activity by paper disc diffusion test with concentration of 1 to 24 ml/disc. Chitosan films incorporated with those essential oils …

Multistate Study To Determine The Presence Of Salmonella Spp. In Farm Animals And Their Environment, Andres Rodriguez Lozano

Masters Theses

Salmonella is the second most common cause of foodborne infection in the Unites States (US). It is estimated that about 1.4 million people suffer from salmonellosis a year in the US with an estimated annual cost of $2.9 billion. Human cases of salmonellosis are often related to the consumption of raw meat and unpasteurized milk and milk products. Whereas the fecal-oral contamination is well established at farm level, less in known about the role of the environment on the Salmonella survival. The objective of this study was to compare isolation of Salmonella in farm animals and their environment based on …

The Effect Of Religiosity And Spirituality On Work Practices And Trust Levels In Managers And Their Subordinates In Food And Nutrition Care Departments, Jennifer S. Oler

Theses and Dissertations

The purpose of this study was to examine the extent to which religiosity and spirituality affected daily work practices and leader/follower trust levels in foodservice and nutrition directors and their subordinates. A similar 72-item survey questionnaire was developed for both the directors and employees, which was completed by 129 directors and 530 employees. Both questionnaires contained questions on demographics, religious influences on work practices, trust characteristics, and three validated measures of religiosity: 1) worship service attendance (1=Religiosity Score), 2) influence of spiritual beliefs on daily life, and 3) frequency of prayer (2 + 3=Spirituality Score). Frequency data was gathered for …

Body Mass Index And Soft Drink Consumption Among Adolescents, Olivia Love Mccord

Theses and Dissertations

Objective: To determine the relationship between body mass index (BMI) and soft drink consumption among adolescents. It is hypothesized that soft drink consumption contributes to overweight and obesity among adolescents.

Background: Research examining the relationship between body mass index and soft drink consumption is inconsistent. Several studies have found a negative association between total sugar intake and BMI; however, others have found a link between sugar-sweetened drinks and obesity. There are no known studies that have controlled for physical activity.

Data and Methods: Data on approximately 225 adolescents were used. Frequency of soft drink consumption, type of milk, and calcium …

Nutrition And Bone Density In Children With Cystic Fibrosis, Joanna K. Davidson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of these studies was to further research on bone density in children with cystic fibrosis, particularly as it pertains to nutritional parameters and care. The first paper presented a comparison of a group of 50 children with cystic fibrosis to a group of 32 control children. There were no significant differences between the groups in any of the pertinent bone density measurements. Serum 25(OH) vitamin D was positively correlated with spine density z score in the cystic fibrosis group.

The second paper, incorporating all of the information obtained from the first paper, describes an intervention study with the …

Cultivation Of Mushroom Mycelia Using Whey Products As A Growth Substrate, Boyd S. Inglet

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As part of a project designed to utilize common dairy waste products profitably, reconstituted dry whey permeate and delactosed whey were tested as growth substrates for mycelia of the edible mushroom Lentinus edodes. This mushroom was chosen because it is possible to profitably cultivate it due to its popular culinary appeal and perceived medical benefits.

Growth experiments were performed in petri dishes containing either reconstituted dry whey permeate or delactosed whey as a growth substrate, and the measured response was the size of the growing mycelia colony. When reconstituted dry whey permeate was utilized as a growth substrate, the …

Influence Of Sodium Chloride, Calcium, Moisture, And Ph On The Structure And Functionality Of Nonfat Directly Acidified Mozzarella Cheese, Brian M. Paulson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Experiment A explored the influence of sodium on direct acid, nonfat Mozzarella cheese. Cheeses with differing salt levels were obtained by varying dry salt applications (none, 0.5%, and 1.0% NaCl w/w) and hot brine stretching (0%, 5%, and 10% NaCl wt/v). Salt application and salt content influenced cheese moisture, meltability, expressible serum, micro- and ultra-structure, and color. Moisture was highest when cheese was salted before stretching (P = 0.03). Melt was lowest in cheeses that were unsalted (P = 0.05). Cheeses stretched in salt brine had < 1% of the amount of expressible serum found in unsalted cheese (P < 0.0001). Unsalted cheeses had a more open structure with pockets of serum distributed throughout the protein matrix giving it an opaque, white appearance. Salted cheeses had a more homogeneous protein matrix lacking light scattering surfaces, resulting in a translucent cheese. Neither salt concentration nor method of salting affected the calcium content of the cheeses (P > 0.05).

Experiment B explored the influence of calcium, moisture, and …

Comparative Effects Of Sodium Levulinate And Sodium Lactate On Microbial Growth, Color, And Thiobarbituric Acid (Tba) Values Of Fresh Pork And Turkey Sausages During Storage, Mihir N. Vasavada

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study compared the effects of 1.4 or 2.7% sodium levulinate or sodium lactate on aerobic plate count (APC), color, pH, and TBA value of fresh pork and turkey sausage. Both sodium lactate and levulinate inhibited growth of aerobic microorganisms during storage, compared to controls. Bacteriostatic effects of sodium lactate were dose dependent, wherein 2.7% lactate was significantly more antimicrobial than 1.4% lactate. This was not the case for sodium levulinate, where 1.4% sodium levulinate was as inhibitory to microbial growth as 2.7% sodium levulinate. Additionally, 1.4% sodium levulinate was as inhibitory to microbial growth as the higher level (2.7%) …

Assessment Of Calcium, Milk, And Non-Milk Beverage Intake Of Multiethnic Youth Aged 10 To 18 Years, J. Keith Jensen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Achieving and maintaining maximal peak bone mass is critical to the prevention of osteoporosis. Adequate calcium intake during youth is a major aspect of proper bone mass development. Because of the importance of calcium, a food frequency questionnaire (FFQ) that estimates calcium intake of 10- to 18-year-old Asian, Hispanic, and white youth living in the western United States was developed. This new FFQ was shown to accurately and reliably estimate calcium intake of these youth. Accuracy among Hispanics, however, was low and requires further evaluation. A second study examined intake of calcium, milk, and non-milk beverages of Hispanic and non-Hispanic …

Prevention Of Pigment Deterioration And Lipid Oxidation In Ground Beef And Pork, Preetha Jayasingh

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Fresh beef was modified-atmosphere packaged in carbon monoxide or oxygen to prolong red surface color. After comparison of several packaging method using carbon monoxide, steaks pretreated with 5% carbon monoxide for 24 hours and then vacuum packaged had the best combination of color and microbial stability (5 weeks), with the least potential for carbon monoxide inhalation.

In the evaluation of ground beef in high-oxygen, modified-atmosphere-packaging, thiobarbituric-acid numbers increased over time, and the flavor was disliked slightly after 6 or 10 days of storage at 2° Celsius.

The antioxidant effect of milk-mineral was tested in raw and cooked ground pork stored …

Effect Of Raw Lngredient Surface Area, Storage Time And Antioxidants On Color And Oxidative Stability Of Ground Beef In 80% Oxygen Modified Atmosphere Packaging, Avanthi Vissa

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Fresh beef packaged in high-oxygen modified atmosphere packaging (MAP) has longer red color stability than beef in oxygen-permeable polyvinyl chloride (PVC) film. However, fresh beef in high oxygen becomes rancid by 10 days storage at 2°C. Thus the objective of this study was to evaluate the effectiveness of various antioxidants (milk mineral, MM; sodium tripolyphosphate, STP; vitamin E, E) on color and thiobarbituric acid (TBA) values of ground chuck stored in 80% oxygen MAP for 14 days at 1° C. A preliminary experiment was also done to determine the effect of raw meat history (surface area during storage and storage …

Casein Supramolecules: Structure And Coagulation Properties, Bonney S. Oommen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The changes in quaternary structure of casein supramolecules with various physical and chemical treatments were studied using transmission electron microscopy, and a model to account for the changes is put forth. The effects of casein structure on coagulation properties were also studied. The sample preparation for transmission electron microscopy involved physical methods of fixation and flash freeing to preserve the structure of caseins in the sample.

The structure of caseins in sodium and calcium caseinate varied with sodium caseinate not exhibiting any spherical structure as opposed to the spherical structure seen in calcium caseinate, non-fat dried milk and native milk. …

Voluntary And Involuntary Weight Change And Risk Of Osteoporotic Hip Fracture In Men And Women Of Utah, Megan Ruth Mcdonough

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Change in body weight is an important determinant of risk of osteoporotic hip fracture in aging adults. Weight loss has been associated with an increased risk of hip fracture and weight gain has been associated with a decreased risk of hip fracture. Weight gain cannot be recommended as appropriate prevention against hip fracture, however, because it is associated with such adverse health outcomes as cardiovascular disease and diabetes, and weight loss is commonly recommended in the treatment of these types of diseases. Clarification of how weight loss is related to risk of hip fracture is needed to resolve this issue. …

Hormone Mediated Transport Of Calcium And Phosphate In Polarized Epithelial Cells, Tremaine M. Sterling

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effects of 1,25(OH)₂D₃, PTH and 25(OH)D₃ on phosphate or calcium uptake were studied in cultured, adherent chick enterocytes over a period of 10 min after hormone addition. Time course studies of cells treated with 130 pM 1,25(OH)₂D₃ showed an increase in ³²P uptake as early as 3 min. Similar studies with 65 pM bPTH(l1-34) resulted in an increase in ⁴⁵Ca uptake only if the cells had been cultured in serum. (OH)D₃, which is not firmly established as an active metabolite of vitamin D, was shown to increase …

Magnesium Intake And Its Relationship With Type 2 Diabetes, Caralee Wilcock

Undergraduate Honors Capstone Projects

Magnesium is an alkaline earth metal and is the second most abundant cation in the human body. Magnesium plays important roles in the structure and the function of the human body; it is involved in more than 300 essential metabolic reactions in the body. Magnesium has been implicated in the prevention and treatment of many diseases including diabetes. Magnesium depletion is commonly associated with both insulin dependent and non-insulin dependent diabetes. A significant number, (between 25% and 39%) of diabetics have been shown to have decreased serum levels of magnesium. There are many possible reasons and mechanisms for this. Diabetics …