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Methylglyoxal Influences Development of Caenorhabditis Elegans via Heterochronic PathwayWang, Jiaying 11 July 2017 (has links)
Methylglyoxal is a highly reactive dicarbonyl compound, which is widely distributed in food products and beverages, and is particularly high in Manuka honey. In addition to its antibacterial effects, methylglyoxal is also known as a major precursor of advanced glycation end products (AGEs), that produces altered macromolecules (such as proteins and DNA), leading to abnormal physiological changes. However, the effects of methylglyoxal on development is unclear. Thus, this study aimed to determine the role of methylglyoxal in this aspect using Caenorhabditis elegans (C. elegans). Treatment of methylglyoxal at 0.1 mM and 1 mM for 48 h significantly inhibited development of C. elegans and reduced pumping rate. Activity, measured by moving speed, was increased with 0.1 mM methylglyoxal, but reduced with 1 mM methylglyoxal. Lifespan of C. elegans was not influenced by methylglyoxal at 0.1 mM, but was shortened at 1 mM. Treatment methylglyoxal on the mutant, lin-41, which has a precocious phenotype, could alleviate the implication on wild-type worms. These results suggested that methylglyoxal significantly influenced the development of C. elegans through the heterochronic pathway.
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SODIUM REDUCTION IN TURKEY BREAST MEAT BY USING SODIUM ANION SPECIESPandya, Janamkumar 24 March 2017 (has links) (PDF)
Research studies show that an average American consumes 3,400 to 4,500 mg/day of sodium in their diet against the dietary recommendation of 1,500 to 2,300 mg/day. The majority of this sodium comes from processed foods. Excess sodium in the diet can potentially cause health issues such as hypertension, heart attack, kidney failure, and bone problems. The objective of this study is to understand sodium diffusion in a protein model using turkey breast meat and determine the opportunities of its reduction by changing the process conditions and combining table salt with other sodium salts.
Since proteins are a complicated system and there are very few research studies available on meat in this area, it is necessary to understand the trend of sodium diffusion in the meat while cooking in presence of salt at different temperatures followed by analyzing the change in the diffusion in presence of different sodium salts with anions larger than sodium chloride. Since protein denaturation can have impact on the diffusion process, the denaturation profile for turkey breast meat protein was analyzed by Differential Scanning Colorimetry (DSC). The DSC results were visually confirmed by SEM analysis. After obtaining results from DSC and SEM analysis, the processing temperature of 4oC, 23oC, 50oC, 70oC and 90oC was implemented to obtain the diffusion trend before, during, and after protein denaturation. 1-inch meat cubes were cooked in 5% (0.86M/L) salt solution at different time and temperature combinations. Sodium analysis was performed on Ion Selective Electrode (ISE) and the results were confirmed by ICP-OES. This study showed that the sodium content of the processed samples was not proportional to the treatment temperature.
The Study was also conducted to analyze the effects of sodium salts with larger anions than sodium chloride on sodium diffusion during thermal applications. Sodium Phosphate, Sodium Tripolyphosphate, Sodium Sulfate and Monosodium Glutamate were incorporated in the study. Sodium content in the samples processed in this salts showed 32-46% reduction compared to those processed in sodium chloride. Since sodium phosphate is widely used in the meat industry, it may have the most potential to partially replace salt. Texture analysis was performed on the samples cooked in sodium chloride and sodium phosphate solutions in order to determine changes in textural properties. A brief sensory test was also conducted with 10 participants to investigate the preference of sodium phosphate incorporation in the meat and to identify any after taste.
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The Comparison of Functional and Physical Properties of Commercial Pulse Proteins to Soy ProteinMa, Kai Kai 01 September 2020 (has links) (PDF)
There has been growing interest in the utilization of plant-derived proteins as functional ingredients in many food and beverage applications because they are perceived as being more sustainable, healthy, and ethical than animal-derived proteins by many consumers. Traditionally, soy proteins have been the most widely employed plant protein in the food industry. However, a number of alternative plant-based protein sources have recently become available, with pulse proteins being one of the most popular. In this study, the physicochemical properties and functional attributes of various commercially available pulse protein isolates were compared with those of soy protein isolate to evaluate their potential application in foods and beverages. The water holding capacity, oil holding capacity, gelation properties, emulsifying properties, and color of faba bean (FPI), pea (PPI), lentil (LPI), and soy (SPI) protein isolates were therefore measured. SPI had a significantly higher water holding capacity (7.6 g/g) than the pulse protein isolates (2.2-5.1 g/g). Among the plant protein isolates, PPI had a significantly lower oil holding capacity and gelling property. LPI was more effective at producing small oil droplet sizes during homogenization than the other protein isolates. Nevertheless, all of the plant proteins were capable of forming relatively small oil droplets (D32 = 1-3 mm) at a protein-to-oil ratio of 1:10. As expected, droplet size decreased with increasing protein concentration for all plant protein isolates, which increased their resistance to creaming. These results suggest that pulse proteins may have similar or better techno-functional properties than soy proteins for certain applications. In particular, lentil proteins were more effective emulsifiers, whereas faba bean proteins were more effective gelling agents. These proteins may therefore be suitable for application in plant-based milks, eggs, cheese, or meats where emulsifying or gelling properties are required.
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ANTI-INFLAMMATORY EFFECT OF RED SEAWEED EXTRACTSYang, Yingying 01 September 2020 (has links) (PDF)
Red seaweeds are reported to represent the largest group of algae, with more species accounted for than the combination of brown and green seaweeds. Due to the high amount of polysaccharides in red seaweeds, they are mainly utilized for commercial agar and carrageenan production in industry. However, increasing studies indicate other valuable compounds such as lipids and polyphenols could be potential utilized for multiple human needs (e.g., drug development) (1, 2). With increasing studies demonstrating the potential health benefits of seaweed components, two red seaweed species commonly consumed in Asia, hong qı´ lı´n c a`i (HQL), Eucheuma sp and zhe` gu¯ ca`i (ZGC), Caloglossa leprieurii, were investigated on to determine the anti-inflammatory effects of their extractable lipophilic bioactives (ELB) and bound lipophilic bioactives (BLB) in lipopolysaccharide( LPS)-treated RAW 264.7 macrophages. The chemical composition of ELB and BLB was characterized in terms of total phenolic content (TPC), total flavonoid content (TFC), total tannin content (TTC), oxygen radical absorbance capacity (ORAC), and etc. Six phenolic compounds were identified in ZGC extracts and one was detected in HQL. All extracts inhibited the nitric oxide (NO) production in LPS-induced macrophages, which was associated with downregulation of iNOS and COX-2 protein expression and up-regulation of HQ-1 and NQO1 protein expression. Overall, our results showed that both ELB and BLB in HQL and ZGC seaweeds presented potential anti-inflammatory activities. These results warrant future investigations to determine the mode of actions of red seaweed bioactives and their efficacy in humans.
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Optimization of Optical Properties of Plant-Based FoodsWannasin, Donpon 01 September 2023 (has links) (PDF)
Plant-based foods are considered to be more sustainable food source than animal-based foods due to their lower environmental impact. However, there is a challenge in producing plant-based foods with similar taste, texture, and appearance to animal-based products to meet consumers expectations. The appearance, which includes color, is the first sensory attribute consumers experience of foods, and so it influences consumers’ buying decisions. Food colorants are added to match the color of plant-based foods with animal-based ones. The food colorant choice is shifting toward natural colorants due to their perceived health benefits and clean-label aspects. Therefore, this study aimed to optimize the optical properties of plant-based foods using natural food colorants. Initially, the impact of natural pigments that selectively absorb light (turmeric, red beet, and butterfly pea flower) and colloidal particles that selectively scatter light (oil droplets) on the optical properties of model plant-based oil-in-water emulsions was investigated. It was found the pigment and oil droplet characteristics, including pigment type and concentration, and droplet size and concentration, could be adjusted to modulate the chromaticness or lightness of emulsions by altering light absorption and scattering effects. This knowledge is useful to optimizing the appearance of plant-based foods by adjusting these parameters. Then, natural pigments with three primary colors (yellow, red, and blue) were blended to mimic the color of animal-based products (raw meat, cooked meats, egg, and cheese). A color matching model developed from Kubelka-Munk and color theories was then used to determine the optimum ratio of each colorant needed to match the spectral reflectance of animal-based products. The methodology developed was able to optimize the color of model plant-based emulsions to that of different food matrices. The improved understanding of the optical properties of natural pigments and color matching theory developed in this study should help to formulate plant-based foods with more similar appearances to animal-based products, thereby increasing consumers’ acceptance of plant-based foods.
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Spray Fabrication of Layer-by-Layer Antimicrobial N-Halamine CoatingsDenis-Rohr, Anna 17 July 2015 (has links) (PDF)
Antimicrobial coatings in which the active agent (e.g. N-halamine) can regenerate activity represent a promising way to prevent microbial cross-contamination. A reported method for applying coatings containing antimicrobial N-halamines is layer-by-layer (LbL) application of polyelectrolytes, which form N-halamines upon cross-linking. Prior reports on dip layer-by-layer (LbL) fabrication have demonstrated the potential of this coating technology; however, spray LbL fabrication would enable more rapid coating and represents a more commercially translatable application technique. In this work, dip and spray LbL methods were used to coat polypropylene (PP) with N-halamine containing bilayers consisting of cross-linked polyethylenimine (PEI) and poly(acrylic acid) (PAA). Further experimentation with spray LbL fabrication used naturally occurring polyelectrolytes, chitosan and alginate. Materials were characterized using atomic force microscopy (AFM), ellipsometry, contact angle, fourier transform infrared spectroscopy, a chlorine content assay, and a dye assay for amine quantification. All methods of coating application exhibited a 99.999% (5-log) reduction against Listeria monocytogenes with application time for spray LbL taking less than 10% of the time required for dip LbL. Spray LbL fabrication of N-halamines is a rapid and inexpensive method to fabricate rechargeable antimicrobial surfaces.
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EFFECT OF AMYLOSE AND PROTEIN OXIDATION ON THE THERMAL, RHEOLOGICAL, STRUCTURAL, AND DIGESTIVE PROPERTIES OF WAXY AND COMMON RICE FLOURS AND STARCHESLiu, Jing 01 January 2013 (has links)
The effects of oxidation by sodium hypochlorite (0, 0.8, 2, and 5%, NaOCl), the presence of endogenous proteins, and amylose content on waxy and common rice flours (WF, CF) and starches (WS, CS) were investigated in terms of in vitro starch digestibility, morphology and surface properties, and thermal and rheological characteristics.
The concentration of NaOCl had an effect on all the samples including WF, CF, WS, and CS. The carbonyl and carboxyl group contents increased up to 25 and 10 folds (P < 0.05) of oxidized starches (WS, CS), respectively. Only mild oxidation (P < 0.05) occurred in flours (WF, WS). In addition, endogenous proteins were oxidized according to amino acid analysis and SDS–PAGE results. Glu+Gln, Gly, His, Arg, Tyr, and Lys were more sensitive to NaOCl oxidation. Disulfide bonds, hydrophobic force, and hydrogen bonds were involved in protein polymerization after NaOCl oxidative modification. In granular state, the in vitro starch digestibility of WF, WS, and CS decreased by 5% NaOCl oxidation. After gelatinization, only 2 and 5% oxidized WS had lower digestibility.
Scanning electron microscopy and confocal laser scanning microscopy further demonstrated that protein existed on the surface of starch granules and had aggregation by oxidation. X-ray diffraction patterns showed the crystallinity of 5% oxidized flours and starches was reduced compared with all their non-oxidized samples.
Thermal and rheological properties were analyzed by differential scanning calorimetry and rheometer, respectively. Starch gelatinization peak temperature of flours (WF, RF) was increased by 3 °C, but starches (WS, CS) had a significantly decrease by 8 °C. Viscoelastic patterns were dramatically changed by oxidation. Oxidized WF and CF had increased in both viscosity and elasticity by oxidation, whereas both WS and CS had significantly lower viscoelasticity after oxidative modification.
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INFLUENCE OF DIETARY RACTOPAMINE AND SUPRANUTRITIONAL SUPPLEMENTATION OF VITAMIN E ON PROTEOME PROFILE OF POSTMORTEM BEEF LONGISSIMUS LUMBORUM MUSCLEKim, Hyun Mok 01 January 2018 (has links)
The effects of dietary ingredients on the proteome profile of postmortem beef longissimus lumborum (LL) muscle were evaluated. In the first experiment, the influence of dietary ractopamine on the whole-muscle proteome of beef LL was examined. Five proteins were differentially abundant between ractopamine-fed (RAC) and non-ractopamine fed (CON) groups. The differentially abundant proteins were over-abundant in RAC and were related to muscle structure development (F-actin-capping protein subunit beta-2 and PDZ and LIM domain protein-3), chaperone (heat shock protein beta-1), oxygen transportation (myoglobin), and glycolysis (L-lactate dehydrogenase A chain). These findings indicated that ractopamine influences the abundance of proteins associated with muscle structure and fiber type shift in beef LL.
In the second experiment, the effect of Vitamin E supplementation on the sarcoplasmic proteome of beef LL was characterized. Five differentially abundant proteins were observed between vitamin E-supplemented (VITE) and non-vitamin E-supplemented (CONT) groups. All the differentially proteins were over-abundant in CONT and were associated with antioxidant activity (thioredoxin-dependent peroxide reductase, peroxiredoxin-6, and serum albumin) and glycolysis (beta-enolase and triosephosphate isomerase). These results indicated that the strong antioxidant activity of vitamin E leads to low expression of antioxidant proteins and antioxidant-related glycolytic enzymes in beef LL muscle.
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Effects of Milk Processing on the Milk Fat Globule Membrane ConstituentsElías-Argote, Xiomara E 01 July 2011 (has links)
ABSTRACT
Effects of Milk Processing on the Milk Fat Globule Membrane Constituents
Xiomara E. Elías-Argote
The milk fat globule membrane (MFGM) is avidly studied by many groups of scientists around the world due to its unprecedented nutritional and functional properties; however, limited research has been performed on the effects of milk processing on the chemical changes of the MFGM. Thus, this study highlights the changes that lipids and proteins undergo from the time milk leaves cow’s udders. Cooling (4 °C) was included along with subsequent pasteurization by different traditional thermal processes and cold pasteurization by pulse light ultra violet treatment. Cooling milk to 4 °C had a measureable effect on the MFGM composition, resulting in protein alterations, particularly to butyrophilin and adipophilin. Thermal treatments disturbed the native structures of molecules and increased the adsorption of milk and whey proteins on the globules, especially a-lactalbumin and b-lactoglobulin. As the heat intensity increased, the aggregation of fat globules became more pronounced due to protein interactions. Intrinsic MFGM proteins also varied in relative abundance during the processing steps. The concentrations of polar lipids did not change during processing, with the exception of phosphatidylserine, which decreased during the cooling and thermal treatments. Cold pasteurization (UV treatment) had a minimal effect on fat globules and MFGM proteins. Since the MFGM promises to deliver nutritional effects and more when included in food products, currently HTST pasteurization was shown to be the best method to process milk and obtain MFGM isolates for further supplementation.
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The Use of Elemental Databases in Forensic Science: Studies on Vehicle Glass Interpretation and Milk Powder ProvenancingHoffman, Tricia Marie 30 May 2018 (has links)
The first study focuses on the development of a laser based method for the elemental analysis of solid milk powder. Milk powder samples originating from five different countries were analyzed to determine any geographic differences. A LA-ICP-MS method was developed and compared to k0-INAA for several milk samples as well as a reference sample. Precision of 10% RSD or better and a bias of 10% was achieved for both techniques for most elements with LA-ICP-MS producing lower limits of detection (~ 1 ppm) for Sr. The comparison of LA-ICP-MS to k0-INAA showed overlap of the 95% confidence intervals for all comparison samples. The data for 68 authentic milk powder samples representing 5 different countries (Argentina, Russia, Singapore, Slovenia, and the United States) was collected and used as a preliminary database. Principle component analysis (PCA) shows different groupings for the United States, Argentina, Singapore, and Slovenia. However the large number and geographic distribution of samples from Russia were not able to be distinguished from the samples from the United States and Slovenia.
The second study focuses on the use of trace element databases for the objective interpretation of forensic glass evidence. Ten laboratories conducting analysis of glass participated in three inter-laboratory exercises. The aims of these exercises were to evaluate the use of a standard method for the analysis and comparison of glass evidence and to investigate different statistical approaches for interpreting results. Elemental analysis was performed on 420 vehicle windshield samples collected from 210 different vehicles representing manufacturing dates between 2004-2017 and 26 vehicle manufacturers. Using a variation of a previously reported comparison criterion for comparing samples to a database, the false exclusion rate and false inclusion rate for the new vehicle database were calculated to be 1.9% and 0.1 % respectively. This criterion was used to calculate the frequency of an elemental profile for the case scenarios distributed as part of the inter-laboratory exercises. Similarities were observed between labs that calibrated their data the same way, thus showing it is possible for labs to use a central database.
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