Life Sciences Commons^™

A Comparison Of The Prevalence Of Salmonella, Specifically S. Enteritidis, In Captive Born Versus Wild Caught Reptiles, Jessica Thomas, Carrie M. Doyle

Undergraduate Theses

Salmonella contamination and transmission is a concern in public health in the United States and around the world. It is usually transmitted to humans through contaminated poultry products, but it has also been known to be transmitted through contact with reptiles. Because reptiles are becoming more popular as pets and are known carriers for Salmonella, studies have been done to test how prevalent Salmonella is in reptiles. This study focused on testing the feces of twenty-two reptiles for Salmonella, in general, and a specific serotype of Salmonella, S. Enteritidis. This study also compared the positivity rate of reptiles born …

Salmonella In The Environment: A Review On Ecology, Antimicrobial Resistance, Seafood Contaminations, And Human Health Implications, Mohammad Maruf Billah, Md Saydur Rahman

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Salmonella is a genus of Gram-negative bacteria that is responsible for numerous food poisoning outbreaks worldwide. With 93.8 million food-borne illnesses and 155,000 fatalities annually, it has emerged as a significant global public health issue. There are currently more than 2,500 distinct Salmonella serotypes, and more than half of them are associated with Salmonella enterica. An increasing global public health concern for humans and animals is antimicrobial resistance by Salmonella species worldwide. Salmonella infections can be lethal; conditioned with an increased prevalence of multi-drug resistant (MDR) strains in the future. The emergence of MDR Salmonella serotypes is considerably …

Growth Of Food-Borne Pathogens Listeria And Salmonella And Spore-Forming Paenibacillus And Bacillus In Commercial Plant-Based Milk Alternatives, Klaudia Bartula

ORBioM (Open Research BioSciences Meeting)

An increase in vegan diet preference, lactose intolerance, calorie concern and environmental awareness has led to a rise in the popularity of plant-based alternatives to bovine milk. However, there are still gaps in understanding how known bacterial food contaminants behave in plant-based beverages. The present study is the first to compare the growth of food-pathogens Listeria monocytogenes and Salmonella enterica, food spoilage Bacillus subtilis and an industrial milk product isolate, spore-forming Paenibacillus in commercially available ultrahigh temperature processed bovine milk and plant-based milk alternatives (coconut, almond, cashew). Beverage samples were inoculated with a strain cocktail or individual strains of either …

Use Of Transposon Screening For Salicylic Acid-Assisted Desiccation Killing In Salmonella, Shannon D. Elliott

Electronic Theses and Dissertations

Salmonella enterica serovar Typhimurium is one of the most prevalent food-borne pathogens, affecting millions around the world every year, making it a threat to global health. Salmonella possesses the ability to survive the normally lethal condition of desiccation, however, discovery of the genes and mechanisms behind this phenomenon are still ongoing. Using a transposon mutagenesis approach to construct a broad transposon library, this study aimed to uncover genes that may be contributing to changes in Salmonella’s survivability under desiccation, particularly when exposed to the antimicrobial molecule salicylic acid. Building on previous findings showing salicylic acid can alter cell viability …

Evaluating Salmonella Cross Contamination In Raw Chicken Thighs In Simulated Post-Chill Tanks, Raziya Sadat

Department of Food Science and Technology: Dissertations, Theses, and Student Research

Salmonella contamination poses a significant risk to food safety, particularly in poultry products and public health. This study aims to investigate the effectiveness of peracetic acid (PAA) treatment in mitigating Salmonella cross-contamination in chicken thighs within simulated post-chill tanks, considering different inoculum concentrations and organic matter (OM) levels.

The experiment involved the use of five distinct Salmonella serovars to inoculate chicken thighs, which were categorized into two groups: higher inoculation level (ca. 7 log CFU/mL) and lower inoculation level (ca, 4 log CFU/mL). These groups underwent treatment with four different solutions, including 540 ppm PAA with 1.5% OM, 540 ppm …

Microbiological Safety And Quality Of Ceviche, Poke, And Sushi Dishes Sold At Retail Outlets In Orange County, Ca, Grace E. Marquis, Samantha M. Covaia, Amanda M. Tabb, Courtney J. Kitch, Rosalee S. Hellberg

Food Science Faculty Articles and Research

Raw, ready-to-eat (RTE) seafood products, such as ceviche, poke, and sushi, have experienced growing demand globally; however, these products have the potential to be contaminated with foodborne pathogens. The objective of this study was to determine the prevalence of Escherichiacoli/coliforms, Salmonella, and Listeria in ceviche, poke, and sushi dishes sold at the retail level in Orange County, CA, USA. Additional organisms detected during testing were also considered in the results. A total of 105 raw, RTE samples of ceviche, poke, and sushi were collected from restaurants and grocery stores in Orange County, CA. Samples were tested for Salmonella …

Filth Flies As A Vector For Some Pathogenic Bacteria Transfer, Ahmet Buyukyavuz

All Dissertations

Two separate sets of experiments were conducted to determine the transfer of bacteria by flies. An Escherichia coli ampicillin-resistant strain with a fluorescent gene was used during the experiments. The first set of experiments were divided into two trials to measure the transfer of E. coli by fruit flies to apple slices and bologna during short term exposure. Short time exposure (1, 5 and 15 min) of flies to inoculated apple slices were tested in the first trial to determine the transfer of E. coli to flies. No difference (P>0.05) in the number of bacteria transferred to flies were …

A New Method For Reducing Salmonella In Poultry Meat, Regis Yizerwe

Honors Theses

An important approach to decreasing the transmission of Salmonella into the food chain is to treat raw chicken after processing. This can be, and has been done, by using antibiotics and chemical disinfectants. Using antibiotics is not a viable option due to the issue of antimicrobial resistance. Although some chemical disinfectants have been used effectively, they are restricted due to the amounts that can be used safely, the acceptance of their use and resistance to implementation in various parts of the world. This study has revealed that using a naturally occurring saponin–Quillaja Saponaria– in small concentrations under certain conditions of …

Thermal Inactivation Of Salmonella, Escherichia Coli, And Enterococcus Faecium Nrrl B-2354 In Pasta Matrices, Kristi Shannon Gowans

Theses and Dissertations

Limited data are currently available characterizing the thermal resistance of foodborne pathogens in semolina flour and intermediate pasta matrices representative of commercial conditions during mixing, extrusion, and drying. These data are essential to pasta producers seeking to be compliant with federal regulations since Salmonella spp. and Escherichia coli demonstrate survival in wheat flour and dried pasta products. This study investigated the heat resistance of Salmonella, pathogenic E. coli, and E. faecium NRRL B-2354 in raw semolina flour and partially dried pasta intermediates via thermal death time (TDT) studies. This study also assessed the appropriateness of E. faecium NRRL B-2354 as …

Use Of Organic Acid Mixtures Containing 2-Hydroxy-4-(Methylthio) Butanoic Acid (Hmtba) To Mitigate Salmonella Enterica, Shiga Toxin-Producing Escherichia Coli (Stec) And Aspergillus Flavus In Pet Food Kibbles, Aiswariya Deliephan, Janak Dhakal, Bhadriraju Subramanyam, Charles G. Aldrich

Department of Food Science and Technology: Faculty Publications

Post-processing operations of extruded pet food kibbles involve coating the product with fats and flavorings. These processes increase the risk for cross-contamination with food-borne pathogens such as Salmonella and Shiga toxin-producing Escherichia coli (STEC), and mycotoxin-producing molds such as Aspergillus spp. after the thermal kill step. In this study, the antimicrobial effects of two types of organic acid mixtures containing 2-hydroxy-4-(methylthio) butanoic acid (HMTBa), Activate DA™ and Activate US WD-MAX™, against Salmonella enterica, STEC and Aspergillus flavus when used as a coating on pet food kibbles were evaluated. Using canola oil and dry dog digest as fat and flavor …

Mitigation Of Salmonella On Food Contact Surfaces By Using Organic Acid Mixtures Containing 2-Hydroxy-4-(Methylthio) Butanoic Acid (Hmtba), Aiswariya Deliephan, Janak Dhakal, Bhadriraju Subramanyam, Charles G. Aldrich

Department of Food Science and Technology: Faculty Publications

Contaminated surfaces can transmit pathogens to food in industrial and domestic food-handling environments. Exposure to pathogens on food contact surfaces may take place via the cross-contamination of pathogens during postprocessing activities. Formaldehyde-based commercial sanitizers in recent years are less commonly being used within food manufacturing facilities due to consumer perception and labeling concerns. There is interest in investigating clean-label, food-safe components for use on food contact surfaces to mitigate contamination from pathogenic bacteria, including Salmonella. In this study, the antimicrobial effects of two types of organic acid mixtures containing 2-hydroxy-4-(methylthio) butanoic acid (HMTBa), Activate DA™ and Activate US WDMAX …

Mitigation Of Salmonella On Food Contact Surfaces By Using Organic Acid Mixtures Containing 2-Hydroxy-4-(Methylthio) Butanoic Acid (Hmtba), Aiswariya Deliephan, Janak Dhakal, Bhadriraju Subramanyam, Charles G. Aldrich

Department of Food Science and Technology: Faculty Publications

Contaminated surfaces can transmit pathogens to food in industrial and domestic food-handling environments. Exposure to pathogens on food contact surfaces may take place via the cross-contamination of pathogens during postprocessing activities. Formaldehyde-based commercial sanitizers in recent years are less commonly being used within food manufacturing facilities due to consumer perception and labeling concerns. There is interest in investigating clean-label, food-safe components for use on food contact surfaces to mitigate contamination from pathogenic bacteria, including Salmonella. In this study, the antimicrobial effects of two types of organic acid mixtures containing 2-hydroxy-4-(methylthio) butanoic acid (HMTBa), Activate DA™ and Activate US WD-MAX™, …

Whole Genome Analysis And Molecular Traceability Study Of Salmonella In Fresh Livestock And Poultry Meat, Sheng Song, Han Gao, Li Yan, Kun-Peng Guo, Hai-Yun Zhang, Fang-Bin Wang

Food and Machinery

In order to investigate the contamination status of Sal-monella in fresh pork and fresh chicken, and research its whole genome characteristics and molecular traceability, the laboratory randomly collected 24 fresh pork and 27 fresh chicken from the fresh market in Changsha, were inspected according to “National Food Safety Standard Food microbiological examination: Salmonella” GB 4789.4—2016. The results showed that in 24 randomly selected fresh pork, 20 samples were detected, with the detection rate of 83.3%; in 27 randomly selected fresh chicken, 20 samples were detected, and the detected rate is 74.1%; the total detection rate was 78.4%. The results …

Impacts Of Temperature And Salt Concentrations For Thermal Inactivation Of Salmonella In Moisture Enhanced Reconstructed Chicken Patties, Alik D. Browning

Graduate Theses, Dissertations, and Problem Reports

The purpose of this experiment is to determine the thermal kinetic parameters of Salmonella in moisture-enhanced, reconstructed ground chicken patties as affected by temperatures and salt concentrations. Salmonella is responsible for 35% of the foodborne illnesses associated with poultry products (Batz et al., 2011). Nonintact reconstructed chicken meat is mixed with brine solutions containing various salt and polyphosphate concentrations to increase water-holding capacity, decrease cooking losses, improve sensory tasting scores, and maintain the good quality of completed chicken products (Gill et al., 2004). Increasing salt concentrations within meats can increase the thermal inactivation of pathogens. In this study, Salmonella Typhimurium …

Evaluate A Mixer Of Hydrogen Peroxide And Peroxyacetic Acid To Mitigate Microbial Cross-Contamination Of Salmonella Typhimurium And The Surrogate Enterococcus Faecium During Triple-Washing Of Butternut Squash, Jesica M. Temple

Graduate Theses, Dissertations, and Problem Reports

Background: Recent foodborne illness outbreaks have been linked to fresh fruits and vegetables. For public safety, awareness of the risks of contamination from foodborne pathogens that can occur during post-harvest farming practices is essential to prevent foodborne outbreaks. Controlling the spread of foodborne pathogens on produce requires proper washing procedures, antimicrobials and doses. Given the speed and diversity of the produce being distributed, local incidents may become international emergencies. Methods: Studies were included if they assessed the efficacy of antimicrobials and various washing procedures and had to conclude the mitigation of cross-contamination of foodborne pathogens on produce grown in the …

Phenotypic And Genotypic Characterization Of Antimicrobial Resistance In Commonly Isolated Salmonella Serovars From Chickens, Seyyi̇de Sariçam İnce, Mehmet Akan

Turkish Journal of Veterinary & Animal Sciences

Salmonellosis caused by Salmonella agents is the second most common zoonotic infection in humans. In recent years, Salmonella's increasing antimicrobial resistance (AMR) has been a concern. The major transmission route of Salmonella is consumption of contaminated poultry products. Therefore, monitoring of antimicrobial resistance in chicken-originated Salmonella is critically important. This study investigated AMR in four commonly isolated Salmonella serovars from chickens, namely Salmonella Enteritidis (S. Enteritidis), Salmonella Infantis (S. Infantis), Salmonella Kentucky (S. Kentucky), and Salmonella Typhimurium (S. Typhimurium). A total of 133 isolates were examined by phenotypic and genotypic AMR characterization. Resistance to 14 different antimicrobials and eight …

Exploring The Use Of Probicon L28 And Bioplus 2b As Direct-Fed Microbials To Reduce Salmonella And Shiga Toxin-Producing Escherichia Coli In Market Pigs, Jimeng Bai, Macie E. Reeb, Mike D. Tokach, Jordan T. Gebhardt, Jason C. Woodworth, Robert D. Goodband, Joel M. Derouchey, Jessie L. Vipham, Qing Kang, John W. Schmidt, Dayna M. Brichta-Harhay, Joseph M. Bosilevac, Morgan Miller, Sara E. Gragg

Kansas Agricultural Experiment Station Research Reports

Pigs are hosts forSalmonellaand Shiga toxin-producingEscherichia coli(STEC) and these pathogens can commonly be isolated from the pig farm environment. Pigs can carry pathogens to the abattoir and contaminate pork products, posing a risk to public health. Identifying an intervention that effectively reduces pathogens in commercial pigs before harvest is imperative. Due to the need for effective pre-harvest interventions in the pig industry, the objective of this study was to investigate BIOPLUS 2B (Bacillus licheniformisandBacillus subtilis) and Probicon L28 (Lactobacillus salivariusL28) as pre-harvest interventions to reduceSalmonellaand STEC in commercial …

Antimicrobial Efficacy Of A Citric Acid/Hydrochloric Acid Blend, Peroxyacetic Acid, And Sulfuric Acid Against Salmonella On Inoculated Non-Conventional Raw Chicken Products, Emma Nakimera

Department of Food Science and Technology: Dissertations, Theses, and Student Research

The utilization of non-conventional chicken parts as human food varies widely across countries. The high prevalence of Salmonella, especially in the giblets, poses a high risk to public health. Poultry processors have implemented multiple hurdle technology to reduce this gram-negative pathogen in chicken parts. This study was conducted to evaluate the antimicrobial efficacy of a commercial blend of citric acid/ hydrochloric acid (CP), peroxyacetic acid (PAA), and sulfuric acid (SA) in reducing Salmonella inoculated on two chicken giblets: livers and hearts. Chicken hearts and livers were inoculated (6 log CFU/ml of rinsate) by individually immersing them in a cocktail …

Thermal Inactivation Kinetics Of Salmonella In Milk Powder As Impacted By Water Activity And Powder Type, Erika Litta Kadas

Graduate Theses and Dissertations

Historically, low-water activity (aw) foods (aw <0.65) were considered to be microbiologically safe for consumption. However, these foods have been implicated in outbreaks of pathogens such as Salmonella enterica, at a frequency that surely challenges this assumption of safety. Although usually implicated in outbreaks involving poultry and egg products, Salmonella spp. have frequently been the culprit in several outbreaks and recalls associated with low-water activity foods (LWAF) due to contamination resulting from the environment, animals, or even the employees during pre-or post-processing. One such LWAF that has been associated with Salmonella spp. outbreaks is milk powder. Milk powders are used in a variety of products ranging from infant formula to confectionary goods. With their widespread use, improving their safety is imperative. A key step in improving their safety is to thoroughly investigate preventive controls related to milk powder processing. The Food Safety Modernization Act (FSMA) established the Preventive Controls for Human Foods Rule, which mandates that processors design and establish a food safety plan outlining any potential hazards and the steps they will take to ensure those hazards do not compromise the safety of the product. Presently, the dairy industry does not have an established kill-step for milk powders post-spray drying. Spray drying may reduce some microbial populations, however, desiccation(e.g., spray drying) is not considered a kill-step. The work outlined in this thesis aims to assist our dairy industry partners in establishing their own thermal process for milk powders post-spray drying. Moisture sorption isotherms of two milk powders (nonfat dry milk: NFDM and a milk protein concentrate with 85% protein content: MPC-85) were determined and showcased that the temperatures at which the isotherms were determined (23, 40, or 60°C) significantly affected both the adsorption and desorption isotherms (p<0.0001) for each powder. Secondly, the thermal inactivation kinetics of Salmonella spp. in both powders were evaluated at two different water activities (0.20 and 0.30) and three temperatures (75, 80, and 85°C) to determine the effect of water activity on the thermal resistance of a cocktail of Salmonella spp. The D-values of Salmonella were heavily influenced by the thermal treatment temperature (p< 0.0001), but not the water activity (p >0.05). The overall findings contained within this thesis provide valuable information about the thermal inactivation kinetics of Salmonella spp. to our partners in the dairy industry so that they may implement an appropriate thermal process for their milk powders.

Effectiveness Of Selected Pre-Enrichment Broths For The Detection Of Salmonella Spp. In Meat Analogs, Georgia L. Sampson, Shannon B. Ruelle, Lieuchi Phan, Donna Williams-Hill, Rosalee S. Hellberg

Food Science Faculty Articles and Research

With the increasing variety of meat analog products, it is important to verify that the methods used for Salmonella detection are effective. The objective of this study was to compare the efficacy of three pre-enrichment broths for the detection of Salmonella in meat analog burgers: the currently used Bacteriological Analytical Manual (BAM) broth (lactose broth with Triton X-100, LB-T), universal pre-enrichment (UP) broth, and buffered peptone water (BPW). Five different meat analog products (coded A-E) were inoculated with Salmonella serotypes (S. Enteritidis or S. Agona) following the Food and Drug Administration Method Modification and Method Extension Criteria for Existing …

Evaluating Microbial Safety Of Food Products And Processes In Small Scale Food Services, Processors And Manufacturers, Sujan Acharya

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study evaluated microbial safety of relatively new and modified food products prepared especially by small-scale foodservice establishments and home producers. In the first part, microbial safety during fermentation at room temperature was evaluated. Chapter 3 monitored Listeria monocytogenes and Escherichia coli O157 survival during Sauerkraut’s natural fermentation. Chapter 4 evaluated the survival of acid-adapted E.coli O157 during kombucha fermentation and in kombucha-fruit blend during refrigeration. During both fermentations, the pathogens were inactivated before the recommended duration of fermentation. However, E.coli O157 introduced after fermentation survived in kombucha-fruit blends during refrigerated storage. The second part (Chapter 5) evaluated the safety …

Metaphylactic Antimicrobial Effects On Occurrences Of Antimicrobial Resistance In Salmonella Enterica, Escherichia Coli And Enterococcus Spp. Measured Longitudinally From Feedlot Arrival To Harvest In High-Risk Beef Cattle, Nathan S. Long, James E. Wells, Elaine D. Berry, Jerrad F. Legako, Dale R. Woerner, Guy H. Loneragan, Paul R. Broadway, Jeff A. Carroll, Nicole C. Burdick Sanchez, Samodha C. Fernando, Carley M. Bacon, Cory L. Helmuth, Taylor M. Smock, Jeff L. Manahan, Ashley A. Hoffman, Kristin E. Hales

Department of Animal Science: Faculty Publications

Aims: Our objective was to determine how injectable antimicrobials affected populations of Salmonella enterica, Escherichia coli and Enterococcus spp. in feedlot cattle.

Methods and Results: Two arrival date blocks of high-risk crossbred beef cattle (n = 249; mean BW = 244 kg) were randomly assigned one of four antimicrobial treatments administered on day 0: sterile saline control (CON), tulathromycin (TUL), ceftiofur (CEF) or florfenicol (FLR). Faecal samples were collected on days 0, 28, 56, 112, 182 and study end (day 252 for block 1 and day 242 for block 2). Hide swabs and subiliac …

Growth Of Foodborne Pathogens Listeria And Salmonella And Spore-Forming Paenibacillus In Commercial Plant-Based Milk Alternatives, Klaudia Bartula

ORBioM (Open Research BioSciences Meeting)

An increase in vegan diet preference, lactose intolerance, calorie concern and environmental awareness has led to a rise in the popularity of plant-based alternatives to bovine milk. Non-dairy products are a fast-growing food industry sector; however, there are still gaps in understanding how the known bacterial food contaminants behave in plant-based beverages. The present study is the first to compare the growth of food-pathogens Listeria monocytogenes and Salmonella enterica and an industrial milk product isolate, spore-forming Paenibacillus, in commercially available ultrahigh temperature processed (UHT) bovine milk and plant-based milk alternatives (coconut, almond, cashew). Beverage samples were inoculated with a strain …

Isothermal Inactivation Studies Of Listeria Monocytogenes, Salmonella, And Enterococcus Faecium Nrrl B-2354 In Almond, Peanut, And Sunflower Butters, Ruo Fen Liao

Theses and Dissertations

Vegetative, non-sporeforming foodborne pathogens show notable survival and uncanny thermotolerance in low water activity (aw) foods. Controlled studies on Listeria monocytogenes, Salmonella spp., and Enterococcus faecium NRRL B-2354 (a Salmonella surrogate) in a variety of food matrices support thermal process validation studies required to achieve global food safety objectives. In this study, we determined and compared thermal inactivation rates using independent six-strain cocktails of pathogens in three plant-based butters. Direct determinations of decimal reduction times (D-values) for L. monocytogenes, Salmonella, and E. faecium, in corresponding butters were inoculated using peanut oil, almond oil, or sunflower oil. Thermal Death Time (TDT) …

Resolving The Repression Pathway Of Virulence Gene Hila In Salmonella, Alexandra King, Lon Chubiz Phd, Brenda Pratte, Lauren Daugherty

Undergraduate Research Symposium

Salmonella is a relatively abundant, virulent species of bacteria that is most known for spreading gastrointestinal diseases through food. These illnesses result in approximately 1.35 million infections, including over 25,000 hospitalizations each year, in the U.S. alone (CDC.gov). As antibiotic resistance becomes an increasingly urgent public health problem, the importance of developing alternative treatment methods is only becoming more crucial. One of the genes responsible for this virulence is known as hilA. HilA is the main transcriptional regulator of Salmonella Pathogenicity Island-1 gene (UniProt). SPI-1 plays an important role in the invasion of Salmonella into epithelial cells. The proteins encoded …

To The Window, To The Wall: Improving Environmental Monitoring Protocols, Sarah Jones

Graduate Theses and Dissertations

Detecting microorganisms on environmental surfaces via an environmental monitoring (EM) program is part of a preventive food safety culture. Environmental monitoring should 1) verify that food safety plans are reducing cross-contamination risk from surfaces to food, 2) pinpoint microbial niches, and 3) prevent the transmission of pathogens. Environmental monitoring programs utilize EM tools, such as sponges, to sample food contact and non-food contact surfaces. However, EM tool selection is determined by the individual food firm. This dissertation evaluated and characterized factors influencing EM program effectiveness in the food industry. Specifically, this dissertation focuses on the release of microorganisms from EM …

Evaluation Of The Effect Of A Lippia Organoides Essential Oil Extract On Clostridium Perfringens Proliferation In Vitro And Necrotic Enteritis In Broiler Chickens, Makenly E. Coles

Graduate Theses and Dissertations

The purpose of the present research was to assess the effects of essential oils derived from the plant Lippia organoides on performance parameters, intestinal integrity, and necrotic enteritis (NE) in broiler chickens. To do this, a previously established challenge model for NE was utilized which included challenging with Salmonella Typhimurium on day 0, Eimeria maxima on day 18, and Clostridium perfringens on days 22 and 23. Treatment groups included a 1) non-challenged, negative control, 2) challenged control, and 3) challenged, Lippia origanoides (37ppm in the diet). Group 1 (negative control) had significantly (P < 0.05) higher body weight gain from d8-25 and d0-25 compared to both challenged groups. Feed intake was significantly different for all three groups (P < 0.05) at 8-25 days and 0-25 days with group 1 having the highest feed intake for both time periods. Total mortality was greater in the positive control when compared to both the negative and treatment groups. NE lesion scores were significantly different between all groups with the positive control having the highest mean lesion scores and the negative control having a mean lesion score of 0. The positive control group had the highest FITC-d amounts detected in the sera, being statistically higher than both the treatment group and negative group which were both statistically different from each other. At the present inclusion rate for the essential oil (37 ppm), there was an overall reduction in the negative impact from the NE infection. Further studies should be conducted to reach more significant conclusions.

Inactivation Of Salmonella In Black Peppercorn By Fluidization With Hydrogen Peroxide Vapor, Edel Summers

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

The purpose of the present study was to assess the effectiveness of hydrogen peroxide vapor (HPV) at inactivating Salmonella inoculated in whole black pepper when used as fluidizing gas media. HPV treatment was conducted at two different temperatures (45°C and 60°C) and two dwell times (30 min and 60 min). Microbial reduction and residual hydrogen peroxide were measured at three storage times: 0 h (immediately after treatment), 24 h and 48 h post-treatment. The effect of HPV on the quality of whole black peppercorn was evaluated 48 h post-treatment based on changes in piperine content, total phenolics, antioxidant activity, total …

The Role Of Stm1987 And Arti In Arginine Response Of Salmonella Typhimurium, Deeba Mohseni

Undergraduate Honors Theses

Cyclic-di-GMP, a common bacterial second messenger, has been thought to help develop virulence and biofilms in bacteria, most specifically in Salmonella Typhimurium. By being able to dysregulate cyclic-di-GMP production, virulence may be better combatted. STM1987, an L-arginine-responsive diguanylate cyclase with a periplasmic sensory domain, dimerizes and generates the bacterial second messenger cyclic-di-GMP in response to the amino acid L-arginine in a pathway that also requires the periplasmic L-arginine-binding protein ArtI. Their biochemical responses to L-arginine and when they dimerize could help clarify this pathway, so I sought to develop a periplasmic dimerization sensor to better monitor these biochemical interactions. Similar …

Evaluating The Microbial Quality And Use Of Antimicrobials In Raw Pet Foods, Leslie Pearl Cancio

Department of Food Science and Technology: Dissertations, Theses, and Student Research

Raw meat-based diets (RMBDs) are emerging pet foods that pose food safety risks because of the potential presence of pathogens that could cause illness to humans. In this research, the microbial quality of select RMBD products sold by pet food companies online and the use of chemical antimicrobials to reduce the microbial load in chicken liver, a common RMBD ingredient, were evaluated.

Ground meat blends and livers from four animal species (beef, pork, chicken, turkey) were purchased from four online companies that delivers directly to consumers through parcel businesses. Products were procured at three different times during one year and …