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The Use of Ionic Liquid for the Pretreatment of Energy Cane BagasseQiu, Zenghui 15 November 2012 (has links)
Lignocellulosic biomass appears to be a prospective renewable resource that can be used for the generation of biofuels and bioproducts. The major concern in lignocellulose conversion is overcoming biomass recalcitrance through pretreatment while still maintaining a green, energy efficient and cost-effective process. Energy cane is a promising energy crop with high fiber content, cold tolerance, and less fertilizer and water input requirements as compared to conventional sugarcane. Ionic liquids (ILs) are promising solvents for the pretreatment of lignocellulose as they are thermally stable, environmentally friendly, recyclable, and have low volatility. This study assessed the use of ionic liquid 1-ethyl-3-methylimidazolium acetate ([EMIM][OAc]) as a solvent during the pretreatment of energy cane bagasse (ECB) and its effect on the chemical composition, surface morphology, cellulose crystallinity, and enzymatic hydrolysis of the pretreated biomass.
IL-treated ECB resulted in significant lignin removal (32.1%) with slight glucan and xylan losses (8.8% and 14.0%, respectively), and exhibited much higher cellulose and hemicellulose enzymatic digestibilities (87.0%, 64.3%) than untreated (5.5%, 2.8%) or water-treated (4.0%, 2.1%) ECB, respectively. The enhanced digestibilities of IL-treated biomass can be attributed to delignification and reduction of cellulose crystallinity as confirmed by FTIR and XRD analysis. When pretreating ECB with recycled IL, enzymatic digestibility decreased as the number of pretreatment recycles increased. Decreasing the pretreatment temperature from 120 °C to 100 °C and extending the residence time from 30 min to 2 h brought significant improvement to the pretreatment efficiency of recycled [EMIM][OAc] on ECB. However, response surface methodology model indicated that a higher glucose yield of IL-treated biomass could be obtained at higher pretreatment temperatures with shorter residence times. The optimal processing conditions were pretreatment of ECB at 131.9 °C for 28.1 min at 8.4% solids loading resulting in a final glucose yield of 35.96 g glucose per 100 g of native biomass.
The results presented in this thesis demonstrated that [EMIM][OAc] can be used as a potential solvent for the pretreatment of lignocellulosic biomass such as ECB. Furthermore, the sugar yields obtained post pretreatment have great potential as building blocks in the production of renewable fuels and chemicals.
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Inhibition of Adipocyte Differentiation in 3T3-L1 Cell Line by Quercetin or Isorhamnetin.Carvajal-Aldaz, Diana Gabriela 15 November 2012 (has links)
Carvajal-Aldaz, Diana Gabriela, B.S. Food Science, Zamorano University, 2007
Master of Science, Fall Commencement, 2012
Major: Food Science
Inhibition of Adipocyte Differentiation in 3T3-L1 Cell Line by Quercetin or Isorhamnetin
Thesis directed by Professor Jack N. Losso
Pages in thesis, 43. Words in abstract, 281.
ABSTRACT
Obesity has become a major health problem worldwide. Obesity increases the risk of hypertension, diabetes, and certain types of cancer. Quercetin is a bioactive compound widely found in a variety of foods that are consumed daily. Isorhamnetin is a bioactive compound found in some foods and also is a quercetin metabolite. Many studies have reported the anti-obesity and anti-inflammation properties of quercetin and isorhamnetin. The objective of this study was to test the effect of quercetin or isorhamnetin at physiological and supraphysiological concentrations on the inhibition of the differentiation process of 3T3-L1 pre-adipocyte to adipocyte. Cell viability results demonstrated no significant difference (P > 0.05) between non differentiated cells, control and quercetin or isorhamnetin treated cells. During adipocyte differentiation for 8 days in the presence of quercetin or isorhamnetin, cell viability was above 94.84% and 97.63%, respectively. Red oil O staining assay was performed in order to evaluate the inhibitory effect of quercetin or isorhamnetin on cytoplasmic lipid droplet accumulation. Significant differences (P < 0.05) were reported. Isorhamnetin was more effective than quercetin in inhibiting cytoplasmic lipid droplet accumulation. Neither quercetin nor isorhamnetin had an effect on the expression of macrophage chemoattractant protein -1 (MCP-1). CCAAT/enhancer binding protein α (C/EBP-α) was down-regulated by quercetin or isorhamnetin. Compared to control quercetin decreased PPAR-γ 1 and 2 expressions by 45.03 ± 3.17% and 27.58 ± 12.39%, while isorhamnetin decreased PPAR-γ 1 and 2 expressions by 41.48 ± 9.51% and 2.01 ± 32.46%, respectively. β-catenin was not dose dependent either for quercetin or isorhamnetin and did not follow a specific trend. Taken together, our data indicate that isorhamnetin more than quercetin can exert potential anti-obesity effects by inhibiting differentiation of pre-adipocytes at physiological concentrations.
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Effect of Surfactants on the Pretreatment of Sugarcane Bagasse with Dilute AmmoniaCao, Shuo 20 November 2012 (has links)
Lignocellulosic biomass is composed of cellulose, hemicellulose and lignin which are not readily available for conversion in their native form. It is widely accepted that lignin acts as the glue that binds cellulose and hemicellulose, giving rigidity and resistance to lignocellulose. The use of non-ionic surfactants during pretreatment can help alter the structure of lignocellulosic biomass to improve cellulose digestibility and ethanol yields.
Tween 80, Tween 20, PEG 4000, or PEG 6000 was used with ammonium hydroxide for the pretreatment of sugarcane bagasse. The pretreatment was carried out by mixing sugarcane bagasse, ammonium hydroxide (28% v/v) and water at a ratio of 1: 0.5: 20, adding 3% (w/w) surfactant based on the weight of dry biomass, and heating the mixture to 160 °C for 1 h. The final concentration of ammonium hydroxide was 0.65% w/w at 4.7% solids loading. Chemical compositions were determined before and after pretreatment. Fibers were hydrolyzed using commercial enzymes, Spezyme CP and Novozyme 188. Fermentable sugars and ethanol concentrations were analyzed by HPLC. The results indicated that PEG 4000 and Tween 80 gave the highest cellulose digestibilities (62%, 66%) and ethanol yields (73%, 69 %), respectively.
Tween 80 was selected over PEG 4000 because of its low cost. The effect of two concentrations of ammonium hydroxide 0.26% w/w (1: 0.2: 20, biomass: ammonium hydroxide: water ratio) and 0.65% w/w (1: 0.5: 20, biomass: ammonium hydroxide: water ratio), and Tween 80 (1.5%, 3% and 5% w/w, based on the weight of dry biomass) were evaluated during pretreatment at 4.7% solids loading. The greatest lignin removal (37%), cellulose digestibility (66%) and hemicellulose digestibility (43%) were observed at 1: 0.5: 20 ratio supplemented with 3% (w/w) Tween 80. These pretreatment parameters were selected for scale-up experiments at a higher solids loading (10.5%) in a 20 L bioreactor. The greatest lignin removal (55%), cellulose digestibility (72%) and hemicellulose digestibility (57%) were observed with 3% Tween 80-dilute ammonia pretreatment at 1: 0.5: 8 ratio with a final concentration of ammonium hydroxide of 1.47% w/w. Morphological changes in the structure of non-ionic surfactant-dilute ammonia pretreated sugarcane bagasse were observed.
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Development and Evaluation of Molecular-Based Assays for Detecting Salmonella Serovars in Various Food CommoditiesYang, Qianru 03 July 2013 (has links)
As a leading cause of foodborne illnesses and outbreaks, Salmonella poses a major public health risk in the United States and worldwide. Various food commodities including meat and poultry, eggs, and fresh produce can serve as the transmission vehicles for Salmonella infections. To better ensure the safety of these products and protect public health, rapid, accurate, and reliable detection methods for Salmonella are needed. Molecular-based methods like loop-mediated isothermal amplification (LAMP), have gained wide applications in Salmonella detection, owning to their rapidity, specificity, and sensitivity. However, there is a paucity of data on the robustness of these assays. And very recently, bioluminescence assay in real-time (BART) was used as a new and effective platform to detect LAMP products, and this combination has not been evaluated before.
This dissertation research evaluated the robustness of two LAMP assays in comparison with PCR, examined the application of LAMP assays in detecting Salmonella specifically in food items, and developed a novel LAMP-BART assay for Salmonella detection. The LAMP assays achieved robust detection of Salmonella under abusive preparation and running temperatures, also demonstrated greater tolerance than PCR to various inhibitors. They achieved 100% accuracy among 185 strains. The limits of detection of LAMP for Salmonella strains belonging to ten serovars were 1 to 10 cells per reaction in pure culture, 100-fold more sensitive than PCR. In spiked egg homogenates, it could detect Salmonella serovars Enteritidis and Typhimurium down to 10^4 CFU/25 ml egg homogenates directly and 1 CFU/25 ml with 8 h enrichment. In spiked produce (cantaloupe, jalapeno pepper, tomatoes, sprouts, and lettuces), the detection limits ranged from 10^4 to 10^6 CFU/25 g produce, which were comparable to qPCR. Coupled with 6 to 8 h of enrichment, LAMP consistently detected in produce samples spiked with very low levels of Salmonella cells, with the exception of sprouts.
Based on these evaluations and further development, LAMP demonstrated to be a rapid and robust alternative to PCR-based assays for Salmonella detection and could be adopted by food industries and regulatory agencies in routine product testing for Salmonella to improve product safety and protect public health.
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Differential Effect of 14 Free Fatty Acids in the Expression of Inflammation Biomarkers on Human Coronary Arterial CellsSoto Rodriguez Gil, Adriana 07 July 2013 (has links)
Cardiovascular disease is the leading cause of death in the US, and circulating free fatty acids (FFAs) are known risk factors associated with cardiovascular inflammation. The influence of 14 dietary FFAs (including saturated, mono-, poly-unsaturated and trans), on the expression of inflammatory markers in human coronary arterial smooth muscle (HACSM) and endothelial (HCAEC) cells using a cell culture model was investigated. HACSM and HCAEC cell cultures were incubated with 200 μM of each FFA for 8 or 24 h respectively at 37 °C in a 5% CO2 humidified incubator. Inflammatory biomarkers were assessed by ELISA or Western Blot in the supernatant or cell lysates respectively. Results showed significant differences in the expression of inflammatory biomarkers among the fatty acid treatments and the control, with myristic and palmitic acids being identified as the most and linoleic acid as the least pro-inflammatory. This confirms that FFAs can induce low-grade inflammation in human coronary arterial cells and provides more information on mode of action.
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Potential Influence of Blueberry and Black Raspberry Pomace Phenolics on Inflammatory Cytokines in Coronary CellsSoto Rodriguez Gil, Adriana 11 July 2013 (has links)
Elevated free fatty acids (FFAs) in obesity are known risk factors associated with chronic inflammatory conditions including cardiovascular inflammation and thus cardiovascular disease (CVD), the leading cause of death in the US. Anthocyanins from berries have the potential to provide protection against inflammation in various tissues; however they are poorly absorbed and undergo major transformations by the microbiome. The work presented in this dissertation involves the development and utilization of an in vitro model to characterize the products of colonic fermentation and absorption of blueberry and black raspberry pomace phenolics, and evaluate the potential efficacy of these products compared to anthocyanin-rich extracts as anti-inflammatory compounds in fatty acid-induced inflammation. A previous study identified myristic and palmitic acids as the most inflammatory, and linoleic acid as least inflammatory. In the first study, a model of colonic fermentation and transport through Caco-2 cells was used to evaluate the changes in phenolic profile of blueberry and black raspberry pomaces. Phenolic acids deriving from anthocyanin degradation were identified as the major products of berry pomace digestion and absorption. The second study involved the use of palmitic acid-stimulated HCAE and HCASM cells to evaluate the anti-inflammatory properties of anthocyanin-rich extracts and phenolic acids produced by microbiota fermentation and transport across Caco-2 monolayers using the prevention and intervention approaches. Protein and gene expression of inflammation markers demonstrate that phenolic acids derived from fermentation and absorption of both blueberry and black raspberry pomaces were equally or more effective than anthocyanin-rich extracts in modulating the inflammatory response through a proposed effect on NF-κB transcription, especially when used in the prevention approach. This suggests that phenolic acids may be responsible for some of the beneficial effects of blueberries and black raspberries. We have also demonstrated that berry pomaces, could be utilized in foods, providing anthocyanins and phenolic acids that may prevent inflammation in cardiovascular cells.
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Treatments to Reduce the Risk of Vibrio Species In Vitro and in Shucked OystersScott, Ronson Renard 11 July 2013 (has links)
"Vibrio parahaemolyticus" (Vp) and "Vibrio vulnificus" (Vv) are halophilic bacteria naturally occurring in estuarine environments that may concentrate in filter feeding shellfish. Consumption of raw or under-cooked seafood contaminated with Vp or Vv may lead to the development of acute gastroenteritis or fatal septicemia in at-risk individuals, respectively. This research encompassed two separate but related projects: evaluation of a low temperature pasteurization (LTP) technique for the reduction of Vp and Vv in commercial quantities of shucked oysters (SO) and the investigation of the efficacy of a citrus fruit extract, BIOSECUR® F440D in reducing/eliminating Vv in vitro.
Commercially available SO ("Crassostrea virginica"), artificially contaminated with pure Vibrio pathogens (3 ml) were used for evaluation of a LTP technique. Pure Vv cultures were used to test citrus extract. Vibrio vulnificus agar (VVA) with either 2% or 3% (mg/l) NaCl was used for plating Vv and Vp, respectively. The heat treatments of 40°C and 45° C reduced bacterial counts, however cultures survived even after 24 and 48 h of refrigeration (temperatures above freezing). Vv was more heat sensitive than Vp at 40°C and 45°C, with average bacterial counts of 4.9 and 6.0 log CFU/g without refrigeration, respectively. Unheated samples indicated that simple refrigeration is not adequate to reduce Vv and Vp in SO, as then was only a 0.79 and 0.61-log reduction, respectively. Both Vibrio species were reduced to non-detectable (ND) levels with and without refrigeration at treatments of 50°C and 55°C, making them the most effective treatments at 0, 24, and 48 h.
BIOSECUR® F440D at 0.5%, 1.0%, 1.5%, and 2.0% concentrations were used to determine the lowest effective concentration needed to achieve a significant log reduction of Vv. The 2.0%, 1.5% and 1.0% concentrations reduced Vv levels significantly (ND, 5.45, and 3.85 log-reduction, respectively). The 0.5% concentration resulted in a 2.39-log reduction. LTP of SO meat at 50°C for 12 minutes is an effective PHP for control of Vibrio species. BIOSECUR® F440D might contribute to the development of a value added PHP technique for reduction of Vv in oysters.
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Determination of Cane Berry Pomaces Benefits Through In Vitro Model for Human Colonic FermentationGoita, M'Famara 12 September 2013 (has links)
Cane berry pomaces have traditionally been considered waste products with little or no value. Yet these pomaces high levels of phenolic compounds such as anthocyanins, is a good source of dietary fiber. Because the pomaces are low in sugar and rich in fiber and dietary antioxidants, they have potential as food ingredients for the health food market. The pomace delivers health benefits associated with high fiber and the antioxidant polyphenolic compounds associated with whole fruits and juices without the high sugar content.
Some dietary fibers are substrates for anaerobic fermentation by the microbiome in the lower gastrointestinal (GI) tract. The anaerobic fermentation of dietary fiber results in a lowering of the pH in the biomass and production of short chain fatty acids. In this study, a model system mimicking colonic fermentation in the digestive tract was developed and used to assess fermentation of cane berry pomace by colonic bacteria. Pomace samples from blueberry and black raspberry, and Hi-Maize© resistant starch (a high amylose cornstarch used as the positive control) were treated with pepsin followed by pancreatin digestion to simulate the digestive changes in the upper gastrointestinal (GI) tract. After the digestion, the remaining undigested material was washed and air dried. The fiber was then fermented anaerobically with an inoculum of colonic bacteria prepared from fecal donations of healthy volunteers.
The fermentation of the blueberry and black raspberry pomaces using the inoculum from 5 individuals resulted in a wide range of SCFA production. Fermentation with Hi-maize© resistant starch resulted in production of higher concentrations of SCFAs compared to the cane berry pomace substrates. An inoculum, prepared by mixing individual stool samples from five individuals, provided a microbiota that represented a broader population, thus resulting in a more generalized result. The production of acetate, propionate and butyrate was significantly higher in the pooled sample compared to results from individual donors.
A different group of 5 individuals consumed a diet rich in resistant starch (RS) for a month and at the end of that period their stool samples were collected and used to prepare a pooled inoculum. The pooled inoculum from subjects with RS-fortified diet produced higher level of SCFAs than the pooled inoculum with non-fortified diet expect the Hi-Maize© RS which did not show difference at 0.05 significance level.
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Production of pyrethrins by tissue cultures of chrysanthemum cinerariaefoliumRajasekaran, T 01 1900 (has links)
Chrysanthemum cinerariaefolium
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Studies on the effect of plant foods on antioxidant enzyme system and their influnce on the chemically induced cytotoxicity in rats.AnilaKumar, K R 08 1900 (has links)
Influnce on the chemically induced cytotoxicity in rats.
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