Life Sciences Commons^™

Characterization Of Starch By Vibrational Spectroscopy, Brandon H. Holder

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

To develop a dispersive Raman spectroscopic method for measuring amylose-amylopectin ratios of corn starch mixtures, 67 mixtures were prepared by randomly mixing waxy and normal corn starches. Amylose contents were measured using a dual wavelength iodine binding colorimetric method. Raman data were collected from 250 to 3200 cm^-1 using optimized instrument parameters. Partial least-squares (PLS) and principal components regression (PCR) were used to prepare multivariate calibration models; however, PLS commonly outperformed PCR. Truncating the spectra to 250 to 2000 cm^-1 improved the results (r² of validation = 0.831, SEP = 2.90%). Removal of a cold water swelling …

Differential Surface Deposition Of Complement Proteins On Logarithmic And Stationary Phase Leishmania Chagasi Promastigotes, Amanda Ramer-Tait, Soi Meng Lei, Bryan H. Bellaire, Jeffrey K. Beetham

Department of Food Science and Technology: Faculty Publications

Previous works demonstrated that various species of Leishmania promastigotes exhibit differential sensitivity to complement-mediated lysis (CML) during development. Upon exposure to normal human serum (NHS), cultures of Leishmania chagasi promastigotes recently isolated from infected hamsters (fewer than 5 in vitro passages) are CML-sensitive when in the logarithmic growth phase but become CML-resistant upon transition to the stationary culture phase. Visualization by light and electron microscopy revealed dramatic morphological differences between promastigotes from the 2 culture phases following exposure to NHS. Flow cytometric analysis demonstrated that surface deposition of the complement components C3, C5, and C9 correlated inversely with promastigote CML-resistance. …

New Technologies For Whole Wheat Processing: Addressing Milling And Storage Issues, Andres F. Doblado-Maldonado

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

Whole wheat flour production and demand has increased dramatically during the last decade due to evidence supporting the benefits of whole grains in the diet. Hence, the food industry has provided a wide variety of new whole grain products. There are unique challenges that accompany whole wheat flour production, especially related to milling and storage. The present thesis provides new strategies on the adaptation of new technologies to overcome whole wheat processing issues. These issues are first discussed in a literature review and then followed by three research studies. In the first study, retail whole wheat flours were evaluated for …

Evidence Of Transmission Of Escherichia Coli O157:H7 To The Tissues Or Phyllo-Plane Of Wheat, From Contaminated Soil, Seeds Or Water, Bismarck Antonio Martinez

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

Escherichia coli O157:H7 is a human pathogen that can cause a wide spectrum of disease symptoms, such as bloody diarrhea, hemorrhagic colitis, and hemolytic uremic syndrome (HUS). Escherichia coli O157:H7 illness are mainly associated with undercooked beef; however, in recent years outbreaks have been linked to fresh produce such as spinach, lettuce, and sprouts. In 2009, flour was implicated as a contamination source in the consumption of raw cookie dough resulting in 77 illness-cases. The objective of this research was to determine the possible route of transmission of E. coli O157:H7 into the phyllo-plane of wheat using contaminated seed, soil …

Measuring Parvalbumin Levels In Fish Muscle Tissue: Relevance Of Muscle Locations And Storage Conditions, Poi-Wah Lee, Julie A. Nordlee, Stef J. Koppelman, Joseph L. Baumert, Steve L. Taylor

Department of Food Science and Technology: Faculty Publications

Fish is an allergenic food capable of provoking severe anaphylactic reactions. Parvalbumin is the major allergen identified in fish and frog muscles. Antibodies against fish and frog parvalbumin have been used to quantify parvalbumin levels from fish. However, these antibodies react variably with parvalbumin from different fish species. Several factors might be responsible for this variation including instability of parvalbumin in fish muscle as a result of frozen storage and differential parvalbumin expression in muscles from various locations within the whole fish. We aimed to investigate whether these factors contribute to the previously observed variable immunoreactivity of the anti-parvalbumin antibodies. …

Genetic Characterization Of North American Populations Of The Wheat Curl Mite And Dry Bulb Mite, Gary L. Hein, Roy French, Benjawan Siriwetwiwat, James W. Amrine

Department of Entomology: Faculty Publications

The wheat curl mite, Aceria tosichella Keifer, transmits at least three harmful viruses, wheat streak mosaic virus (WSMV), high plains virus (HPV), and Triticum mosaic virus (TriMV) to wheat (Triticum aestivum L.) throughout the Great Plains. This virus complex is considered to be the most serious disease of winter wheat in the western Great Plains. One component of managing this disease has been developing mite resistance in wheat; however, identification of mite biotypes has complicated deployment and stability of resistance. This biotypic variability in mites and differential virus transmission by different mite populations underscores the need to better understand …

Parvalbumin In Fish Skin–Derived Gelatin: Is There A Risk For Fish Allergic Consumers?, S. J. Koppelman, J. A. Nordlee, P.-W. Lee, R. P. Happe, M. Hessing, R. Norland, T. Manning, R. Deschene, G. A. H. De Jong, S. L. Taylor

Department of Food Science and Technology: Faculty Publications

The major allergen parvalbumin was purified from cod muscle tissues, and polyclonal antibodies were raised toward it. The antibodies were tested for specificity, and an enzyme-linked immunosorbent assay (ELISA) was developed using these antibodies. The ELISA was applied to measure parvalbumin in cod skin, the starting material for fish gelatin made from deep sea, wild fish. The ELISA was sufficiently sensitive (LLOQ = 0.8 ng ml^–1 in extracts, corresponding to 0.02 μg of parvalbumin per g of tissue) and did not cross-react with common food constituents. Fish gelatin, wine, and beer, matrices for the potential use of this ELISA, …

Analysis Of Microbial Diversity By Amplicon Pyrosequencing, Ryan Legge

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

Microorganisms numerically dominate terrestrial biodiversity, and play important biochemical and geochemical roles in the environments they inhabit. To understand structure and function of complex ecosystems, it is essential to identify primary drivers of microbial diversity and community structure. Historically, the study of microbial ecology was reductive, limited to microbes able to be cultured and enumerated. Microbes meeting this criterion were thought to comprise the dominating members of the environments they were isolated from, however, estimates suggesting up to 99% of the endogenous species are uncultivable with existing methodologies; a concept that reflects experimental failure, rather than a verifiable conclusion. Therefore …

Gene Expression In Intestinal Mucosal Biopsy Specimens Obtained From Dogs With Chronic Enteropathy, Vicki L. Wilke, Dan Nettleton, Meghan J. Wymore, Jack M. Gallup, Cumhur Yusuf Demirkale, Mark R. Ackermann, Chris K. Tuggle, Amanda E. Ramer-Tait, Michael J. Wannemeuhler, Albert E. Jergens

Department of Food Science and Technology: Faculty Publications

Objective—To characterize mucosal gene expression in dogs with chronic enteropathy (CE). Animals—18 dogs with CE and 6 healthy control dogs.

Procedures—Small intestinal mucosal biopsy specimens were endoscopically obtained from dogs. Disease severity in dogs with CE was determined via inflammatory bowel index scores and histologic grading of biopsy specimens. Total RNA was extracted from biopsy specimens and microchip array analysis (approx 43,000 probe sets) and quantitative reverse transcriptase PCR assays were performed.

Results—1,875 genes were differentially expressed between dogs with CE and healthy control dogs; 1,582 (85%) genes were downregulated in dogs with CE, including neurotensin, fatty …

Seasonal Population Dynamics Of The Potato Psyllid (Hemiptera: Triozidae) And Its Associated Pathogen “Candidatus Liberibacter Solanacearum” In Potatoes In The Southern Great Plains Of North America, John A. Goolsby, John J. Adamczyk Jr., J. M. Crosslin, Noel N. Troxclair, J. R. Ancisco, Gerhard G. Bester, J. D. Bradshaw, Edsel D. Bynum Jr., L. A. Carpio, Don C. Henne, Ankush Joshi, Joseph E. Munyaneza, Pat Porter, Phillip E. Sloderbeck, J. R. Supak, C. M. Rush, F. J. Willett, B. J. Zechmann, B. A. Zens

Department of Entomology: Faculty Publications

The potato psyllid, Bactericera cockerelli (Sulc) (Hemiptera: Triozidae), and its associated pathogen “Candidatus Liberibacter solanacearum” (Ca. L. solanacearum), the putative causal agent of zebra chip (ZC) disease in potatoes (Solanum tuberosum L.), were sampled in commercial potato fields and untreated control plots for 3 yr in multiple locations in Texas, Kansas, Nebraska, and Colorado. Populations of the potato psyllid varied across years and across potato growing regions. However, the percentage of potato psyllids infected with Ca. L. solanacearum although variable across years, was consistently highest in the Lower Rio Grande Valley of Texas (LRGV), the reported overwintering …

The Trade And Welfare Impacts Of Australian Quarantine Policies: The Case Of Pigmeat, John C. Beghin, Mark Melatos

Department of Agricultural Economics: Faculty Publications

We analyze the trade and welfare impact of quarantine measures imposed by Australia on imports of pigmeat. In particular, we account for changes to Australia’s pigmeat quarantine policy over time, including those changes related to the recent resolution of a WTO dispute between Australia and the European Union. Using a random utility model and applying it to corner solutions in import decisions, tariff equivalents (by major trading partner) are estimated for the different pigmeat quarantine regimes implemented by Australia during the period 1988-2009. The welfare impact on consumers, producers, and foreign exporters is computed using a partial equilibrium model calibrated …

Host-Microbe-Diet Interplay: Dietary Modulation Of The Gut Microbiota In Relation To Health, Inés Martínez

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

Vertebrates are associated with trillions of bacteria, with the densest populations residing in the large intestine. The symbiosis between vertebrates and their gut microbiota has resulted in important implications of the gut microbiome on host health. Diet is an important factor that shapes gut microbiota composition, and because of the interplay between host-microbiome-diet, dietary strategies that modulate gut microbiome structure are deemed a relevant tool to improve host health. However, gaps in knowledge exist with respect to these interactions, and it is essential to obtain a mechanistic understanding of how these relations take place to develop successful therapeutic strategies that …

Evaluation Of A Social Marketing Campaign: 4 Day Throw Away, Katie J. James

Department of Nutrition and Health Sciences: Dissertations, Theses, and Student Research

Children are at a heightened risk for foodborne illness. Handling leftover food safely was identified as a concern from focus groups with the main food preparer in families with young children in two Midwestern states. To design, implement, and evaluate a theory-based food safety education intervention to raise awareness of the USDA guideline for handling leftover food. The food safety social marketing campaign “4 Day Throw Away” launched in towns throughout Nebraska and Iowa. The campaign included both traditional and social media methods to relay the message of discarding leftovers after four days. A total of 600 guardians of young …

Microbial Co-Occurrence Relationships In The Human Microbiome, Karoline Faust, J. Fah Sathirapongsasuti, Jacques Izard, Dirk Gevers, Jeroen Raes, Curtis Huttenhower

Department of Food Science and Technology: Faculty Publications

The healthy microbiota show remarkable variability within and among individuals. In addition to external exposures, ecological relationships (both oppositional and symbiotic) between microbial inhabitants are important contributors to this variation. It is thus of interest to assess what relationships might exist among microbes and determine their underlying reasons. The initial Human Microbiome Project (HMP) cohort, comprising 239 individuals and 18 different microbial habitats, provides an unprecedented resource to detect, catalog, and analyze such relationships. Here, we applied an ensemble method based on multiple similarity measures in combination with generalized boosted linear models (GBLMs) to taxonomic marker (16S rRNA gene) profiles …

Composition Of The Adult Digestive Tract Bacterial Microbiome Based On Seven Mouth Surfaces, Tonsils, Throat And Stool Samples, Nicola Segata, Susan Kinder Haake, Peter Mannon, Katherine P. Lemon, Levi Waldron, Dirk Gevers, Curtis Huttenhower, Jacques Izard

Department of Food Science and Technology: Faculty Publications

Background: To understand the relationship between our bacterial microbiome and health, it is essential to define the microbiome in the absence of disease. The digestive tract includes diverse habitats and hosts the human body’s greatest bacterial density. We describe the bacterial community composition of ten digestive tract sites from more than 200 normal adults enrolled in the Human Microbiome Project, and metagenomically determined metabolic potentials of four representative sites.

Results: The microbiota of these diverse habitats formed four groups based on similar community compositions: buccal mucosa, keratinized gingiva, hard palate; saliva, tongue, tonsils, throat; sub- and supra-gingival plaques; and stool. …

A Framework For Human Microbiome Research, Barbara A. Methe, Jacques Izard

Department of Food Science and Technology: Faculty Publications

A variety of microbial communities and their genes (the microbiome) exist throughout the human body, with fundamental roles in human health and disease. The National Institutes of Health (NIH)-funded Human Microbiome Project Consortium has established a population-scale framework to develop metagenomic protocols, resulting in a broad range of quality-controlled resources and data including standardized methods for creating, processing and interpreting distinct types of high-throughput metagenomic data available to the scientific community. Here we present resources from a population of 242 healthy adults sampled at 15 or 18 body sites up to three times, which have generated 5,177 microbial taxonomic profiles …

Structure, Function And Diversity Of The Healthy Human Microbiome, Curtis Huttenhower, Jacques Izard

Department of Food Science and Technology: Faculty Publications

Studies of the human microbiome have revealed that even healthy individuals differ remarkably in the microbes that occupy habitats such as the gut, skin and vagina. Much of this diversity remains unexplained, although diet, environment, host genetics and early microbial exposure have all been implicated. Accordingly, to characterize the ecology of human-associated microbial communities, the Human Microbiome Project has analysed the largest cohort and set of distinct, clinically relevant body habitats so far. We found the diversity and abundance of each habitat’s signature microbes to vary widely even among healthy subjects, with strong niche specialization both within and among individuals. …

Metabolic Reconstruction For Metagenomic Data And Its Application To The Human Microbiome, Sahar Abubucker, Nicola Segata, Johannes Goll, Alyxandria M. Schubert, Jacques Izard, Brandi L. Cantarel, Beltran Rodriguez-Mueller, Jeremy Zucker, Mathangi Thiagarajan, Bernard Henrissat, Owen White, Scott T. Scott, Barbara Methe´, Patrick D. Schloss, Dirk Gevers, Makedonka Mitreva, Curtis Huttenhower

Department of Food Science and Technology: Faculty Publications

Microbial communities carry out the majority of the biochemical activity on the planet, and they play integral roles in processes including metabolism and immune homeostasis in the human microbiome. Shotgun sequencing of such communities’ metagenomes provides information complementary to organismal abundances from taxonomic markers, but the resulting data typically comprise short reads from hundreds of different organisms and are at best challenging to assemble comparably to single-organism genomes. Here, we describe an alternative approach to infer the functional and metabolic potential of a microbial community metagenome. We determined the gene families and pathways present or absent within a community, as …

Analyzing Cellular Internalization Of Nanoparticles And Bacteria By Multi-Spectral Imaging Flow Cytometry, Yashdeep Phanse, Amanda E. Ramer-Tait, Sherree L. Friend, Brenda Carrillo-Conde, Paul Lueth, Carrie J. Oster, Gregory J. Phillips, Balaji Narasimhan, Michael J. Wannemuehler, Bryan H. Bellaire

Department of Food Science and Technology: Faculty Publications

Nanoparticulate systems have emerged as valuable tools in vaccine delivery through their ability to efficiently deliver cargo, including proteins, to antigen presenting cells^1-5. Internalization of nanoparticles (NP) by antigen presenting cells is a critical step in generating an effective immune response to the encapsulated antigen. To determine how changes in nanoparticle formulation impact function, we sought to develop a high throughput, quantitative experimental protocol that was compatible with detecting internalized nanoparticles as well as bacteria. To date, two independent techniques, microscopy and flow cytometry, have been the methods used to study the phagocytosis of nanoparticles. The high throughput …

Harvesting Murine Alveolar Macrophages And Evaluating Cellular Activation Induced By Polyanhydride Nanoparticles, Ana V. Chavez-Santoscoy, Lucas M. Huntimer, Amanda Ramer-Tait, Michael Wannemueler, Balaji Narasimhan

Department of Food Science and Technology: Faculty Publications

Biodegradable nanoparticles have emerged as a versatile platform for the design and implementation of new intranasal vaccines against respiratory infectious diseases. Specifically, polyanhydride nanoparticles composed of the aliphatic sebacic acid (SA), the aromatic 1,6-bis(p -carboxyphenoxy)hexane (CPH), or the amphiphilic 1,8-bis(p-carboxyphenoxy)-3,6-dioxaoctane (CPTEG) display unique bulk and surface erosion kinetics^1,2 and can be exploited to slowly release functional biomolecules (e.g., protein antigens, immunoglobulins, etc.) in vivo^3,4,5. These nanoparticles also possess intrinsic adjuvant activity, making them an excellent choice for a vaccine delivery platform^6,7,8.

In order to elucidate the mechanisms governing the activation of innate …

Dsc Enthalpic Transitions During Starch Gelatinization In Excess Water, Dilute Sodium Chloride, And Dilute Sucrose Solutions, Wajira S. Ratnayake, Chika Otani, David S. Jackson

Department of Food Science and Technology: Faculty Publications

Background: Starch phase transition characteristics were studied by pre-treating starch samples in excess water, dilute sodium chloride and dilute sucrose solutions and subjecting them to differential scanning calorimetry (DSC). Unmodified maize, wheat and potato starches were held at specific temperatures between 30 and 90 °C for 30 min and promptly cooled to 25 °C. Treated samples were then analyzed in situ by DSC. Results: It was found that the progression of the phase transition behavior differed among the three starches and was dependent on the solvent. It was also revealed that phase transition-related enthalpic changes started to occur at low …

Influence Of Dietary Fibers And Whole Grains On Fecal Microbiota During In Vitro Fermentation, Junyi Yang

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

There has been a dramatic increase in obesity, which presents a risk of many chronic health problems. Recent studies have shown that obese individuals harbor an abnormal gut microbiota (dysbiosis), which has sparked interest in the gut microbiota as a target for weight management. Dietary fiber and whole grains that can be metabolized by gut microbiota have been shown to promote the growth of beneficial bacteria in the gut. Increased consumption of dietary fiber and whole grains may improve host / gut microbiota interactions in obesity and other metabolic diseases by normalizing gut dysbiosis. The present thesis describes two research …

Ars Assists In Fight Against Kudzu Bug, Jan Suszkiw, Walker Jones

Agricultural Research Magazine

Sure, this distant relative of the brown marmorated stink bug will feed voraciously on the stems of kudzu, the “Vine That Ate the South.” But Megacopta cribraria also has a taste for soybean and other legumes. In Georgia, where this native of Asia was first discovered in the United States in October 2009, there’s worry that the pest will set its sights on peanut, endangering a $2 billion crop that supplies nearly 50 percent of America’s peanuts (Georgia Peanut Commission, 2009).

Like the brown marmorated stink bug, Megacopta—also known as the “bean plataspid”—seeks shelter inside homes, buildings, and vehicles …

Flow Rate, And More, Ann Perry

Agricultural Research Magazine

At the Agricultural Research Service’s Northwest Irrigation and Soils Research Laboratory in Kimberly, Idaho, agricultural engineer Brad King and research leader Dave Bjorneberg compared how irrigation from four commercial center-pivot sprinklers affected potential runoff and erosion on four south-central Idaho soils.

Though their results were inconsistent, they did observe that at the end of six irrigations, a 50-percent reduction in sprinkler flow rate reduced runoff and soil erosion 60-80 percent. They concluded that reducing sprinkler flow rate early in the growing season—before the development of a crop canopy—could help reduce irrigation runoff and soil erosion linked to center-pivot sprinkler irrigation. …

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150 Years of Making History

USDA's 150th Anniversary- May 15, 2012

Forum: Alternative Strategies For Keeping Animals Healthy, Cyril G. Gay

Agricultural Research Magazine

The general public needs to know more about the importance of preventing and controlling livestock diseases and the financial impact they would have on our lives and food supply if left unchecked. Part of our mission at the USDA Agricultural Research Service is to conduct research to protect the safety of our nation’s agriculture and food supply through improved disease detection, prevention, and control.

Antibiotics are recognized as one of the most important biomedical discoveries for treating infectious diseases of animals and humans. The use of antibiotics has had a major impact on increases in food-animal production and has resulted …

New Insights Into Irrigation Management, Ann Perry

Agricultural Research Magazine

Pacific Northwest potato and sugar beet farmers who irrigate their crops with sprinklers need to know a lot more than when to turn on the faucet. The region’s powdery silt loam soils don’t contain much stabilizing organic matter, and existing soil aggregates that facilitate water infiltration can be broken up during irrigation. Afterwards, the loose particles of sand, silt, and clay that remain can dry to form a solid crust that greatly limits infiltration into the soil.

This means that growers not only need to calculate how much water should be supplied during irrigation, but they also need to ensure …

Genetics And Bermudagrass: It's Not Easy Being Uniformly Green, Dennis O’Brien, Karen Harris

Agricultural Research Magazine

Golfers and golf course superintendents expect a lot from their putting greens. They want fine, lush, carpetlike surfaces that a ball will roll smoothly across. They also want a grass that tolerates frequent low mowing, has uniform color and texture, tolerates pests and cold temperatures, and offers a dense canopy that shades out weeds to minimize the need for herbicides.

Southern putting greens are made up of single cultivars of bermudagrass, but golf course superintendents have complained for years about the appearance of nonuniform plants, or “off-types,” that can throw off the green’s appearance and “playability.” The bermudagrass cultivar Tifgreen, …

New Tool Opens A Bigger Window To Insect-Plant Warfare, Dennis O’Brien, Elaine Backus

Agricultural Research Magazine

When an aphid, leafhopper, or psyllid lands on a plant to feed, it begins a process of chamical welfare. As piercing-sucking insects, they use needlelike stylets to insert saliva into plant tissues and open a pathway to ingest fluids critical to the plant’s survival. When punctured, the plant senses the attack and secretes proteins and other chemical defenses to prevent fluids from being pulled out, thus creating a stress on the plant. This warfare costs growers billions of dollars each year in lost ornamentals, vegetables, citrus, and other important agricultural crops.

Because much of the action takes place in the …