Life Sciences Commons^™

Applications Of Drosophila Melanogaster In Food Science Research, Phoebe Beverly Chen

Doctoral Dissertations

Drosophila melanogaster is a versatile model organism that provides several unique features, such as highly conserved disease pathways with humans as well as availability of environmental and genetic manipulations. Meanwhile, there is increasing interest in the potential role of bioactive food components, epigallocatechin gallate (EGCG) and conjugated linoleic acid (CLA), in metabolic research. However, there is limited knowledge on the sex-dependent effects of EGCG and CLA on energy metabolism. In this study, Drosophila melanogaster was used to investigate the sex-dependent effects of EGCG and CLA with respect to energy metabolism, including body fat, locomotion, and their key metabolic regulators. We …

Modulation Of Hepatic Lipid Metabolism By Insecticides And Food Bioactives, Jason Yang

Doctoral Dissertations

Recent studies reported the positive association between exposure to insecticides and increased risks of obesity and type 2 diabetes, which is closely associated with non- alcoholic fatty liver disease (NAFLD). However, the effect of insecticide exposure on NAFLD remains unknown. Therefore, this project investigated the roles of insecticide exposure in the development of NAFLD using HepG2 hepatocytes. First, 12 insecticides were tested for their effects on triglycerides (TG) accumulation and interactions with palmitic acid (PA), which induces steatosis. Among tested insecticides, permethrin and ivermectin significantly altered TG accumulation and interacted with PA. Further mechanistic studies showed that permethrin promoted lipogenesis …

Screening Of Commercially Available Chlorine Based Sanitizers And Their Efficacy In Reducing Microbial Load Levels Of E. Coli O157:H7 At High And Low Organic Load Environments, Paola Martinez-Ramos

Masters Theses

The presence of postharvest sanitizers has shown to be an effective approach to reducing microbial cross contamination in agricultural washing operations. However, choosing an appropriate sanitizer can be challenging due to produce commodity, processing conditions and interference with organic load. Current research shows a wide variety of methods to mimic the organic load of vegetable processing conditions, with paddle mixing and blender as the most commonly used. Controlling and understanding the physiochemical properties of wash water is key in maintaining sanitizer efficacy. The effects of simulated wash water preparation method on the physiochemical properties were tested at 0 and 50 …

Optimization Of Peracetic Acid As An Antimicrobial Agent In Postharvest Processing Wash Water, Tiah Ghostlaw

Masters Theses

The Food Safety Modernization Act (FSMA) has a regulation stating that there can be no detectable generic Escherichia coli in agricultural water. The objective of this study was to optimize the use of peracetic acid (PAA) as a mitigating strategy in postharvest processing. This project began by investigating the impact of storage temperatures on stability of a commercially available PAA sanitizer. Regression analysis showed a quadratic relationship in the concentration of PAA over 12 weeks when storing the product at 4, 20 and 37°C. Stability of the product was also investigated in the presence of organic load over time at …

Interaction Of Titanium Dioxide Nanoparticles (Nps) With Food Components And Mechanistic Studies Of Adverse Effects Induced By Titanium Dioxide Nps, Xiaoqiong Cao

Doctoral Dissertations

Many food products contain engineered inorganic nanoparticles (NPs), such as titanium dioxide (TiO₂) NPs as a part of food additive, due to both unintentional and intentional additions. There has been increasing concern about the health risks associated with foodborne inorganic NPs. However, the detailed understanding of the biological fate and potential adverse effects of foodborne TiO₂ NPs is not available despite a limited number of published toxicity studies on TiO₂ NPs. The purpose of this thesis was to characterize the interactions of TiO₂ NPs and food components including dietary flavonoids and dietary proteins, …

Biological Effects And Action Mechanisms Of Dietary Compounds, Elvira Sukamtoh

Masters Theses

The food that we consume contain many dietary compounds which are biologically active. In this thesis we will discuss the biological effects of dietary compounds and the mechanisms behind their activities.

First, we studied on the anti-metastatic effects of curcumin, a dietary compound derived from turmeric, through lymphangiogenesis inhibition. Curcumin inhibited vascular endothelial growth factor-C (VEGF-C)-induced lymphangiogenesis in vivo and in vitro. Curcumin inhibited lymphangiogenesis, in part through suppression of proliferation, cell cycle progression and migration of lymphatic endothelial cells. Curcumin inhibited expressions of VEGF receptors (VEGFR2 and VEGFR3), as well as down-stream signaling such as phosphorylation of ERK …

Extractable And Non-Extractable Polyphenols From Mango, Yuchao Ma

Masters Theses

Polyphenol from fruits and vegetables have been proved that can lower the risk of many chronic disease. However, most studies are only focus on the extractable polyphenols right now. Non-extractable polyphenols may also have many important biological effects. The objective of this study was to find the difference between the extractable polyphenol and non-extractable by alkaline hydrolysis, acid hydrolysis and enzyme hydrolysis, compare the total phenolic content, flavonoid content and tannin content, and study their anti-inflammation effect, anti-cancer effect and antioxidant effect. The results showed that NEP alkaline hydrolysis was the best way to extract mango polyphenol. It had the …