Master of Science, The Ohio State University, 2020, Food Science and Technology

Pomegranate juice is a complex mixture of structurally diverse compounds appearing in various concentrations and the composition of final product depends on several factors such as variety, geographical origin and adulteration. It is therefore an excellent system for assessing the potential of an analytical method for rapid, targeted and untargeted analysis. Here we tested the ability of 1D and 2D NMR spectroscopy techniques for the determination of pomegranate juice constituents and for evaluating the impact of various factors on its composition. The NMR spectra assignment was performed using the novel NOAH sequences and spiking with model compounds. Several metabolites including sugars, organic acids and amino acids were identified and quantified. Several internal standards were tested with potassium hydrogen phthalate and dimethylmalonic acid found to be the most appropriate, while MnCl2 was successfully tested as a relaxation agent for the reduction of the experimental time. Among the pulse sequences that were tested for their quantitative potential, the simple pulse-acquire, the z-stored inverse gated decoupling, the Carr-Purcell-Meiboom-Gill (CPMG) and the QEC-HSQC experiments gave the best results. 1D and 2D NMR-based untargeted analysis was able to differentiate between various pomegranate cultivars and geographical origins, as well as detect the adulteration with apple juice. This study provides the proof of concept for 1D and 2D NMR methods in the targeted/untargeted analysis of pomegranate juice and can be extended to other complex matrixes.

Committee: Emmanuel Hatzakis (Advisor); Luis Rodriguez-Saona (Committee Member); Christopher Simons (Committee Member) Subjects: Food Science

Doctor of Philosophy, The Ohio State University, 2017, Food, Agricultural and Biological Engineering

Natural rubber (NR) is a raw material vital to the modern economy produced from a single plant species (Hevea brasiliensis) and the supply of which is insecure. Taraxacum kok-saghyz (TK) is an ideal rubber-producing crop because it synthesizes high quality rubber with similar composition, molecular characteristics, and mechanical properties to hevea NR. Extensive research on the development of TK as a commercially feasible crop is underway. Nonetheless, little research has been done on processing for the recovery of rubber, and byproducts. In this work, a comprehensive compositional analysis of field harvested TK roots was conducted to identify components that may have commercial value. Based on this analysis, new aqueous processes for the extraction of NR from TK roots that feature the use of alkaline pretreatment and enzymatic hydrolysis were investigated. Likewise, these processes were compared to wet milling treatments in order to identify those that result in NR of high purity, yield, and quality. Furthermore, alkaline pretreatment of TK roots at temperatures between 25 and 160°C, and NaOH loadings from 33 to 132 mg NaOH/g TK roots, was further studied to identify its impact on rubber yield, purity, and quality. Additionally, reliable methods to quantify primary TK root components were developed to allow the analysis of the large numbers of samples produced in the development of TK roots. The compositional analysis mass closure was greater than 95%. The roots contained 5.4% rubber and 1.7% resins. 60% of the root was hot water extractable. Inulin (18%) and proteins (10%) were the most abundant water-soluble fractions. Insoluble components included cellulose 9%, hemicellulose 7%, lignin 5%, protein 5% and pectin 3%. Based on the compositional analysis and current TK field plant density data, potential yields of various biobased products were calculated. Results indicated that TK is a potential source of NR and other products of importance such as inulin and prot (open full item for complete abstract)

Committee: Frederick Carl Michel (Advisor); Katrina Cornish (Advisor); Ajay Shah (Committee Member); Thaddeus Ezeji (Committee Member) Subjects: Agricultural Chemicals; Agricultural Engineering; Chemical Engineering; Engineering; Materials Science; Polymers

Master of Science in Chemical Engineering, University of Toledo, 2011, Chemical Engineering

The concern over the increasing depletion of our nation's fossil fuels, high oil prices and greenhouse gas emissions, has motivated research for alternative sources of energy. One alternative energy source, biofuels, provides liquid transportation fuels from biomass derived from plant or animal sources. First generation biofuels are produced from food crops abundant in sugars or lipids such as corn and soy. Second generation biofuels are produced from woody, inedible crops such as poplar and switchgrass. The third generation of biofuels is derived from algae and is of growing interest due to its high yield of energy per unit area, use of carbon dioxide for growth, and minimal contribution as a food product. The main carbon rich components of algal biomass include lipid, carbohydrates and protein. Products such as biodiesel and jet fuel can be derived from lipids. Carbohydrates, in the form of fermentable sugars, can be used to produce bioalcohols. Protein can be used as a dietary supplement or as feed for livestock. This work addresses algal characterization and processing techniques that are helpful in utilizing algae as a feedstock for bioproduct processing. Methods for lipid analysis are compared to select a technique for small sample sizes and ease of handling. The hydrolysis of soybean oil to convert triglycerides (lipids) to free fatty acids is evaluated. A kinetic model is developed to predict reaction behavior and serve as a platform for algal hydrolysis. Characterization techniques to determine the content of algal biopolymers; lipids, carbohydrates and protein are discussed and applied to multiple algal species. Lastly, protein extraction from alga is investigated to prepare species for successful algal hydrolysis.

Committee: Constance Schall (Advisor); Dong-Shik Kim (Committee Member); Cyndee Gruden (Committee Member) Subjects: Alternative Energy; Chemical Engineering

Master of Science, The Ohio State University, 2011, Environment and Natural Resources

Despite a long history of research and accumulated knowledge of factors affecting population growth rates, conservation efforts aimed at reversing population declines of northern bobwhites (Colinus virginianus) have been largely ineffective. Bobwhite population decline and range contraction across the Midwest was driven primarily by changes in land-use practices related to large-scale intensive agriculture, urbanization, and forest succession. Although changes in agricultural landscapes have contributed substantially to the decline, such landscapes remain the only area where active management may improve population growth rates. To understand the ecology of bobwhites in agricultural landscapes in Ohio, I used radio-telemetry to investigate survival and habitat use during the non-breeding season (October–March) on 4 private land study sites in southwestern Ohio during 2009-2011. Known-fates survival estimates were low in both years (S2009-2010=0.05, 95% CI=0.03, 0.11, S2010-2011=0.12, 95% CI=0.07, 0.20) and lowest weekly survival coincided with periods of prolonged snow cover. Compositional analysis revealed that coveys used habitat non-randomly at 3 scales; positioning of home ranges within study areas (Λ = 0.320, P < 0.001), positioning of core areas within home range (Λ = 0.599, P = 0.002), and point locations within home ranges (Λ = 0.058, P = 0.002). Early successional woody vegetation (e.g. fencerows and ditches) was the most preferred habitat type at all scales. Differences in selection among study sites revealed that home ranges were preferentially established in areas with grassland cover on 2 agricultural study sites, but not at the site with the greatest amount of grassland cover. Bobwhites mostly used habitat edges such that interior portions of grass and crop fields were used less as they increased in area. Thus small fields with high edge to interior ratios are most advantageous. I tested the influence of habitat use on individual survival by comparing (open full item for complete abstract)

Committee: Robert Gates PhD (Advisor); Amanda Rodewald PhD (Committee Member); Stanley Gehrt PhD (Committee Member) Subjects: Ecology; Natural Resource Management; Wildlife Conservation; Wildlife Management

Master of Science, The Ohio State University, 2013, Environment and Natural Resources

Northern bobwhites are a popular upland game bird species with economic and social importance. Despite nearly a century of research, population declines continue at state and national scales. Precipitous population declines and range-contractions in the Midwest have been caused by land-use changes and suppression of natural disturbance regimes. Reproduction that meets or exceeds annual mortality is essential to sustain viable populations and poor reproductive success is also implicated in declines of grassland bird populations. This study fills an information gap in knowledge of spring dispersal, breeding ecology and behavior, and breeding vital rates of Midwestern bobwhites near the northern limit of their range. It is unclear if recovery of Midwestern bobwhite populations is limited by spring dispersal capabilities and/or breeding vital rates. Radio-telemetry was used to investigate breeding vital rates during 2010 and 2011 on 4 private-lands study sites in southwest Ohio. Bobwhites were outfitted with radio-transmitters with an 8-hr mortality sensor and tracked daily with homing to within ≤20m. Spring dispersal and breeding season vital rates were evaluated and compared to other bobwhite populations to identify potential population-limiting factors associated with spring dispersal and reproduction. Vital rates that met or exceeded range-wide means included spring dispersal distance (1.54 km), nesting effort (re-nest = 26%, double clutch = 65%), male incubation (43% of nests), clutch size (14.4 eggs), egg success (96.9%), and nesting phenology. The mean hatch date for first nest attempts was 1 July, 21 July for male incubated nests, 28 July for renests, 31 July for backdated fall-juveniles, and 24 Aug for double clutches. Breeding season (Apr-Sep) survival (28%) and nest success (27.9%) were lower in southwestern Ohio compared to range-wide averages. Relatively low nest success and breeding season survival indicates that reproduction may limit population growth i (open full item for complete abstract)

Committee: Robert Gates PhD (Advisor); Paul Rodewald PhD (Committee Member); Elizabeth Marschall PhD (Committee Member) Subjects: Animals; Ecology; Natural Resource Management; Wildlife Conservation; Wildlife Management