Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

PDF

Theses/Dissertations

Food Science

Theses and Dissertations

Salmonella

Articles 1 - 9 of 9

Full-Text Articles in Life Sciences

Food Safety Risk In An Indoor Microgreen Cultivation System, Gina Marie Misra May 2020

Food Safety Risk In An Indoor Microgreen Cultivation System, Gina Marie Misra

Theses and Dissertations

Microgreens are immature sprouts of edible plants, sharing some similarities with sprouted seeds and petite leafy greens. Since they are most often grown in containers in buildings or greenhouses, they present a new area for food safety research at the intersection of the built environment and produce farming. Contamination by human pathogens has been extensively studied in other types of produce typically eaten raw, including sprouted seeds, which have been implicated in numerous outbreaks of salmonellosis over the last several decades. There is a paucity of knowledge about the microgreen sector of the fresh-cut industry; thus, it was determined that ...


Assessment Of Salmonella Enterica Biofilms And Expression Differences Among Serovars, Zhaohao Shi Dec 2018

Assessment Of Salmonella Enterica Biofilms And Expression Differences Among Serovars, Zhaohao Shi

Theses and Dissertations

Biofilms are communities of microorganisms associated by a matrix of extracellular polymers. In this state, microorganisms occupy an ecological niche distinct from their free-floating, planktonic counterparts. Also, biofilm bacteria become biologically unique as they form communities and lose motility. The acquisition of these physiological attributes enables the biofilm to persist through harsh environmental conditions, including antimicrobial induced stress and to resist sanitization efforts. Because of these features, biofilms can rapidly disseminate across numerous surfaces and as they establish, become challenging to remove. This is a particular issue for the food industry as processing plants offer favorable conditions for biofilm formation ...


Role Of Incompatibility Group 1 (Inci1) Plasmid-Encoded Factors On Salmonella Enterica Antimicrobial Resistance And Virulence, Pravin Raghunath Kaldhone Dec 2017

Role Of Incompatibility Group 1 (Inci1) Plasmid-Encoded Factors On Salmonella Enterica Antimicrobial Resistance And Virulence, Pravin Raghunath Kaldhone

Theses and Dissertations

Foodborne illnesses are a leading cause of infectious diseases in the world. Among enteric organisms Salmonella is a key pathogen. It’s high prevalence in poultry and other food-animal sources make it imperative to study. Salmonella has the ability to modify its genetic content with help of mobile genetic elements such as plasmids. Incompatibiltiy group 1 (IncI1) plasmids are commonly reported in Salmonella. This study evaluates role on IncI1 plasmids in antimicrobial resistance and virulence in Salmonella. Genetic determinants of resistance and virulence are noted among our IncI1-containing Salmonella isolates. These genetic elements are also transferable and reported to carry ...


Experimental Approaches To Understand And Control Salmonella Infection In Poultry, Yichao Yang Dec 2017

Experimental Approaches To Understand And Control Salmonella Infection In Poultry, Yichao Yang

Theses and Dissertations

Salmonella is a major foodborne pathogen around the world and chickens are the major reservoir to transmit Salmonella into the human food chain. For decreasing the infection of Salmonella, we developed six attenuated live vaccines based on Salmonella Enteritidis (SE) and Typhimurium (ST) for testing the cross-serovar and cross-serogroup protection from the challenge of Salmonella Heidelberg and Campylobacter jejuni. One of the constructed vaccine strain showed ability to protect against challenge from Salmonella Heidelberg. Even though some preventive approaches are able to decrease Salmonella colonization in the gastrointestinal tract of chickens or other farm animals, Salmonella transmission mechanisms remain unclear ...


A Molecular Approach To Understanding The Effects Of Original-Xpc On The Modulation Of The Cecal Microbiota And The Survival Of Salmonella In The Poultry Host, Stephanie Roto May 2016

A Molecular Approach To Understanding The Effects Of Original-Xpc On The Modulation Of The Cecal Microbiota And The Survival Of Salmonella In The Poultry Host, Stephanie Roto

Theses and Dissertations

Salmonella is a foodborne pathogen commonly associated with poultry products; the economic burden to the U.S. is estimated to be approximately $693 million (without factoring in contaminated eggs). Recently, there has been pressure to withdraw sub-therapeutic levels of antibiotics (also known as antibiotic growth promoters; AGP) from poultry due to concern over antibiotic-resistant bacteria spreading to the human population. Therefore, various feed additives have been researched for their ability in providing protection against harmful pathogens and their potential growth promoting effects, both of which were attributes of poultry treated with AGP. This thesis consists of a comprehensive literature review ...


Phenotypic And Functional Genomics Analyses Of Salmonella For Food Safety Applications, Turki Dawoud May 2015

Phenotypic And Functional Genomics Analyses Of Salmonella For Food Safety Applications, Turki Dawoud

Theses and Dissertations

Non-typhoidal Salmonella species have been major foodborne zoonotic pathogens causing serious problems in public health and food industry for several decades. Numerous Salmonella species have frequently been associated with different food commodities mainly poultry meat, eggs, and their products. This dissertation begins with a literature reviews discussing many aspects of Salmonella generally; and subsequently focused on two serotypes, Salmonella Enteritidis and S. Typhimurium as they are at the top of all other serovars responsible for most illness cases and outbreaks. In addition, some Salmonella strains have exhibited their ability to tolerate and survive many food processing treatments. We can divide ...


The Effects Of Electrostatic Spraying With Organic Acids In The Disintegration Of Biofilms Formed By E.Coli O157:H7 And Salmonella Typhimurium On Spinach And Cantaloupe, Ahmad Almasoud May 2015

The Effects Of Electrostatic Spraying With Organic Acids In The Disintegration Of Biofilms Formed By E.Coli O157:H7 And Salmonella Typhimurium On Spinach And Cantaloupe, Ahmad Almasoud

Theses and Dissertations

Outbreaks from the consumption of fresh produce are a concern in the United States. The consumptions of fresh produce have increased recently which expose a large segment of society to such outbreaks. Spinach and cantaloupe are minimally heated or processed before consumption which makes them a possible source of foodborne illness. The objective of this research was to investigate the effect of organic acids alone and in combination to reduce attached Salmonella Typhimurium (S.T) and Escherichia coli O157:H7 (E.coli) on spinach and cantaloupe, and to disintegrate biofilm formed by these pathogens by electrostatically spraying with two organic ...


Phenotypic, Physiological And Growth Interactions Among Salmonella Serovars, Juliany Rivera Calo Dec 2013

Phenotypic, Physiological And Growth Interactions Among Salmonella Serovars, Juliany Rivera Calo

Theses and Dissertations

This thesis consists of four research parts: a literature review that covers Salmonella spp., one of the more prominent foodborne pathogens that represents a major risk to humans (chapter 1). Understanding the growth of Salmonella serovars and strains is an important basis for more in depth research. In this case we studied a) the aerobic and anaerobic growth responses of multiple strains from six different serovars, b) how the spent media from different serovars, more importantly S. Heidelberg, affect the growth of S. Typhimurium, and c) determined whether or not two different serovars undergo competitive interactions when they were grown ...


Electrostatic Spray Application Of Food-Grade Organic Acids And Plant Extracts To Decrease Escherichia Coli O157:H7 And Salmonella Typhimurium On Select Produce, Leighanna Maeree Massey Dec 2013

Electrostatic Spray Application Of Food-Grade Organic Acids And Plant Extracts To Decrease Escherichia Coli O157:H7 And Salmonella Typhimurium On Select Produce, Leighanna Maeree Massey

Theses and Dissertations

Both consumers and suppliers have been negatively affected by an increase in foodborne pathogens contaminating fruits. Consequently, there is a need for the development of more efficient antimicrobials and application techniques to decrease contamination. Natural preservatives such as organic acids and plant extracts have demonstrated promising results in decontaminating produce. In addition, the effectiveness of such preservatives may be enhanced by the use of an electrostatic sprayer. The objective of this research was to determine the combinations and concentrations of organic acids and plant extract that were able to reduce Salmonella Typhimurium (ST) and Escherichia coli O157:H7 (EC) inoculated ...