Browsing by Subject "Phenolics"
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Item Anti-inflammatory Effect of Vigna Unguiculata Polyphenols in Raw 264.7 Macrophages(2013-04-29) Siska, Karla PThis study investigated the association between flavonoid profiles of different cowpea (Vigna Unguiculata) varieties with anti-inflammatory properties as a possible benefit against inflammatory bowel disease. Cowpea, a drought tolerant annual herbaceous legume that originated in Africa, is known to possess high levels of polyphenolics, which have demonstrated anti-inflammatory, immunoregulatory and antioxidant properties. Black, red, white, brown and light brown cowpeas were investigated for phenolic content and composition using UV-Visible Spectroscopy and HPLC; antioxidant activation mechanism (AOX) by oxygen radical absorbance capacity (ORAC). Anti-inflammatory activity was measured via NF-?B activation in Raw 264.7 macrophages challenged with a lipo-polysaccharide. Phenols, tannins and AOX activity were generally similar within phenotypes; however among light brown varieties, 09FCV-CC-27M, had among the highest phenols, tannins and AOX, whereas IAR-48 had among the lowest. White cowpea (EARLY ACRE) variety showed the least amount of total phenol content (78.2 mg GAE/g) and condensed tannin content (4.1 mg CE/g); whereas the red varieties (IT82D-889, IT97K-1042-3) contained the highest amounts of tannins (242 and 132 mg CE/g), and phenols (431 and 454 mg GAE/g) respectively. Antioxidant activity correlated with phenol content data. Anthocyanins were only found in the black cowpea. The red varieties had the highest levels of flavonols, which were mostly quercetin derivatives; the white and light brown (IAR-48) varieties had quercetin-3-O-diglucoside as the dominantcompound. The light brown variety (09FCV-CC-27M) had the highest amount of flavan-3-ols while in the white variety no flavan-3-ols were detected. Unexpectedly, the cowpea extracts with lower phenolic and tannins content, the white and light brown (IAR-48) varieties, showed significant (p<0.05) anti-inflammatory properties in the LPS induced macrophages, inhibiting the activation of NF-?B at different concentrations (0.33, 1.67 and 3.33 ?g extract/mL). Conversely, extracts with higher phenolic and tannin content did not induce anti-inflammatory response at similar concentrations, suggesting that tannins or other phenolics interfered with anti-inflammatory response at these concentrations. These results suggest that cowpea composition is an important determinant of anti-inflammatory response in inflammatory bowel disease.Item Chemical and Physical Properties of Breakfast Cereals and Snacks Made from Specialty Sorghums and Sorghum Bran Using Twin Screw Extruder(2012-02-14) Asif, MuhammadWhole ground white, high tannin and black sorghum with and without additional high tannin sorghum bran were used in different proportions to develop ready to eat breakfast cereals and snacks. The effect of extrusion on the phenolic compounds and on in vitro starch digestibility of sorghum based cereals and snacks were observed. Gluten free and gluten containing breakfast cereal and snacks were developed with different physical, chemical and sensory characteristic. By increasing the sorghum and bran level in the formulations, the bulk density of extrudates was increased while expansion ratio was decreased. Bowl life of extrudates was increased up to 18 min. when 60% whole ground white sorghum was used with additional 10% high tannin sorghum bran. Water soluble index was significantly higher for the extrudates without additional bran and decreased as bran was added. A positive correlation between water soluble index and expansion ratio (R^2=0.89) indicated that the more expansion ratio provided a large surface area for water to interact with starch and other soluble components. The retention of total phenols in these extrudates varied from 13-41% and it was found that extrudates with additional high tannin sorghum bran had more total phenols than extrudates without it. Sorghum extrudates showed a significant reduction in antioxidant activity varied from 21-83%. Similarly, the effect of extrusion on condensed tannins was detrimental, and their retention was ranged from 12-28%. The smaller particle size of ground sorghum increased the surface area of contact between composite flour components and extruder barrel which promoted interactions during extrusion, lowering condensed tannins and antioxidant activity. All sorghum based extrudates had significantly (P<0.05) lower starch digestibility than that of corn flour extrudates. All types of sorghum had non-significant difference in starch digestibility from 0.5-2hrs. After 16 hrs., high tannin sorghum extrudates had the lowest starch digestibility (79%), which was significantly different from other sorghum types. There was a negative correlation between the rapid digestible starch and tannin contents (R^2=0.62). Breakfast cereals made from different types of sorghum and bran levels were statistically equally rated in taste and overall acceptability.Item Development of management practices for artichoke production in southwest texas(2009-05-15) Shinohara, TogoThis research included studies for transplant and field crop management with thepurpose of optimizing stand establishment, crop performance and nutritional quality ofartichoke (Cynara scolymus L.) grown in southwest Texas.Post-transplanting heat (35/20oC vs. 25/10oC, day/night temperatures) or drought[30% Water holding capacity (WHC) vs. 60% WHC] stress alone or in combinationsignificantly reduced shoot or/and root growth of artichoke seedlings. Combined heatand drought stresses strongly affected shoot water status and root growth. Results fromthis study imply that it is desirable to improve stand establishment by either conditioningthe seedlings to improve root growth or by preventing leaf dehydration by these stresses.Therefore, effects of plant growth regulators (PGR) on root growth and shoot waterstatus were examined.Ethylene regulators, including precursors or a releasing compound [DLmethionine(MET), 1-aminocyclopropane-1-carboxylic acid (ACC) and ethephone(ETH)], and inhibitors [amino-ethoxyvinylglycine (AVG) and 1-methylcyclopropene (1-MCP)] were applied to seedlings to evaluate their effect on root growth and development. ACC and ETH (1-100 M?L-1) enhanced root hair, root area and lateralroots (only with ETH at 30 M?L-1).The effects of film-forming antitranspirants and abscisic acid (ABA, 500-2000mg?L-1) foliar application on physiological responses, water status and hardiness ofartichoke transplants were examined under drought stress. ABA at 1000 mg?L-1enhanced drought tolerance of transplants which was associated with the maintenance ofshoot water status via stomatal closure. Film-forming antitranspirants were not effectiveto mitigate drought stress. These results suggest that ACC and ETH as root enhancers,and ABA as a plant water conditioner, could be useful PGR?s to enhance standestablishment in artichoke seedlings.Field artichoke performance in response to irrigation [50, 75 and 100% cropevapotranspiration (ETc)] and N (0-180 kg?ha-1) rates were investigated during threeseasons at Texas A&M AgriLife Research in Uvalde, TX. Irrigation was more effectivethan N rates to optimize artichoke yield. Yield reduction by 50% ETc was associatedwith a decrease in head number and weight. The highest yield was obtained with 100%ETc and 120 kg?ha-1 N. This study also showed that deficit irrigation significantlyimproved artichoke head quality, such as phenolic content, but with significant yieldlosses.Item Post-harvest high heat treatment on grapes and the effects on wine quality relating compounds(2012-12) Zhang, Yanmei; Trela, Brent; Hellman, Edward W.; Mansouri, HosseinThis research evaluated simulated accumulated summer temperature conditions in grape shipping containers during transportation from vineyard to winery in Texas. Temperature treatments were applied to five batches of destemmed grapes comprised of three batches of red varieties and two batches of white varieties. After 0 to 15 hr treatments, the berries were processed and fermented to wines in micro scale. Phenolic constituents important to wine quality sensory perception, including total phenolics, anthocyanins, tannins and polymeric pigments, as well as color intensity, hue and standard wine parameters were quantified to evaluate the effects of heat at post-harvest stage on the subsequent wines. The results indicate that long distance transportation of berries in Texas may result in high phenolic extraction and elevated browning in white wines, while red wines tended to change red color intensity, tannin concentrations and red pigment profiles, which might not affect red wines sensorily. Heat treatment did not affect pH, titratable acidity, ethanol concentrations, browning, total phenolic concentrations or anthocyanin concentrations compared to the wines made from the low heat treated berries. The composition of phenolic constituents in red wines is relatively stable after the heat treatment before vinification.