UARK (University of Arkansas )
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Effects of Black Raspberry, Blueberry, and Blackberry Volatile Extracts on Intestinal Barrier Dysfunction and Inflammation in a Caco-2/RAW264.7 Cells Co-culture Model
Get PDFBerry volatiles are responsible for the aroma of berries. However, their impacts on intestinal inflammation are unclear. Thus, this study investigated the effects of black raspberry, blueberry, and blackberry volatile extracts (BVEs) on intestinal barrier dysfunction and inflammation using a Caco-2/RAW264.7 cells co-culture model. BVE treatments significantly enhanced integrity and decreased permeability in LPS-damaged epithelial monolayers with increased tight junctions. Blueberry and blackberry volatile extract treatments significantly inhibited the LPS-induced overproduction of NO, IL-6, and TNF-α (p \u3c 0.05). BVEs also suppressed the LPS-induced phosphorylation of p65, IKKα, and IκBα. These findings revealed that volatile extracts from black raspberries, blueberries, and blackberries improve intestinal barrier dysfunction by enhancing intestinal epithelial monolayer integrity and exhibit intestinal anti-inflammatory effects by suppressing pro-inflammatory mediator and cytokines through modulating NF-κB signaling pathway. It suggests that the three berry volatile extracts have the potential as functional food components with gastrointestinal protective effects with anti-inflammatory properties
Bootstrapping for Estimating the Conservative Kill Ratio of the Surrogate to the Pathogen for Use in Thermal Process Validation at the Industrial Scale
Get PDFA surrogate is commonly used for process validations. The industry often uses the target log cycle reduction for the test (LCRTest) microorganism (surrogate) to be equal to the desired log cycle reduction for the target (LCRTarget) microorganism (pathogen). When the surrogate is too conservative with far greater resistance than the pathogen, the food may be overprocessed with quality and cost consequences. In aseptic processing, the Institute for Thermal Processing Specialists recommends using relative resistance (DTarget)/(DTest) to calculate LCRTest (product of LCRTarget and relative resistance). This method uses the mean values of DTarget and DTest and does not consider the estimating variability. We defined kill ratio (KR) as the inverse of relative resistance. The industry uses an extremely conservative KR of 1 in the validation of food processes for low-moisture foods, which ensures an adequate reduction of LCRTest, but can result in quality degradation. This study suggests an approach based on bootstrap sampling to determine conservative KR, leading to practical recommendations considering experimental and biological variability in food matrices. Previously collected thermal inactivation kinetics data of Salmonella spp. (target organism) and Enterococcus faecium (test organism) in Non-Fat Dried Milk (NFDM) and Whole Milk Powder (WMP) at 85, 90, and 95°C were used to calculate the mean KR. Bootstrapping was performed on mean inactivation rates to get a distribution of 1000 bootstrap KR values for each of the treatments. Based on minimum temperatures used in the industrial process and acceptable level of risk (e.g., 1, 5, or 10% of samples that would not achieve LCRTest), a conservative KR value can be estimated. Consistently, KR increased with temperature and KR for WMP was higher than NFDM. Food industries may use this framework based on the minimum processing temperature and acceptable level of risk for process validations to minimize quality degradation
Knowledge Gaps About Micronutrient Deficiencies in Tanzania and the Effect of Information Interventions
Get PDFReducing micronutrient malnutrition (“hidden hunger”) in low-income countries is a global challenge, particularly among women, children, and high-poverty households. Countries like Tanzania have developed diverse strategies to combat malnutrition, including the biofortification of staple foods. However, broad awareness and knowledge of micronutrient deficiencies and beneficial foods are needed for these strategies to be effective. The objectives of this study were to (i) examine Tanzanian consumers\u27 initial awareness and knowledge of deficiencies for four micronutrients and associated biofortified foods, and (ii) to examine the effectiveness of targeted communication approaches (i.e., information and branding) to improve knowledge. Data were collected from 1029 respondents in Tanzania using an online survey. Respondents were randomly assigned to treatments across two experiments in the survey. One experiment examined the effect of information about susceptibility and severity of micronutrient deficiencies and foods that reduce the risk of deficiency, and the other experiment examined the impact of ‘branding’ biofortified foods. The combination of providing information and branded biofortified crops most effectively reduced knowledge gaps about negative health outcomes and risk-reducing foods. Results suggest a need for evidence-based interventions that provide broad nutrition education and financial assistance for purchasing food
Use of a Capsule Suspension Formulation of \u3ci\u3eS\u3c/i\u3e-metolachlor in Fenclorim-Treated Rice
Get PDFAs herbicide resistance continues to render commonly used rice herbicides ineffective, alternative sites of action are paramount to maintaining yield and producer profitability. Combining a slow-release formulation and a fenclorim seed treatment might allow the safe use of S-metolachlor in rice. Experiments were initiated in 2022 and 2023 near Colt, AR, on a silt loam soil to evaluate crop safety using a capsule suspension (CS) formulation of S-metolachlor and a fenclorim seed treatment in rice. The first experiment assessed the tolerance of two cultivars (‘Diamond’ and ‘DG263L’) to three rates (0.42, 0.84, and 1.68 kg ai ha−1) of a CS S-metolachlor at a delayed preemergence (DPRE) application timing in conjunction with a fenclorim seed treatment. The second experiment evaluated a 1- to 2-leaf (EPOST) application of a CS S-metolachlor at 0.56 and 1.12 kg ai ha−1 to fenclorim-treated rice. Fenclorim reduced injury and partially protected rice yield when S-metolachlor was applied DPRE at 1.68 kg ai ha−1 in both years. However, in one year, under adverse conditions, rice yields were only 65% and 66% of the nontreated control for fenclorim-treated ‘Diamond’ and ‘DG263L’, respectively. An EPOST application of S-metolachlor at 1.12 kg ai ha−1 resulted in 44% to 51% visible injury 35 d after treatment. Relative rice yields were 88% and 89% of the nontreated weed-free treatment in 2022 and 2023, respectively. Fenclorim provided enhanced crop safety at both the 0.84 and 1.68 kg ai ha−1 rates of S-metolachlor. However, the potential for reduced yield can arise when unfavorable conditions occur soon after application. An EPOST application timing of CS S-metolachlor at 0.56 kg ai ha−1 may be a viable option in rice, but 1.12 kg ai ha−1 is too high on a silt loam soil, resulting in significant rice injury
Polarimetry Terahertz Imaging of Human Breast Cancer Surgical Specimens
Get PDFPurpose
We investigate terahertz (THz) polarimetry imaging of seven human breast cancer surgical specimens. The goal is to enhance image contrast between adjacent tissue types of cancer, healthy collagen, and fat in excised breast tumors. Based on the biological perception of random growth of cancer and invasion of surrounding healthy tissues in the breast, we hypothesize that cancerous cells interact with the THz electric field in a different manner compared with healthy cells. This difference can be best captured using multiple polarizations instead of single polarization.
Approach
Time domain pulsed signals are experimentally collected from each pixel of the specimen in horizontal–horizontal, vertical–horizontal, vertical–vertical, and horizontal–vertical polarizations. The time domain pulses are transformed to the frequency domain to obtain the power spectra and 16 Mueller matrix images. The whole-slide pathology imaging was used to interpret and label all images.
Results
The results of the cross and co-polarization power spectrum images demonstrated a strong dependency on the tissue orientation with respect to the emitted and detected electric fields. At the 130-deg rotation angle of the scanned samples, the detector showed the strongest reflected signal in cross-polarization. Furthermore, the Mueller matrix images consistently demonstrated patterns in fresh and block tissues confirming the differentiation between tissue types in breast tumor specimens.
Conclusions
THz polarimetry imaging shows a potential for improving image contrast in excised tumor tissues compared with single polarization imaging. Cross-polarization signals demonstrated smaller amplitudes compared with co-polarized signals. However, averaging the signal during measurements has tremendously improved the image. Furthermore, in post-processing, averaging the frequency domain images and the Mueller matrix elements with respect to frequency has led to better image contrast. Some patterns in the Mueller matrix images were difficult to interpret leading to the necessity of more investigation of the Mueller matrix and its physiological interpretation of breast tumor tissues
Effects of Fast and Slow-Wilting Soybean Genotypes on Plant-Herbivore Interactions
No full textSoybean [Glycine max (L.) Merr.] is one of the most important food crops in the world due to its multiple uses in agriculture sector. A major limiting factor in soybean production system is drought stress, causing up to 80% reduction in yield. Due to climate change and associated rise in ambient temperatures, water scarcity is a major concern in crop production, and consequently researchers are turning to soybean accessions that demonstrate better water use efficiency (WUE) traits. However, field grown soybean is also under severe pressure from insect herbivores, often accounting for a 30% reduction in yield. Among these, Soybean looper (Chrysodeixis includens, SBL) and fall armyworm (Spodoptera frugiperda, FAW) are two major pests and have been found to reduce soybean yield by feeding on both foliar and floral organs. The first part of this thesis aimed to investigate the impact of FAW feeding on soybean accessions that vary in their WUE traits, by examining FAW growth and life history parameters along with plant growth and response to FAW damage. Seventeen soybean accessions from the GRIN database provided by the USDA were grown in a greenhouse and exposed to feeding from second instar FAW for 48 hours at three different soybean growth stages: V3, R3, and R6. The growth and development of the soybean plants was monitored at each stage throughout the study. Once the soybean plants reached maturity, their pods were collected and counted. Following soybean exposure, the FAW were placed on artificial diet and allowed to pupate and emerge as adult FAW moths. Results showed that overall, fast wilting soybean accessions grow taller and have more leaves than slow wilting accessions, but slow wilting soybean accessions had a higher yield. Mid-stage (R3) soybean plants had the highest FAW mortality, but they gained the least mass on early stage (V3) soybean plants. FAW had higher mortality on fast wilting plants, potentially due to their increased trichome density. Overall, we observed significant variation in defense traits across soybean growth stages and wilting speeds with direct consequences on FAW development. The second part of this thesis focused on understanding the intersection of WUE and insect resistance traits when exposed to pulsating drought and herbivory by FAW and SBL larvae. Using fast and slow wilting soybean accessions, we examined the interaction between physiological traits associated with WUE and insect resistance traits and how they influence soybean yield. Results showed that the soybean plants exhibited overcompensation regarding growth and development, but slow wilting genotypes yielded higher quality pods and seeds. Overall, FAW fed at a significantly higher rate than SBL despite being less specialized to feed on soybean. Fast wilting accessions had a higher pod yield than slow wilting accessions; however, slow wilting plants produced heavier pods with larger seeds. In terms of germination, there was no significant difference across wilting speeds and treatments. These results advance our understanding in how plant insect-interactions at between soybeans with different wilting speeds various soybean growth stages can influence both FAW and SBL development. Overall, we show that different soybean wilting speeds have differential impacts on herbivore fitness. We also see that despite fast wilting plants overcompensating in terms of growth and pod production, slow wilting plants may still be more fit
Encapsulation of Probiotics by Cellulose Nanocrystal-Alginate Composite Beads for pH Stimuli-Responsive Delivery
Get PDFMicroencapsulation has garnered significant interest, with oral probiotics delivery systems showing enormous potential to help restore the gut microbiome. This method holds vast potential to protect and release specific microbial strains to the desired target site (i.e., colon) within the gastrointestinal tract (GIT). However, current encapsulation methodologies, utilizing either synthetic or biological materials as carriers, encounter challenges such as suboptimal encapsulation efficiency, premature probiotic release, and inadequate control over release kinetics. In this work, hydrogel microsphere (HM) composites of different cellulose nanocrystal (CNC) forms (i.e., colloidal (c), and crosslinked (x)) and alginate (ALG) were used as advanced controlled release systems (CRSs). These carrier systems effectively encapsulated and protected probiotic cells before releasing them to the desired target site within the GIT. E. coli Nissle 1917, a non-pathogenic gram-negative probiotic strain, was used as the model organism for encapsulation in the HMs. An empirical model based on response surface methodology (RSM) was developed to optimize and investigate the effect of flow rate, cell concentration, and weight ratio of cCNC/ALG and xCNC/ALG on sphericity of probiotics encapsulated HMs. The in-vitro release behavior of various optimized probiotics encapsulated HMs was studied by sequential incubation in simulated gastric fluid (SGF, pH ~2.4) and simulated intestinal fluid (SIF, pH ~7.4), mimicking the natural journey through the GIT. Experimental results indicated that cCNC/ALG and xCNC/ALG HMs maintained stability in acidic conditions (pH ~2.4), retaining over 90% of encapsulated probiotics after 2 hours of incubation in SGF. In contrast, both types of HMs gradually released the cells in alkaline pH, facilitating the controlled release of encapsulated probiotics. These findings underscore the innovative potential of composite HMs to revolutionize targeted probiotic delivery systems in the GIT, addressing longstanding challenges in encapsulation and controlled release
Synthesis and Process Optimization of Cellulose Nanocrystals from \u3ci\u3eMiscanthus x. giganteus\u3c/i\u3e for Commercial Viability
Get PDFCellulose nanocrystals (CNCs), derivatives of an abundant biopolymer, i.e., cellulose, are emerging as promising alternatives to petrochemical-based products due to their unique properties, including biodegradability, low toxicity, high strength, low density, large surface area and low coefficient of expansion. CNCs have diverse applications ranging from food packaging and textiles to drug delivery and medical implants, etc. Despite their potential, the widespread commercialization of CNCs faces significant hurdles owing to the high environmental burden and production costs. They are mainly driven by the commonly used source utilized for CNC synthesis i.e., wood and the intensive synthesis process i.e., requirement of pretreatments before pulping followed by strong sulfuric acid hydrolysis. Therefore, to enhance the commercial viability of CNCs, it is essential to reduce pretreatment requirements, optimize acid hydrolysis process, along with utilizing an alternative source with favorable properties. In our study, we investigated the potential of Miscanthus x. giganteus (MxG), a non-wood lignocellulosic biomass, as an alternative cellulose source for CNC production due to its excellent intrinsic properties, such as low lignin content, high cellulose content, and loosely bound fibers. In the first objective, we investigated the requirement of pretreatment prior to pulping followed by optimizing the sulfuric acid hydrolysis process for efficient CNC production. The study revealed that, in comparison to our in-house wood-based optimized process, the optimized sulfuric acid-based CNC synthesis process from MxG yielded high-quality CNCs with substantially higher yield and offered environmental and economic benefits. The second objective investigated a mixed acid hydrolysis method, combining sulfuric acid and acetic acid, a recyclable organic acid, for CNC production from MxG. While the mixed acid process produced lower CNC yields than the optimized sulfuric acid method, environmental and economic assessments highlighted its drawbacks due to higher usage of acids, raw materials and utilities. Conclusively, our study established MxG as a promising and sustainable alternative to traditional wood-based cellulose sources for CNC production, with sulfuric acid-based synthesis method as a more efficient option than the mixed acid hydrolysis approach. These findings represent a crucial step towards scalable CNC production, supporting their potential for widespread applications. Further optimization of the synthesis process has the potential to enhance production efficiency, reduce costs, and lower environmental impacts, thereby facilitating the commercial success of CNCs
Modeling, Synthesis, and Experimental Characterization of Rhenium Disulfide for Optoelectronic Devices
Get PDFTwo-dimensional (2D) transition metal dichalcogenides (TMDs) have garnered considerable interest for their potential in optoelectronics and photonics owing to their remarkable combination of electronic, optical, and mechanical properties. These characteristics distinguish them from other 2D materials, including graphene, making them particularly valuable for next-generation technologies. This dissertation focuses on ReS₂, a 2D TMD with a unique anisotropic 1T distorted crystal structure. The research aims to elucidate its fundamental properties through a combination of theoretical modeling, material synthesis, and experimental characterization techniques, with the goal of optimizing ReS₂ for device applications. A theoretical investigation utilizing Density Functional Theory (DFT) calculations was conducted to examine the electronic band structure, optical properties, and vibrational modes of Rhenium Disulfide (ReS₂). Specifically, the calculations predicted a bandgap of 1.35 eV and 1.43 eV for bulk and monolayer ReS₂ respectively. Furthermore, the phonon dispersion at the Γ point was identified within the range of 130 cm⁻¹ to approximately 430 cm⁻¹. In parallel with the theoretical investigation, high-quality ReS₂ flakes were synthesized using chemical vapor deposition (CVD) on silica and SiO₂/Si. The synthesized ReS₂ samples were experimentally characterized using a range of spectroscopic and microscopic techniques. The structural integrity of the grown samples was validated through X-ray diffraction (XRD), while Scanning Electron Microscopy coupled with Energy Dispersive X-ray Spectroscopy (SEM-EDS) was employed to analyze the elemental composition. Photoluminescence spectra showed excitonic features associated with interband transitions in both monolayer flakes and bulk-like structures. The DFT calculations and experimental measurements of Raman scattering spectrum were comparable. The optical absorbance spectrum of ReS₂ flakes grown on a silica substrate exhibited excitonic features at room temperature
Blend Matters: Interactions of Rice Cultivars on Milling, Physico-chemical & End Use Traits
Get PDFRice blending or mixing of different rice cultivars, a common practice in the industry, significantly impacts processing efficiency and end-product quality, yet its effects on end products remain understudied. This research investigated the implications of blending contemporary Arkansas rice cultivars through two comprehensive studies focusing on milling yields and physicochemical properties, instantization, and parboiling processes. Five long-grain cultivars, including hybrids (RT 7521 FP, RT 7321 FP, XP 753) and purelines (Ozark, CLL 16), were blended in various combinations and different drying. The first study revealed that blending significantly affected milling yields and physicochemical attributes. Pre-drying blending yielded better results compared to post drying blending. Individual cultivars showed varied head rice yields (47.27% for RT 7321 FP and 58.60% for XP753), while blended hybrid cultivars yielded around 52%. Blending affected pasting properties, with hybrid cultivars showing decreased viscosities when blended. Cooking durations varied among cultivars and blends; RT 7521 FP had a 26–minute duration, reduced to 21–22 minutes when blended. The second study focused on instantization and parboiling processes. For instantization, percentage point moisture removal varied significantly (24.32–47.44%) across blends, with the Hybrid + Pureline blend showing superior and consistent moisture removal. Color stability varied among blends, with ΔE values ranging from 4.49–7.06 for individual cultivars and 5.78–6.90 for the Hybrid + Pureline blend. In parboiling, the Hybrid + Pureline blend exhibited the highest milling yields (MRY: 72.23–73.50%, HRY: 70.33–71.37%). Post-drying blending resulted in higher parboiling yields compared to pre-drying blending. The results demonstrate that strategic blending can enhance processing efficiency and product quality, though outcomes vary depending on the specific cultivar combinations and processing methods. These findings provide valuable insights for optimizing blending strategies in rice processing operations, particularly for end products like instant and parboiled rice