Processing and Properties of a Phenolic Composite System

NASA Technical Reports Server (NTRS)

Hou, Tan-Hung; Bai, J. M.; Baughman, James M.

2006-01-01

Phenolic resin systems generate water as a reaction by-product via condensation reactions during curing at elevated temperatures. In the fabrication of fiber reinforced phenolic resin matrix composites, volatile management is crucial in producing void-free quality laminates. A commercial vacuum-bag moldable phenolic prepreg system was selected for this study. The traditional single-vacuum-bag (SVB) process was unable to manage the volatiles effectively, resulting in inferior voidy laminates. However, a double vacuum bag (DVB) process was shown to afford superior volatile management and consistently yielded void-free quality parts. The DVB process cure cycle (temperature /pressure profiles) for the selected composite system was designed, with the vacuum pressure application point carefully selected, to avoid excessive resin squeeze-outs and achieve the net shape and target resin content in the final consolidated laminate parts. Laminate consolidation quality was characterized by optical photomicrography for the cross sections and measurements of mechanical properties. A 40% increase in short beam shear strength, 30% greater flexural strength, 10% higher tensile and 18% higher compression strengths were obtained in composite laminates fabricated by the DVB process.

Carbon-Phenolic Cages for High-Speed Bearings. Part 1 - Friction and Wear Response of Phenolic Composite Impregnated with a Multiply-Alkylated Cyclopentane (MAC) Lubricant and MoS2 Solid Lubricant

DTIC Science & Technology

2003-01-01

AFRL/MLBT) was the program manager for the overall effort. The carbon -phenolic samples in the program were prepared by Mr. Wei Shih of Allcomp ... Inc ., City of Industry, CA. Mr. Shih also provided the mechanical and thermal property data for the carbon -phenolic specimens. Hitesh Trivedi and...of the program to characterize the material properties. Allcomp Inc ., City of Industry, California supplied all of the test specimens. The

Thermal Properties of Zeolite-Containing Composites

PubMed Central

Shimonosono, Taro; Hirata, Yoshihiro; Nishikawa, Kyohei; Sameshima, Soichiro; Sodeyama, Kenichi; Masunaga, Takuro; Yoshimura, Yukio

2018-01-01

A zeolite (mordenite)–pore–phenol resin composite and a zeolite–pore–shirasu glass composite were fabricated by hot-pressing. Their thermal conductivities were measured by a laser flash method to determine the thermal conductivity of the monolithic zeolite with the proposed mixing rule. The analysis using composites is useful for a zeolite powder with no sinterability to clarify its thermal properties. At a low porosity <20%, the thermal conductivity of the composite was in excellent agreement with the calculated value for the structure with phenol resin or shirasu glass continuous phase. At a higher porosity above 40%, the measured value approached the calculated value for the structure with pore continuous phase. The thermal conductivity of the monolithic mordenite was evaluated to be 3.63 W/mK and 1.70–2.07 W/mK at room temperature for the zeolite–pore–phenol resin composite and the zeolite–pore–shirasu glass composite, respectively. The analyzed thermal conductivities of monolithic mordenite showed a minimum value of 1.23 W/mK at 400 °C and increased to 2.51 W/mK at 800 °C. PMID:29534034

Effect of cluster thinning and prohexadione calcium applications on phenolic composition and sensory properties of red wines.

PubMed

Avizcuri-Inac, José-Miguel; Gonzalo-Diago, Ana; Sanz-Asensio, Jesús; Martínez-Soria, María-Teresa; López-Alonso, Miguel; Dizy-Soto, Marta; Echávarri-Granado, José-Federico; Vaquero-Fernández, Luis; Fernández-Zurbano, Purificación

2013-02-06

The overall objective of this study was to investigate the effect of manual cluster thinning (CT) and the application of the growth regulator Prohexadione calcium (ProCa) on the phenolic composition and the sensory profile of Tempranillo and Grenache wines produced from treated vines in La Rioja (Spain). ProCa was applied at preblooming and CT was carried out at veraison in two consecutive years. Different physicochemical parameters and analyses of phenolic compounds were carried out in control, CT and ProCa grapes and wines and wine sensory was performed. Thinning treatments decreased crop yield, besides ProCa application reduced berry size, and berry weight. Color and phenolic composition of Grenache and Tempranillo wines in general were affected by thinning treatments, with an increase in anthocyanin, flavanol and flavonol concentrations. In sensory analysis, wines obtained from thinned vines presented higher values for several aromatic (e.g., white and yellow fruits, fresh flowers) and taste attributes (i.e., astringency, bitternes, persistence). CT and ProCa treatments resulted in an improvement in wine quality. In general, similar results in phenolic composition, sensory properties and quality of wines were obtained by manual and chemical cluster thinning. ProCa as a growth regulator may be an option for a quality vitiviniculture.

Vapor Grown Carbon Fiber/Phenolic Matrix Composites for Rocket Nozzles and Heat Shields

NASA Technical Reports Server (NTRS)

Patton, R. D.; Pittman, C. U., Jr.; Wang, L.; Day, A.; Hill, J. R.

2001-01-01

The ablation and mechanical and thermal properties of vapor grown carbon fiber (VGCF)/phenolic resin composites were evaluated to determine the potential of using this material in solid rocket motor nozzles. Composite specimens with varying VGCF loading (30%-50% wt) including one sample with ex-rayon carbon fiber plies were prepared and exposed to a plasma torch for 20 s with a heat flux of 16.5 MW/sq m at approximately 1650 C. Low erosion rates and little char formation were observed, confirming that these materials were promising for rocket motor nozzle materials. When fiber loadings increased, mechanical properties and ablative properties improved. The VGCF composites had low thermal conductivities (approximately 0.56 W/m-C) indicating they were good insulating materials. If a 65% fiber loading in VGCF composite can be achieved, then ablative properties are projected to be comparable to or better than the composite material currently used on the Space Shuttle Reusable Solid Rocket Motor (RSRM).

Properties and processing characteristics of low density carbon cloth phenolic composites

NASA Technical Reports Server (NTRS)

Wang, C. Jeff

1993-01-01

Ply-lift and pocketing are two critical anomalies of carbon cloth phenolic composites (CCPC) in rocket nozzle applications. Ply lift occurs at low temperatures when the A/P and in-plane permeabilities of the composite materials are still very low and in-plane porous paths are blocked. Pocketing occurs at elevated temperatures when in-plane permeability is reduced by the A/P compressive stress. The thermostructural response of CCPC in a rapid heating environment involves simultaneous heat, mass, and momentum transfer along with the degradation of phenolic resin in a multiphase system with temperature- and time-dependent material properties as well as dynamic processing conditions. Three temperature regions represent the consequent chemical reactions, material transformations, and property transitions, and provide a quick qualitative method for characterizing the thermostructural behavior of a CCPC. In order to optimize the FM5939 LDCCP (low density carbon cloth phenolic) for the nozzle performance required in the Advanced Solid Rocket Motor (ASRM) program, a fundamental study on LDCCP materials was conducted. The cured composite has a density of 1.0 +/- 0.5 gm/cc which includes 10 to 25 percent void volume. The weight percent of carbon microballoon is low (7-15 percent). However, they account for approximately one third of the volume and historically their percentages have not been controlled very tightly. In addition, the composite properties show no correlation with microballoon weight percent or fiber properties (e.g. fiber density or fiber moisture adsorption capacity). Test results concerning the ply-lift anomaly in the MNASA motor firings were: (1) Steeper ply angle (shorter path lenght) designs minimized/eliminated by lifting, (2) material with higher void volume ply lifted less frequently, (3) materials with high (greater than 9 percent) microballoon content had a higher rate of ply lifting, and (4) LDCCP materials failed at microballoon-resin interfaces. The objectives of this project are: (1) to investigate the effects of carbon microballoon and cabosil fillers as well as fiber heat treatment on plylift-related mechanical properties, (2) to develop a science-based thermostructural process model for the carbon phenolics. The model can be used in the future for the selection of the improved ASRM materials, (3) to develop the micro-failure mechanisms for the ply-lift initiation and propagation processes during the thermoelastic region of phenolic degradation, i.e. postcuring and devolatilization.

Acidolysis small molecular phenolic ether used as accelerator in photosensitive diazonaphthaquinone systems

NASA Astrophysics Data System (ADS)

Zhou, Haihua; Zou, Yingquan

2006-03-01

The photosensitive compounds in the photosensitive coatings of positive PS plates are the diazonaphthaquinone derivatives. Some acidolysis small molecular phenolic ethers, which were synthesized by some special polyhydroxyl phenols with vinyl ethyl ether, are added in the positive diazonaphthaquinone photosensitive composition to improve its sensitivity, composed with photo-acid-generators. The effects to the photosensitivity, anti-alkali property, anti-isopropyl alcohol property, dot resolution and line resolution of the coatings are studied with different additive percent of the special phenolic ethers. In the conventional photosensitive diazonaphthaquinone systems for positive PS plates, the photosensitivity is improved without negative effects to resolution, anti-alkali and anti-isopropyl alcohol properties when added about 5% of the special acidolysis phenolic ethers, EAAE or DPHE, composed with photo-acid-generators.

Chemical composition and antibacterial activities of lupin seeds extracts.

PubMed

Lampart-Szczapa, Eleonora; Siger, Aleksander; Trojanowska, Krystyna; Nogala-Kalucka, Małgorzata; Malecka, Maria; Pacholek, Bogdan

2003-10-01

Determination of influence of lupin natural phenolic compounds on antibacterial properties of its seeds was carried out. Raw material were seeds of Lupinus albus, L. luteus, and L. angustifolius. The methods included the determination of the content of proteins, total phenolic compounds, free phenolic acids, and tannins as well as antibacterial properties with ethanol extracts. The content of total phenolic compounds was smaller in testas than in cotyledons and the highest levels are observed in bitter cultivars of Lupinus albus cv. Bac and L. angustifolius cv. Mirela. Lupin tannins mainly occurred in cotyledons of the white lupin, predominantly in the bitter cultivar Bac. Free phenolic acids were mainly found in testas. Only extracts from the testas displayed antibacterial properties, which excludes the possibility of alkaloid influence on the results. The results suggest that inhibition of test bacteria growth depended mainly upon the content of the total phenolic compounds.

A Comparison between Characterization and Biological Properties of Brazilian Fresh and Aged Propolis

PubMed Central

Schmidt, Eduardo Morgado; Stock, Daniele; Chada, Fabio José Garcia; Finger, Daiane; Christine Helena Frankland Sawaya, Alexandra; Eberlin, Marcos Nogueira; Felsner, Maria Lurdes; Quináia, Sueli Pércio; Torres, Yohandra Reyes

2014-01-01

Objective. As propolis is a highly valued bee product, we aimed to verify the quality of aged propolis, investigating their phenolic and flavonoid composition, levels of toxic metals, radical scavenging and antimicrobial activities. Material and Methods. Samples of fresh and aged propolis of six different beekeepers, from the same geographical location, were investigated in terms of their phenolic and flavonoid composition and levels of Pb, Cd, and Cr, as well as radical scavenging and antimicrobial activities. Results. The two groups of propolis had similar qualitative composition by HPLC-PDA and ESI(-)-MS. Fresh propolis and aged propolis show no differences when average values of extraction yield, flavonoids, EC50, or MIC were compared and both types of propolis showed good antimicrobial activity at low concentrations. Only levels of phenolic compounds were higher in fresh propolis. Conclusion. The propolis samples considered in this study, aged or fresh, had similar qualitative composition, although they were collected in different periods. Samples only differed in their levels of total phenolic content. Moreover, aged propolis conserves significant radical scavenging and antimicrobial properties. We suggest that aged propolis should not be discarded but explored for alternative applications. PMID:25530958

HPLC-UV-ESI-MS analysis of phenolic compounds and antioxidant properties of Hypericum undulatum shoot cultures and wild-growing plants.

PubMed

Rainha, Nuno; Koci, Kamila; Coelho, Ana Varela; Lima, Elisabete; Baptista, José; Fernandes-Ferreira, Manuel

2013-02-01

LC-UV and LC-MS analysis were used to study the phenolic composition of water extracts of Hypericum undulatum (HU) shoot cultures and wild-growing (WG) plants. Total phenolic content (TPC), determined using the Folin-Ciocalteu assay, and the antioxidant activity measured by two complementary methods were also performed for each sample. Mass spectrometry revealed several phenolics acids with quinic acid moieties, flavonols, mostly quercetin, luteolin and apigenin glycosides, flavan-3-ols (catechin and epicatechin) and the xanthonoid mangiferin. Differences in phenolic composition profile and TPC were found between the samples. The major phenolic in HU culture-growing (CG) samples is chlorogenic acid, followed by epicatechin, quercitrin and isoquercitrin. The WG plants presents hyperoside as the main phenolic, followed by isoquercitrin, chlorogenic acid and quercetin. The TPC and antioxidant activity were higher in samples from WG plants. Copyright © 2012 Elsevier Ltd. All rights reserved.

Thermal Properties of Capparis Decidua (ker) Fiber Reinforced Phenol Formaldehyde Composites

DOE Office of Scientific and Technical Information (OSTI.GOV)

Singh, G. P.; Mangal, Ravindra; Bhojak, N.

2010-06-29

Simultaneous measurement of effective thermal conductivity ({lambda}), effective thermal diffusivity ({kappa}) and specific heat of Ker fiber reinforced phenol formaldehyde composites have been studied by transient plane source (TPS) technique. The samples of different weight percentage typically (5, 10, 15, 20 and 25%) have been taken. It is found that values of effective thermal conductivity and effective thermal diffusivity of the composites decrease, as compared to pure phenol formaldehyde, as the fraction of fiber loading increases. Experimental data is fitted on Y. Agari model. Values of thermal conductivity of composites are calculated with two models (Rayleigh, Maxwell and Meredith-Tobias model).more » Good agreement between theoretical and experimental result has been found.« less

Physical and mechanical properties of bio-composites from wood particles and liquefied wood resin

Treesearch

Hui Pan; Todd F. Shupe; Chung-Yun Hse

2009-01-01

Compression molded composites were made from wood particles and a liquefied wood/phenol/formaldehyde co-condensed resin. Based on our previous research, a phenol to wood (P/W) ratio of 2/1 was chosen for this study. The two experimental variables selected were: 1) liquefaction temperature (150o and 180oC) and 2) cooking method (atmospheric and sealed). Panels were...

Examining the Relationship Between Ballistic and Structural Properties of Lightweight Thermoplastic Unidirectional Composite Laminates

DTIC Science & Technology

2011-08-01

Kevlar KM2® Style 705 PVB phenolic woven aramid composite was included. A developmental unidirectional thermoplastic aramid fiber, Honeywell...Examining the Relationship Between Ballistic and Structural Properties of Lightweight Thermoplastic Unidirectional Composite Laminates by...Unidirectional Composite Laminates Lionel R. Vargas-Gonzalez, Shawn M. Walsh, and James C. Gurganus Weapons and Materials Research Directorate, ARL

Characterization and immobilization of Trametes versicolor laccase on magnetic chitosan-clay composite beads for phenol removal.

PubMed

Aydemir, Tülin; Güler, Semra

2015-01-01

Laccase from Trametes versicolor was immobilized on magnetic chitosan-clay composite beads by glutaraldehyde crosslinking. The physical, chemical, and biochemical properties of the immobilized laccase and its application in phenol removal were comprehensively investigated. The structure and morphology of the composite beads were characterized by SEM, TGA, and FTIR analyses. The immobilized laccase showed better storage stability and higher tolerance to the changes in pH and temperature compared with free laccase. Moreover, the immobilized laccase retained more than 75% of its original activity after 10 cycles. The efficiency of phenol removal by immobilized laccase was about 80% under the optimum conditions after 4 h.

Synthesis of improved phenolic resins

NASA Technical Reports Server (NTRS)

Delano, C. B.; Mcleod, A. H.

1979-01-01

Twenty seven addition cured phenolic resin compositions were prepared and tested for their ability to give char residues comparable to state-of-the-art phenolic resins. Cyanate, epoxy, allyl, acrylate, methacrylate and ethynyl derivatized phenolic oligomers were investigated. The novolac-cyanate and propargyl-novolac resins provided anaerobic char yields at 800 C of 58 percent. A 59 percent char yield was obtained from modified epoxy novolacs. A phosphonitrilic derivative was found to be effective as an additive for increasing char yields. The novolac-cyanate, epoxy-novolac and methacrylate-epoxy-novolac systems were investigated as composite matrices with Thornel 300 graphite fiber. All three resins showed good potential as composite matrices. The free radical cured methacrylate-epoxy-novolac graphite composite provided short beam shear strengths at room temperature of 93.3 MPa (13.5 ksi). The novolac-cyanate graphite composite produced a short beam shear strength of 74 MPa (10.7 ksi) and flexural strength of 1302 MPa (189 ksi) at 177 C. Air heat aging of the novolac-cyanate and epoxy novolac based composites for 12 weeks at 204 C showed good property retention.

Tensile and burning properties of clay/phenolic/GF composite and its application

NASA Astrophysics Data System (ADS)

Diharjo, Kuncoro; Armunanto, V. Bram; Kristiawan, S. Adi

2016-03-01

Composite material has been widely used in automotive due to its properties can be improved by combining with reinforcement, like fiber and particle to enhance mechanical properties and burning resistance. This study aims to investigate the tensile and burning properties of hybrid composite combining glass fiber and clay in phenolic resin. The clay was produced from roof tile rejected by tile industries in Sokka, Kebumen, Indonesia. The composite was made using a press mold method for different number of laminates and orientation of woven-roving-glass-fiber/ WRGF (0/90 and ±45), and the total volume fraction of fiber and clay is constant 40%. The specimens were tested using universal testing machine for tensile properties and burning tests apparatus for burning resistance (time to ignite/ TTI and burning rate/ BR). The enhancing of the Clay/Penolic/GF composite can be performed by the increasing of GF laminates, and the composite with 0/90 orientation of WRGF has higher tensile strength and modulus compared to that with ±45 orientation of WRGF. Both composite with 0/90 and ±45 orientation of WRGF have similar burning resistance (TTI and BR) and the composite containing 13 laminates of WR-GF shows the best burning resistance. According to these properties, this composite has good opportunity to be applied as car body panels or other structure in industries due to save weight and high burning resistance.

Changes in antioxidant activity and phenolic acid composition of tarhana with steel-cut oats.

PubMed

Kilci, A; Gocmen, D

2014-02-15

Steel-cut oats (SCO) was used to replace wheat flour in the tarhana formulation (control) at the levels of 10%, 20%, 30% and 40% (w/w). Control sample included no SCO. Substitution of wheat flour in tarhana formulation with SCO affected the mineral contents positively. SCO additions also increased phenolic acid contents of tarhana samples. The most abundant phenolic acids were ferulic and vanillic acids, followed by syringic acid in the samples with SCO. Tarhana samples with SCO also showed higher antioxidant activities than the control. Compared with the control, the total phenolic content increased when the level of SCO addition was increased. SCO addition did not have a deteriorative effect on sensory properties of tarhana samples and resulted in acceptable soup properties in terms of overall acceptability. SCO addition improved the nutritional and functional properties of tarhana by causing increases in antioxidant activity, phenolic content and phenolic acids. Copyright © 2013 Elsevier Ltd. All rights reserved.

Chemical composition and physicochemical properties of green banana (Musa acuminata x balbisiana Colla cv. Awak) flour.

PubMed

Haslinda, W H; Cheng, L H; Chong, L C; Noor Aziah, A A

2009-01-01

Flour was prepared from peeled and unpeeled banana Awak ABB. Samples prepared were subjected to analysis for determination of chemical composition, mineral, dietary fibre, starch and total phenolics content, antioxidant activity and pasting properties. In general, flour prepared from unpeeled banana was found to show enhanced nutrition values with higher contents of mineral, dietary fibre and total phenolics. Hence, flour fortified with peel showed relatively higher antioxidant activity. On the other hand, better pasting properties were shown when banana flour was blended with peel. It was found that a relatively lower pasting temperature, peak viscosity, breakdown, final viscosity and setback were evident in a sample blended with peel.

Phenolic characterisation of red wines from different grape varieties cultivated in Mendoza province (Argentina).

PubMed

Fanzone, Martín; Zamora, Fernando; Jofré, Viviana; Assof, Mariela; Gómez-Cordovés, Carmen; Peña-Neira, Álvaro

2012-02-01

Knowledge of the chemical composition of wine and its association with the grape variety/cultivar is of paramount importance in oenology and a necessary tool for marketing. Phenolic compounds are very important quality parameters of wines because of their impact on colour, taste and health properties. The aim of the present work was to study and describe the non-flavonoid and flavonoid composition of wines from the principal red grape varieties cultivated in Mendoza (Argentina). Sixty phenolic compounds, including phenolic acids/derivatives, stilbenes, anthocyanins, flavanols, flavonols and dihydroflavonols, were identified and quantified using high-performance liquid chromatography with diode array detection coupled with electrospray ionisation mass spectrometry (HPLC-DAD/ESI-MS). Marked quantitative differences could be seen in the phenolic profile among varieties, especially in stilbenes, acylated anthocyanins and other flavonoids. The polyphenolic content of Malbec wines was higher compared with the other red varieties. Dihydroflavonols represent a significant finding from the chemotaxonomic point of view, especially for Malbec variety. This is the first report on the individual phenolic composition of red wines from Mendoza (Argentina) and suggests that anthocyanins, flavanols and phenolic acids exert a great influence on cultivar-based differentiation. Copyright © 2011 Society of Chemical Industry.

Phenolic content and antioxidant properties of seeds from different grape cultivars grown in Iran.

PubMed

Mirbagheri, Vasigheh Sadat; Alizadeh, Ebrahim; Yousef Elahi, Mostafa; Esmaeilzadeh Bahabadi, Sedigheh

2018-02-01

This study investigated the antioxidant activity and phenolic composition of seed extracts from three grape cultivars grown in Iran. Folin Ciocalteu method was used for the determination of the total phenolic contents and GC-MS was used for the analysis of phenolic compositions. 1,1-diphenyl-2-picrylhydrazyl (DPPH) method was used to evaluate the antioxidant activity. The highest and the lowest total phenolic contents of seed extract were found in the black and green grape, respectively. The content of individual phenols such as Frulic acid, Gentistic acid, Syringic acid, (+) Catechin, Chlorogenic acid and (-)- Epicatchin gallate was cultivars dependent. The antioxidant activity of the seed extracts ranged from 34.03% (Green) to 53.63% (Black). Generally, the Black grape seed extract with the total phenolic content (3 ± 0.01 mg tannic acid/g DM), DPPH (53.63 ± 0.34%), IC 50 and AEAC (7.41 and 16.92 mg/mL) showed the highest level of total antioxidant capacity.

Reactive Diazonium-Modified Silica Fillers for High-Performance Polymers.

PubMed

Sandomierski, Mariusz; Strzemiecka, Beata; Chehimi, Mohamed M; Voelkel, Adam

2016-11-08

We describe a simple way of modification of three silica-based fillers with in situ generated 4-hydroxymethylbenzenediazonium salt ( + N 2 -C 6 H 4 -CH 2 OH). The rationale for using a hydroxyl-functionalized diazonium salt is that it provides surface-functionalized fillers that can react with phenolic resins. The modification of silica by diazonium salts was assessed using Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS). FTIR spectroscopy permitted the tracking of benzene ring breathing and C-C. The absence of the characteristic N≡N stretching vibration in the 2200-2300 cm -1 range indicates the loss of the diazonium group. XPS results indicate a higher C/Si atomic ratio after the diazonium modification of fillers and the presence of π-π* C1s satellite peaks characteristic of the surface-tethered aromatic species. Adhesion of aryl layers to the silicas is excellent because they withstand harsh thermal and organic solvent treatments. Phenolic resins (used, for example, as binders in abrasive products) were filled with diazonium-modified silicas at 10-25 wt %. The reactivity of the fillers toward phenolic resins was evaluated by the determination of the flow distance. After annealing at 180 °C, the diazonium-modified silica/phenolic resin composites were mechanically tested using the three-point flexural method. The flexural strength was found to be up to 35% higher than that of the composites prepared without any diazonium salts. Diazonium-modified silica with surface-bound -CH 2 -OH groups is thus ideal reactive filler for phenolic resins. Such filler ensures interfacial chemical reactions with the matrix and imparts robust mechanical properties to the final composites. This specialty diazonium-modified silica will find potential application as fillers in the composites for the abrasive industry. More generally, aryl diazonium salts are a unique new series of compounds for tailoring the surface properties of fillers and tuning the physicochemical and mechanical properties of polymer composites.

Chemical composition and sensory properties of non-wooded and wooded Shiraz (Vitis vinifera L.) wine as affected by vineyard row orientation and grape ripeness level.

PubMed

Hunter, Jacobus J; Volschenk, Cornelis G

2018-05-01

The study aimed to unravel vineyard row orientation (NS, EW, NE-SW, NW-SE) and grape ripeness level (23, 25, 27 °Balling) implications for grape and wine composition and sensory properties/style (non-wooded/wooded wines) of Vitis vinifera L. cv. Shiraz (rootstock 101-14 Mgt). Soluble solid/titratable acidity ratios were lowest for EW, whereas warmer canopy sides (NW, N, NE) advanced grape ripening. Skin anthocyanins and phenolics generally decreased with ripening. NW-SE rows and S, SE, E and NE canopy sides showed highest skin total anthocyanins and phenolics. Wine total anthocyanins and phenolics increased with grape ripening; EW had lower values. Wine phenolic contents differed between canopy sides; N, NE, E and SE tended higher. Wine sensory profiles increased with grape ripening. For non-wooded wines, NW-SE and NE-SW row orientations generally resulted in highest scores, followed by NS. For EW rows, the N side presented better wines. Wood addition enhanced specific sensory descriptor perceptions. A large collection of wine styles surfaced in the same vineyard and terroir, increasing options to contribute positively to sustainable products. The study generated globally applicable, novel information vital for unlocking and valorising terroir/site potential for grape and wine chemical composition and wine sensory/style properties. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Fiber reinforced hybrid phenolic foam

NASA Astrophysics Data System (ADS)

Desai, Amit

Hybrid composites in recent times have been developed by using more than one type of fiber reinforcement to bestow synergistic properties of the chosen filler and matrix and also facilitating the design of materials with specific properties matched to end use. However, the studies for hybrid foams have been very limited because of problems related to fiber dispersion in matrix, non uniform mixing due to presence of more than one filler and partially cured foams. An effective approach to synthesize hybrid phenolic foam has been proposed and investigated here. Hybrid composite phenolic foams were reinforced with chopped glass and aramid fibers in varied proportions. On assessing mechanical properties in compression and shear several interesting facts surfaced but overall hybrid phenolic foams exhibited a more graceful failure, greater resistance to cracking and were significantly stiffer and stronger than foams with only glass and aramid fibers. The optimum fiber ratio for the reinforced hybrid phenolic foam system was found to be 1:1 ratio of glass to aramid fibers. Also, the properties of hybrid foam were found to deviate from rule of mixture (ROM) and thus the existing theories of fiber reinforcement fell short in explaining their complex behavior. In an attempt to describe and predict mechanical behavior of hybrid foams a statistical design tool using analysis of variance technique was employed. The utilization of a statistical model for predicting foam properties was found to be an appropriate tool that affords a global perspective of the influence of process variables such as fiber weight fraction, fiber length etc. on foam properties (elastic modulus and strength). Similar approach could be extended to study other fiber composite foam systems such as polyurethane, epoxy etc. and doing so will reduce the number of experimental iterations needed to optimize foam properties and identify critical process variables. Diffusivity, accelerated aging and flammability of hybrid foams were evaluated and the results indicate that hybrid foam surpassed several commercial foams and thus could fulfill the current needs for an insulation material which is low cost, has excellent fire properties and retains compressive stiffness even after aging.

Degradation behavior of carbon nanotubes/phenol-furfuryl alcohol multifunctional composites with aerospace application

NASA Astrophysics Data System (ADS)

Conejo, L. S.; Costa, M. L.; Oishi, S. S.; Botelho, E. C.

2017-10-01

Lightweight and highly conductive composite associated with good impact and tribological properties could be used in the aerospace industry to replace metal for an aircraft skin and still provide effective shielding against electromagnetic interference (EMI). Also, phenol-furfuryl alcohol resins (PFA) are excellent candidates to replace existing thermoset matrices used for obtaining glassy carbon, both in its pure form and reinforced with nanoscale structures. The synthesis of PFA allow obtaining a resin with better properties than that showed by conventional phenolic resins and with synthesis and cure processes more controlled than observed for the furfuryl alcohol resin. This work has as main purpose the synthesis and thermal characterization of PFA resin and its nanostructured composites with different concentrations of carbon nanotubes (0, 0.1, 0.5 and 1.0 wt%). PFA resin was synthesized with 1:2:1 molar ratio of phenol/formaldehyde/furfuryl alcohol, according to the more appropriate condition obtained previously. The specimens were evaluated by thermogravimetry (TGA) to knowledge of the temperature of thermal degradation, either by actual analyses as simulated by simulation heating rate conversion software (known as Highway Simulation). The introduction of CNT in PFA sample does not affect its thermal stability. The values of residual weight found for samples with CNT additions are close to the values of the phenolic resin in the literature (about 60% residual weight).

Phytochemical profile of main antioxidants in different fractions of purple and blue wheat, and black barley.

PubMed

Siebenhandl, Susanne; Grausgruber, Heinrich; Pellegrini, Nicoletta; Del Rio, Daniele; Fogliano, Vincenzo; Pernice, Rita; Berghofer, Emmerich

2007-10-17

Two pigmented wheat genotypes (blue and purple) and two black barley genotypes were fractionated in bran and flour fractions, examined, and compared for their free radical scavenging properties against 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt radical cation (Trolox equivalent antioxidant capacity, TEAC), ferric reducing antioxidant power (FRAP), total phenolic content (TPC), phenolic acid composition, carotenoid composition, and total anthocyanin content. The results showed that fractionation has a significant influence on the antioxidant properties, TPC, anthocyanin and carotenoid contents, and phenolic acid composition. Bran fractions had the greatest antioxidant activities (1.9-2.3 mmol TEAC/100 g) in all four grain genotypes and were 3-5-fold higher than the respective flour fractions (0.4-0.7 mmol TEAC/100 g). Ferulic acid was the predominant phenolic acid in wheat genotypes (bran fractions) while p-coumaric acid was the predominant phenolic acid in the bran fractions of barley genotypes. High-performance liquid chromatography analysis detected the presence of lutein and zeaxanthin in all fractions with different distribution patterns within the genotypes. The highest contents of anthocyanins were found in the middlings of black barley genotypes or in the shorts of blue and purple wheat. These data suggest the possibility to improve the antioxidant release from cereal-based food through selection of postharvest treatments.

Plant Phenols as Antibiotic Boosters: In Vitro Interaction of Olive Leaf Phenols with Ampicillin.

PubMed

Lim, Anxy; Subhan, Nusrat; Jazayeri, Jalal A; John, George; Vanniasinkam, Thiru; Obied, Hassan K

2016-03-01

The antimicrobial properties of olive leaf extract (OLE) have been well recognized in the Mediterranean traditional medicine. Few studies have investigated the antimicrobial properties of OLE. In this preliminary study, commercial OLE and its major phenolic secondary metabolites were evaluated in vitro for their antimicrobial activities against Escherichia coli and Staphylococcus aureus, both individually and in combination with ampicillin. Besides luteolin 7-O-glucoside, OLE and its major phenolic secondary metabolites were effective against both bacteria, with more activity on S. aureus. In combination with ampicillin, OLE, caffeic acid, verbascoside and oleuropein showed additive effects. Synergistic interaction was observed between ampicillin and hydroxytyrosol. The phenolic composition of OLE and the stability of olive phenols in assay medium were also investigated. While OLE and its phenolic secondary metabolites may not be potent enough as stand-alone antimicrobials, their abilities to boost the activity of co-administered antibiotics constitute an imperative future research area. Copyright © 2016 John Wiley & Sons, Ltd.

Sensory representation of typicality of Cabernet franc wines related to phenolic composition: impact of ripening stage and maceration time.

PubMed

Cadot, Yves; Caillé, Soline; Samson, Alain; Barbeau, Gérard; Cheynier, Véronique

2012-06-30

Phenolics are responsible for important sensory properties of red wines, including colour, astringency, and possibly bitterness. From a technical viewpoint, the harvest date and the maceration duration are critical decisions for producing red wine with a distinctive style. But little is known about the evolution of phenolics and of their extractability during ripening to predict the composition of the wine and related sensory properties. The aim of this study was to understand the relationship between the sensory profile of the wines and (i) the ripening stage of the berries (harvest date) and (ii) the extraction time (maceration duration). Phenolic acids, flavonols, anthocyanins and proanthocyanidins of Vitis Vinifera var. Cabernet franc were measured in grapes and in wines from two stages of maturity and with two maceration durations. Phenolic composition was analysed by high performance liquid chromatography, after fractionation and thiolysis for proanthocyanidins. The distinctive style of wines was investigated by descriptive analysis (trained panel), Just About Right profiles and typicality assessment (wine expert panel). Relationships between phenolics and sensory attributes were established by multidimensional analysis, and phenolics were classified according to sensory data by ANOVA and PLS regressions. Astringency, bitterness, colour intensity and alcohol significantly increased with ripening and astringency and colour intensity increased with maceration time. Grape anthocyanins increased and thiolysis yield significantly decreased with ripening. In wine, proanthocyanidins increased, and mean degree of polymerisation and thiolysis yield decreased with longer extraction time. The high impact of harvest date on the sensory profiles could be due to changes in anthocyanin and sugar contents, but also to an evolution of proanthocyanidins. Moreover, proanthocyanidin composition was affected by maceration time as suggested by the decrease of thiolysis yield. Our results suggest that the wine sensory quality established by the expert panel, is linked as expected to grape quality at harvest, reflected by sugar and anthocyanin contents, but also by thiolysis yield, which requires elucidation. Copyright © 2012 Elsevier B.V. All rights reserved.

Computer-Aided Process Model For Carbon/Phenolic Materials

NASA Technical Reports Server (NTRS)

Letson, Mischell A.; Bunker, Robert C.

1996-01-01

Computer program implements thermochemical model of processing of carbon-fiber/phenolic-matrix composite materials into molded parts of various sizes and shapes. Directed toward improving fabrication of rocket-engine-nozzle parts, also used to optimize fabrication of other structural components, and material-property parameters changed to apply to other materials. Reduces costs by reducing amount of laboratory trial and error needed to optimize curing processes and to predict properties of cured parts.

Phenolic compositions and antioxidant attributes of leaves and stems from three inbred varieties of Lycium chinense Miller harvested at various times.

PubMed

Liu, Shih-Chuan; Lin, Jau-Tien; Hu, Chao-Chin; Shen, Bo-Yan; Chen, Ting-Yo; Chang, Ya-Ling; Shih, Chia-Huing; Yang, Deng-Jye

2017-01-15

Antioxidant components and properties (assayed by scavenging DPPH radicals, TEAC, reducing power, and inhibiting Cu(2+)-induced human LDL oxidation) of leaves and stems from three inbred varieties of Lycium chinense Miller, namely ML01, ML02 and ML02-TY, harvested from January to April were studied. Their flavonoid and phenolic acid compositions were also analyzed by HPLC. For each variety, the leaves and stems collected in higher temperature month had higher contents of total phenol, total flavonoid and condensed tannin. Contents of these components in the samples collected in different months were in the order: April (22.3°C)>March (18.0°C)>January (15.6°C)>February (15.4°C). Antioxidant activities of the leaves and stems for all assays also showed similar trends. The samples from different varieties collected in the same month also possessed different phenolic compositions and contents and antioxidant activities. Their antioxidant activities were significantly correlated with flavonoid and phenolic contents. Copyright © 2016. Published by Elsevier Ltd.

Effect of fabricated density and bamboo species on physical-mechanical properties of bamboo fiber bundle reinforced composites

Treesearch

Jiulong Xie; Jinqiu Qi; Tingxing Hu; Cornelis F. De Hoop; Chung Yun Hse; Todd F. Shupe

2016-01-01

Bamboo stems were subjected to a mechanical treatment process for the extraction of bamboo fiber bundles. The fiber bundles were used as reinforcement for the fabrication of high-performance composites with phenolic resins as matrix. The influence of fabricated density and bamboo species on physical–mechanical properties of bamboo fiber bundle reinforced composites (...

Effects of deep-fat frying temperature on antioxidant properties of whole wheat doughnuts

USDA-ARS?s Scientific Manuscript database

The total phenolic content (TPC), phenolic acid composition, and in vitro antioxidant capacity of whole wheat donuts fried at 120, 140, 160, or 180'C were determined and compared in two types of wheat to identify the effects of frying temperature. Significant differences (P<0.05) in TPC were observe...

Synthesis of improved phenolic and polyester resins

NASA Technical Reports Server (NTRS)

Delano, C. B.

1980-01-01

Thirty-seven cured phenolic resin compositions were prepared and tested for their ability to provide improved char residues and moisture resistance over state of the art epoxy resin composite matrices. Cyanate, epoxy novolac and vinyl ester resins were investigated. Char promoter additives were found to increase the anaerobic char yield at 800 C of epoxy novolacs and vinyl esters. Moisture resistant cyanate and vinyl ester compositions were investigated as composite matrices with Thornel 300 graphite fiber. A cyanate composite matrix provided state of the art composite mechanical properties before and after humidity exposure and an anaerobic char yield of 46 percent at 800 C. The outstanding moisture resistance of the matrix was not completely realized in the composite. Vinyl ester resins showed promise as candidates for improved composite matrix systems.

Effect of latitude and altitude on the terpenoid and soluble phenolic composition of juniper (Juniperus communis) needles and evaluation of their antibacterial activity in the boreal zone.

PubMed

Martz, Françoise; Peltola, Rainer; Fontanay, Stéphane; Duval, Raphaël E; Julkunen-Tiitto, Riitta; Stark, Sari

2009-10-28

The demand for dry juniper (Juniperus communis) needles as a raw material for the food, pharmaceutical, and cosmetic industries has increased rapidly in recent years. Juniper needles are known to be rich in terpenoids and phenolics, but their chemical composition and antibacterial properties have not been well-characterized. In this study, we describe the soluble phenolic and terpenoid composition of juniper needles collected in Finland (n = 125) and demonstrate that the concentration of these compounds clearly increased with latitude and altitude with, however, a stronger latitudinal effect (a higher content of monoterpenoids, proanthocyanidins, and flavonols in northern latitudes). Analysis of methanolic extracts showed quite good activity against both antibiotic-sensitive and -resistant Staphylococcus aureus strains and suggested an important role of the soluble phenolic fraction. Finally, we demonstrate the relative lack of toxicity of juniper extracts on keratinocytes and fibroblastic cells, raising the possibility of their use in preventing bacterial skin infection.

Cooking quality properties and free and bound phenolics content of brown, black, and red rice grains stored at different temperatures for six months.

PubMed

Ziegler, Valmor; Ferreira, Cristiano Dietrich; Hoffmann, Jessica Fernanda; Chaves, Fábio Clasen; Vanier, Nathan Levien; de Oliveira, Maurício; Elias, Moacir Cardoso

2018-03-01

The changes in cooking quality and phenolic composition of whole black and red rice grains stored during six months at different temperatures were evaluated. Brown rice with known cooking quality properties and low phenolic levels was used for purposes comparison. All rice genotypes were stored at 13% moisture content at temperatures of 16, 24, 32, and 40°C. Cooking time, hardness, free and bound phenolics, anthocyanins, proanthocyanidins, and free radical scavenging capacity were analysed. The traditional rice with brown pericarp exhibited an increase in cooking time and free phenolics content, while rice with black pericarp exhibited a reduction in cooking time after six months of storage at the highest studied temperature of 40°C. There as increases in ferulic acid levels occurred as a function of storage temperature. Red pericarp rice grains showed decreased antioxidant capacity against ABTS radical for the soluble phenolic fraction with increased time and storage temperature. Copyright © 2017 Elsevier Ltd. All rights reserved.

Changes in nutritional and physico-chemical properties of pearl millet (Pennisetum glaucum) Ex-Borno variety flour as a result of malting.

PubMed

Obadina, Adewale O; Arogbokun, Christianah A; Soares, Antonio O; de Carvalho, Carlos Wanderlei Piler; Barboza, Henriqueta Talita; Adekoya, Ifeoluwa O

2017-12-01

The effect of malting periods on the nutritional composition and physico-chemical properties of flour from pearl millet (Ex-Borno) variety was evaluated. Grains were steeped at 25 °C for 24 h and germinated for different durations (12, 24, 36, 48, 60, 72, 84 and 96 h) before kilning at 55 °C for 18 h. The kilned seeds were devegetated, milled, sieved and analysed for their proximate composition, amino acid composition, total phenolic content, functional and pasting properties. The carbohydrate, fat and total phenolic contents of the pearl millet flour samples decreased while protein content increased with increased malting periods. Leucine was the dominant amino acid in the flour and 48 h-malted flour had the highest total amino acid (6.72). Peak viscosity significantly decreased as the malting period increased. Solubility index, pasting temperature and phenolic content of the flours ranged from 5.13 to 17.24%, 69.05 to 89.5 °C and 130.20 to 169.90 mg/100 g, respectively. Malting offers a means of improving the nutritional profile of Ex-Borno pearl millet flour with an increased protein and fibre and reduced fat content. Malting also enhanced the functional and pasting properties of the flour.

Interfacial Structure and Properties of Wood/Polypropylene Composites

Treesearch

Timothy G. Rials; Michael P. Wolcott; Suzhow Yin

2000-01-01

Composite wood products have traditionally relied on thermosetting polymers like phenol-formaldehyde and urea-formaldehyde resins as binders. The continuing need to effectively utilize lignocellulosic fiber from low-quality hardwoods and from recycling streams has prompted consideration of new composites based on thermoplastic polymers [1,2]. Much of the development...

Chemical Composition and Biological Activities of Mono- and Heterofloral Bee Pollen of Different Geographical Origins

PubMed Central

Araújo, Jucilene Silva; Chambó, Emerson Dechechi; Costa, Maria Angélica Pereira de Carvalho; Cavalcante da Silva, Samira Maria Peixoto; Lopes de Carvalho, Carlos Alfredo; M. Estevinho, Leticia

2017-01-01

Recent research shows variations in pollen chemical constituents and, consequently, in their therapeutic properties. Mono and multifloral bee pollen extracts were investigated for antioxidant and enzyme inhibitory activity properties, phenolic compounds and fatty acid composition. Generally, Eucalyptus spp. and multifloral extracts exhibited potent inhibitory activity against α-amylase, acetylcholinesterase, tyrosinase, lipoxygenase, lipase and hyaluronidase. On the other hand, Miconia spp. demonstrated higher antihemolytic activity. Cocos nucifera and Miconia spp. extracts exhibited important antioxidant properties in the different assays (ABTS, DPPH, β-carotene/linoleic acid and reducing power). Moreover, these extracts had greater amounts of total phenols and flavonoids in comparison to others. The increase in antioxidant activity (decrease in EC50 values) was accompanied by an increase in the amount of total phenols in the extracts. The pollen extracts contained linoleic acid and α-linolenic acid as major fatty acids, followed by palmitic acid, and oleic acid. In this study, differences were observed in both chemical constituents and biological activities of the samples related to the geographical and botanical origin of bee pollen. PMID:28448467

Total Phenolic, Phenolic Acid, Anthocyanin, Flavan-3-ol, and Flavonol Profiles and Antioxidant Properties of Pinto and Black Beans ( Phaseolus vulgaris L.) as Affected by Thermal Processing.

PubMed

Xu, Baojun; Chang, Sam K C

2009-06-10

The effects of boiling and steaming processes at atmospheric and high pressures on the phenolic components and antioxidant properties of pinto and black beans were investigated. In comparison to the original raw beans, all processing methods caused significant (p < 0.05) decreases in total phenolic content (TPC), total flavonoid content (TFC), condensed tannin content (CTC), monomeric anthocyanin content (MAC), DPPH free-radical scavenging activity (DPPH), ferric-reducing antioxidant power (FRAP), and oxygen radical absorbing capacity (ORAC) values in both pinto and black beans. Steaming processing resulted in a greater retention of TPC, DPPH, FRAP, and ORAC values than the boiling processes in both pinto and black beans. To further investigate how thermal processing affected phenolic compositions and to elucidate the contribution of individual phenolic compounds to antioxidant properties, phenolic acids, anthocyanins, flavan-3-ols, and flavonols were quantitatively analyzed by high-performance liquid chromatography (HPLC). All thermal processing significantly (p < 0.05) affected individual phenolic acids, anthocyanins, flavan-3-ols, and flavonols, significantly (p < 0.05) reduced total phenolic acid contents in both pinto and black beans and total flavonol contents in pinto beans, and dramatically reduced anthocyanin contents in black beans. Phenolic acids and flavonols may play important roles on the overall antioxidant activities of pinto beans, while anthocyanins, flavan-3-ols, and flavonols may play important roles on the overall antioxidant activities of black beans.

Activation of Magnesium Lignosulfonate and Kraft Lignin: Influence on the Properties of Phenolic Resin-Based Composites for Potential Applications in Abrasive Materials

PubMed Central

Klapiszewski, Lukasz; Jamrozik, Artur; Strzemiecka, Beata; Matykiewicz, Danuta; Voelkel, Adam; Jesionowski, Teofil

2017-01-01

Magnesium lignosulfonate and kraft lignin were activated by different oxidizing agents for use in phenolic resin composites used for the production of abrasive components. The physicochemical properties of the oxidized materials were analyzed by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), dynamic mechanical-thermal analysis (DMTA) and inverse gas chromatography (IGC). The homogeneity of the model abrasive composites containing the studied products was assessed based on observations obtained using a scanning electron microscope (SEM). FTIR and XPS analysis of the oxidized products indicated that the activation process leads mainly to the formation of carbonyl groups. The IGC technique was used to assess changes in the surface energy and the acid–base properties of the studied biopolymers. The changes in the acid–base properties suggest that more groups acting as electron donors appear on the oxidized surface of the materials. DMTA studies showed that the model composites with 5% magnesium lignosulfonate oxidized by H2O2 had the best thermomechanical properties. Based on the results it was possible to propose a hypothetical mechanism of the oxidation of the natural polymers. The use of such oxidized products may improve the thermomechanical properties of abrasive articles. PMID:28594358

Physicochemical Characterization of Functional Lignin–Silica Hybrid Fillers for Potential Application in Abrasive Tools

PubMed Central

Strzemiecka, Beata; Klapiszewski, Łukasz; Jamrozik, Artur; Szalaty, Tadeusz J.; Matykiewicz, Danuta; Sterzyński, Tomasz; Voelkel, Adam; Jesionowski, Teofil

2016-01-01

Functional lignin–SiO2 hybrid fillers were prepared for potential application in binders for phenolic resins, and their chemical structure was characterized. The properties of these fillers and of composites obtained from them with phenolic resin were compared with those of systems with lignin or silica alone. The chemical structure of the materials was investigated by Fourier transform infrared spectroscopy (FT-IR) and carbon-13 nuclear magnetic resonance spectroscopy (13C CP MAS NMR). The thermal stability of the new functional fillers was examined by thermogravimetric analysis–mass spectrometry (TG-MS). Thermo-mechanical properties of the lignin–silica hybrids and resin systems were investigated by dynamic mechanical thermal analysis (DMTA). The DMTA results showed that abrasive composites with lignin–SiO2 fillers have better thermo-mechanical properties than systems with silica alone. Thus, fillers based on lignin might provide new, promising properties for the abrasive industry, combining the good properties of lignin as a plasticizer and of silica as a filler improving mechanical properties. PMID:28773639

Quantification of phenolic acids and antioxidant potential of inbred, hybrid and composite cultivars of maize under different nitrogen regimes.

PubMed

Ganie, Arshid Hussain; Yousuf, Peerzada Yasir; Ahad, Amjid; Pandey, Renu; Ahmad, Sayeed; Aref, Ibrahim M; Noor, Jewel Jameeta; Iqbal, Muhammad

2016-11-01

Maize (Zea mays L.) is a multipurpose crop, which is immensely used worldwide for its nutritional as well as medicinal properties. This study evaluates the effect of varying concentrations of nitrogen (N) on accumulation of phenolic acids and antioxidant activity in different maize cultivars, including inbreds, hybrids and a composite, which were grown in natural light under controlled temperature (30°C/20°C D/N) and humidity (80%), with sufficient (4.5mM) and low (0.05mM) nitrogen supply. Seeds of different cultivars were powdered and extracted in a methanol:water (80:20) mixture through reflux at 60-75°C, and the extracts obtained were subjected to high performance thin layer chromatography (HPTLC), using ethyl acetate: acetic acid: formic acid: water (109:16:12:31) solvent system for the separation of phenolic acids. Antioxidant activity of the extracts was determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and H2O2-scavenging activity assays. At sufficient nitrogen condition, the contents of different phenolic acids were higher in the composite cultivar (8.7 mg g-1 d.wt. in gallic acid to 39.3 mg g-1 d.wt. in cinnamic and salicylic acids) than in inbreds and hybrids. Under low nitrogen condition, the phenolic acids contents declined significantly in inbreds and hybrids, but remained almost unaffected in the composite. The antioxidant activity was also the maximum in the composite, and declined similarly as phenolic acids under low nitrogen supply, showing a significant reduction in inbreds and hybrids only. Therefore, the maize composite has a potential for being used as a nutraceutical in human-health sector.

Flame-retardant composite materials

NASA Technical Reports Server (NTRS)

Kourtides, Demetrius A.

1991-01-01

The properties of eight different graphite composite panels fabricated using four different resin matrices and two types of graphite reinforcement are described. The resin matrices included: VPSP/BMI, a blend of vinylpolystyryl pyridine and bismaleimide; BMI, a bismaleimide; and phenolic and PSP, a polystyryl pyridine. The graphite fiber used was AS-4 in the form of either tape or fabric. The properties of these composites were compared with epoxy composites. It was determined that VPSP/BMI with the graphite tape was the optimum design giving the lowest heat release rate.

Recycling of phenol from aqueous solutions by pervaporation with ZSM-5/PDMS/PVDF hollow fiber composite membrane

NASA Astrophysics Data System (ADS)

Li, Dan; Yao, Jie; Sun, Hao; Liu, Bing; van Agtmaal, Sjack; Feng, Chunhui

2018-01-01

Zeolite (ZSM-5)/polydimethylsiloxane (PDMS)/polyvinylidene fluoride (PVDF) hollow fiber composite membrane was prepared by dynamic negative pressure. The influence of ZSM-5 silanization, coating time and concentration of ZSM-5 on the resulting pervaporation (PV) performance of composite membranes was investigated. The contact angle (CA) was used to measure surface hydrophobic property and it was found that the water contact angle of the membrane was increased significantly from 99° to 132° when the concentration of ZSM-5 increased from 0% to 50%. The morphology of the membrane was characterized by scanning electron microscope (SEM) and those SEM images illustrated that the thickness of the separating layer has obvious differences at varying coating times. Furthermore, the membranes were investigated in PV process to recycle phenol from aqueous solutions as feed mixtures. The impact of phenol concentration in feed, temperature and pressure of penetration side on the PV performance of membrane was studied systematically. When the ZSM-5 concentration was 40% and the coating time was 60 min, separation factor and phenol permeability were 4.56 and 5.78 g/(m2 h), respectively. ZSM-5/PDMS/PVDF membrane significantly improved the recovery efficiency of phenols.

Relationship between red wine grades and phenolics. 1. Tannin and total phenolics concentrations.

PubMed

Mercurio, Meagan D; Dambergs, Robert G; Cozzolino, Daniel; Herderich, Markus J; Smith, Paul A

2010-12-08

Measuring chemical composition is a common approach to support decisions about allocating foods and beverages to grades related to market value. Red wine is a particularly complex beverage, and multiple compositional attributes are needed to account for its sensory properties, including measurement of key phenolic components such as anthocyanins, total phenolics, and tannin, which are related to color and astringency. Color has been shown to relate positively to red wine grade; however, little research has been presented that explores the relationship between astringency-related components such as total phenolic or tannin concentration and wine grade. The aim of this research has been to investigate the relationship between the wine grade allocations of commercial wineries and total phenolic and tannin concentrations, respectively, in Australian Shiraz and Cabernet Sauvignon wines. Total phenolic and tannin concentrations were determined using the methyl cellulose precipitable (MCP) tannin assay and then compared to wine grade allocations made by winemaker panels during the companies' postvintage allocation process. Data were collected from wines produced by one Australian wine company over the 2005, 2006, and 2007 vintages and by a further two companies in 2007 (total wines = 1643). Statistical analysis revealed a positive trend toward higher wine grade allocation and wines that had higher concentrations of both total phenolics and tannin, respectively. This research demonstrates that for these companies, in general, Cabernet Sauvignon and Shiraz wines allocated to higher market value grades have higher total phenolics and higher tannin concentrations and suggests that these compositional parameters should be considered in the development of future multiparameter decision support systems for relevant commercial red wine grading processes. In addition, both tannin and total phenolics would ideally be included because although, in general, a positive relationship exists between the two parameters, this relationship does not hold for all wine styles.

Thermostructural responses of carbon phenolics in a restrained thermal growth test

NASA Technical Reports Server (NTRS)

Wang, C. Jeff

1992-01-01

The thermostructural response of carbon phenolic components in a solid rocket motor (SRM) is a complex process. It involves simultaneous heat and mass transfer along with chemical reactions in a multiphase system with time-dependent material properties and boundary conditions. In contrast to metals, the fracture of fiber-reinforced composites is characterized by the initiation and progression of multiple failures of different modes such as matrix cracks, interfacial debonding, fiber breaks, and delamination. The investigation of thermostructural responses of SRM carbon phenolics is further complicated by different failure modes under static and dynamic load applications. Historically, there have been several types of post-firing anomalies found in the carbon phenolic composites of the Space Shuttle SRM nozzle. Three major failure modes which have been observed on SRM nozzles are pocketing (spallation), ply-lift, and wedge-out. In order to efficiently control these anomalous phenomena, an investigation of fracture mechanisms under NASA/MSFC RSRM (Redesigned Solid Rocket Motor) and SPIP (Solid Propulsion Integrity Program) programs have been conducted following each anomaly. This report reviews the current progress in understanding the effects of the thermostructural behavior of carbon phenolics on the failure mechanisms of the SRM nozzle. A literature search was conducted and a technical bibliography was developed to support consolidation and assimilation of learning from the RSRM and SPIP investigation efforts. Another important objective of this report is to present a knowledge-based design basis for carbon phenolics that combines the analyses of thermochemical decomposition, pore pressure stresses, and thermostructural properties. Possible areas of application of the knowledge-based design include critical material properties development, nozzle component design, and SRM materials control.

Investigation of the effects of NaOH dopant level on the physical and mechanical properties of carbon/phenolic composite material

NASA Technical Reports Server (NTRS)

Clinton, R. G., Jr.

1985-01-01

The near-catastrophic erosion of the STS-8A solid rocket booster nozzle was the instigating factor in the recent, and on-going, intensive investigation of carbon/phenolic composite materials. Much of this effort has been focused on the effect of sodium contamination on the carbon fibers. It is known that sodium acts as a catalyst in the oxidation of the fibers at elevated temperatures. A study was undertaken to determine what changes were caused by variation in sodium content. Investigations were conducted in three areas: (1) phenolic resin; (2) carbon/phenolic prepreg; and (3) cured laminates. Due to the exploratory nature of the studies, a variety of tests in addition to those normally run in production facilities were considered. The experimental methodologies and results of these experiments are discussed, and recommendations for improving techniques and extending the research program are presented.

Fruit Phenolic Profiling: A New Selection Criterion in Olive Breeding Programs

PubMed Central

Pérez, Ana G.; León, Lorenzo; Sanz, Carlos; de la Rosa, Raúl

2018-01-01

Olive growing is mainly based on traditional varieties selected by the growers across the centuries. The few attempts so far reported to obtain new varieties by systematic breeding have been mainly focused on improving the olive adaptation to different growing systems, the productivity and the oil content. However, the improvement of oil quality has rarely been considered as selection criterion and only in the latter stages of the breeding programs. Due to their health promoting and organoleptic properties, phenolic compounds are one of the most important quality markers for Virgin olive oil (VOO) although they are not commonly used as quality traits in olive breeding programs. This is mainly due to the difficulties for evaluating oil phenolic composition in large number of samples and the limited knowledge on the genetic and environmental factors that may influence phenolic composition. In the present work, we propose a high throughput methodology to include the phenolic composition as a selection criterion in olive breeding programs. For that purpose, the phenolic profile has been determined in fruits and oils of several breeding selections and two varieties (“Picual” and “Arbequina”) used as control. The effect of three different environments, typical for olive growing in Andalusia, Southern Spain, was also evaluated. A high genetic effect was observed on both fruit and oil phenolic profile. In particular, the breeding selection UCI2-68 showed an optimum phenolic profile, which sums up to a good agronomic performance previously reported. A high correlation was found between fruit and oil total phenolic content as well as some individual phenols from the two different matrices. The environmental effect on phenolic compounds was also significant in both fruit and oil, although the low genotype × environment interaction allowed similar ranking of genotypes on the different environments. In summary, the high genotypic variance and the simplified procedure of the proposed methodology for fruit phenol evaluation seems to be convenient for breeding programs aiming at obtaining new cultivars with improved phenolic profile. PMID:29535752

Fruit Phenolic Profiling: A New Selection Criterion in Olive Breeding Programs.

PubMed

Pérez, Ana G; León, Lorenzo; Sanz, Carlos; de la Rosa, Raúl

2018-01-01

Olive growing is mainly based on traditional varieties selected by the growers across the centuries. The few attempts so far reported to obtain new varieties by systematic breeding have been mainly focused on improving the olive adaptation to different growing systems, the productivity and the oil content. However, the improvement of oil quality has rarely been considered as selection criterion and only in the latter stages of the breeding programs. Due to their health promoting and organoleptic properties, phenolic compounds are one of the most important quality markers for Virgin olive oil (VOO) although they are not commonly used as quality traits in olive breeding programs. This is mainly due to the difficulties for evaluating oil phenolic composition in large number of samples and the limited knowledge on the genetic and environmental factors that may influence phenolic composition. In the present work, we propose a high throughput methodology to include the phenolic composition as a selection criterion in olive breeding programs. For that purpose, the phenolic profile has been determined in fruits and oils of several breeding selections and two varieties ("Picual" and "Arbequina") used as control. The effect of three different environments, typical for olive growing in Andalusia, Southern Spain, was also evaluated. A high genetic effect was observed on both fruit and oil phenolic profile. In particular, the breeding selection UCI2-68 showed an optimum phenolic profile, which sums up to a good agronomic performance previously reported. A high correlation was found between fruit and oil total phenolic content as well as some individual phenols from the two different matrices. The environmental effect on phenolic compounds was also significant in both fruit and oil, although the low genotype × environment interaction allowed similar ranking of genotypes on the different environments. In summary, the high genotypic variance and the simplified procedure of the proposed methodology for fruit phenol evaluation seems to be convenient for breeding programs aiming at obtaining new cultivars with improved phenolic profile.

Fabrication and testing of fire resistant graphite composite panels

NASA Technical Reports Server (NTRS)

Roper, W. D.

1986-01-01

Eight different graphite composite panels were fabricated using four different resin matrices. The resin matrices included Hercules 71775, a blend of vinylpolystyrpyridine and bismaleimide, H795, a bismaleimide, Cycom 6162, a phenolic, and PSP 6022m, a polystyrylpyridine. Graphite panels were fabricated using fabric or unidirectional tape. Described are the processes for preparing these panels and some of their mechanical, thermal and flammability properties. Panel properties are compared with state-of-the-art epoxy fiberglass composite panels.

Asphaltenes-based polymer nano-composites

DOEpatents

Bowen, III, Daniel E

2013-12-17

Inventive composite materials are provided. The composite is preferably a nano-composite, and comprises an asphaltene, or a mixture of asphaltenes, blended with a polymer. The polymer can be any polymer in need of altered properties, including those selected from the group consisting of epoxies, acrylics, urethanes, silicones, cyanoacrylates, vulcanized rubber, phenol-formaldehyde, melamine-formaldehyde, urea-formaldehyde, imides, esters, cyanate esters, allyl resins.

Sempervivum davisii: phytochemical composition, antioxidant and lipase-inhibitory activities.

PubMed

Uzun, Yusuf; Dalar, Abdullah; Konczak, Izabela

2017-12-01

Sempervivum davisii Muirhead (Crassulaceae) is a traditional medicinal herb from Eastern Anatolia. To date the composition of phytochemicals and physiological properties of this herb were not subjected to any research. This study identifies compounds in S. davisii hydrophilic extracts and evaluates their potential biological properties. Ethanol-based lyophilized extracts were obtained from aerial parts of plant (10 g of ground dry plant material in 200 mL of acidified aqueous ethanol, shaken for 2 h at 22 °C with supernatant collected and freeze-dried under vacuum). Phytochemical composition was investigated by liquid chromatography mass spectrometry (LC-MS/MS, phenolics) and gas chromatography mass spectrometry (GC-MS, volatiles). Phenolic compounds were quantified by high-performance liquid chromatography (HPLC) and the Folin-Ciocalteu assay. Subsequently, antioxidant capacity [ferric reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC) assays] and enzyme inhibitory properties (isolated porcine pancreatic lipase) of the extracts were determined. Polyphenolic compounds were the main constituents of lyophilized extracts, among which kaempferol glycosides and quercetin hexoside dominated. The extracts exhibited potent antioxidant (FRAP values of 1925.2-5973.3 μM Fe 2+ /g DW; ORAC values of 1858.5-4208.7 μM Trolox Eq./g DW) and moderate lipase inhibitory (IC 50 : 11.6-2.96 mg/mL) activities. Volatile compounds (nonanal, dehydroxylinalool oxide isomers, 2-decenal, 2-undecenal, 2,6-di-tetr-butylphenol) were also found. Phenolic compounds with the dominating kaempferol and quercetin derivatives are the sources of potent antioxidant properties of S. davisii hydrophilic extracts. The extracts exhibit moderate inhibitory properties towards isolated pancreatic lipase.

The relationship between metal composition, phenolic acid and flavonoid content in Imleria badia from non-polluted and polluted areas.

PubMed

Gąsecka, Monika; Rzymski, Piotr; Mleczek, Mirosław; Siwulski, Marek; Budzyńska, Sylwia; Magdziak, Zuzanna; Niedzielski, Przemysław; Sobieralski, Krzysztof

2017-03-04

The aim of this study was to determine the elemental composition, phenolic content and composition and antioxidant properties of Imleria badia (Fr.) Vizzini (former names Boletus badius (Fr.) Fr., and Xerocomus badius (Fr.) E.-J. Gilbert) fruiting bodies collected from sites with different levels of pollution. Imleria badia was relatively tolerant to soil contamination with toxic elements and was able to grow in As, Cd, Hg and Pb concentrations exceeding 15, 2.9, 0.4 and 77 mg kg -1 , respectively. The concentration of elements in soil was reflected in the element content in I. badia. The fruiting bodies from polluted sites exhibited significantly higher content of all the analyzed elements. Among 21 individual phenolic compounds only protocatechiuc and caffeic acids, and quercetin were determined in fruiting bodies of I. badia. The differences between the concentration of the quantified phenolic compounds and the total flavonoid content in fruiting bodies of I. badia from unpolluted and polluted sites were not significant. However, the greatest total phenolic content was found in fruiting bodies from the polluted areas. The antioxidative capacity of mushrooms collected from heavily polluted sites was lower than those growing in unpolluted areas. The concentrations of some metals in soil and fruiting soil were positively correlated with phenolic content and IC 50 .

Elaboration of chitosan/activated carbon composites for the removal of organic micropollutants from waters.

PubMed

Venault, A; Vachoud, L; Pochat, C; Bouyer, D; Faur, C

2008-12-01

Composite hydrogels were prepared by a wet-casting process by blending a biopolymer, chitosan, with activated carbon (AC) for use in water treatment. Adsorption properties of the composite gels for an organic micro-pollutant (phenol) which may be encountered in wastewaters was studied with an experimental design approach as a function of: - the concentration of raw materials and thus the AC weight within the chitosan matrix. - the accessibility of AC in the polymeric matrix, which is assumed to be related to the coating and thus to the pH of the immersion bath. ESEM observations showed that at a higher pH of gelation (pH = 14), AC particles were entrapped at the surface of the polymer matrix because of a faster gelation kinetic than at a lower pH (13.3). Adsorption kinetic tests showed that phenol adsorption occurred according to two mechanisms. During the first step, phenol molecules were adsorbed by the AC particles located at the surface. The second step corresponded to a slow diffusion through chitosan chains leading to an adsorption by AC particles entrapped within the polymeric matrix coupled to an adsorption on to the chitosan. A mass transfer model was used to describe this two-step adsorption phenomenon. However, due to a heterogeneous coating of AC by chitosan, this phenomenon was not supported by experimental design results: the initial kinetic coefficients were associated with a high experimental error which didn't allow for an analysis of the influence of elaboration parameters on kinetic coefficients. Regardling equilibrium adsorption properties, it was shown that composite gels were good adsorbents for phenol with removal ranging from 94% to 98% corresponding to adsorption capacities from 30 to 41 mg g(-1). The pH of the immersion bath had no influence on equilibrium adsorption properties, contrary to the AC weight within the chitosan matrix which wasdemonstrated to influence significantly adsorption capacities. Because carbon particles may improve mechanical properties, mechanical tests were carried out on the composite gels. For a total amount of dried matter in the compositekept constant, the increase in chitosan content led to an increase in the mechanical properties, because of an increase in thenumber of interactions between chitosan chains. The influence of sonication during the stirring step, leading to a better homogenisation of AC particules within the polymer matrix, was also examined.

A Phenolic Extract Obtained from Methyl Jasmonate-Treated Strawberries Enhances Apoptosis in a Human Cervical Cancer Cell Line.

PubMed

Spagnuolo, Carmela; Flores, Gema; Russo, Gian Luigi; Ruiz Del Castillo, Maria Luisa

2016-10-01

In the present study, we evaluated the effect of methyl jasmonate (MeJA) treatment on strawberry phenolic composition. Strawberry extracts contain a mixture of phenolic compounds possessing several biological properties. We demonstrated that these extracts were more effective in inducing apoptosis in HeLa cells compared to phenolic preparations derived from untreated strawberries. Treatment of strawberries with 0.5% MeJA resulted in increased polyphenols content (from 7.4 to 8.6 mM quercetin equivalents) and antioxidant properties (from 3.9 to 4.6 mM quercetin equivalents). The identification and quantification of phenolic compounds by liquid chromatography-mass spectrometry in the strawberry extracts showed that cyanidin glucoside, pelargonidin glucoside, and ellagic glucoside acid were significantly higher in strawberries treated with MeJA. Phenolic extracts from MeJA-treated strawberries significantly decreased the cell viability in HeLa cells, compared to extracts derived from untreated fruits. We hypothesized that the enhanced apoptotic activity of MeJA-treated strawberries was due to a synergistic or additive effect of different phenolic compounds present in the extract, rather than the activity of a single molecule.

Cocoa and Grape Seed Byproducts as a Source of Antioxidant and Anti-Inflammatory Proanthocyanidins

PubMed Central

Cádiz-Gurrea, María De La Luz; Borrás-Linares, Isabel; Lozano-Sánchez, Jesús; Joven, Jorge; Fernández-Arroyo, Salvador; Segura-Carretero, Antonio

2017-01-01

Phenolic compounds, which are secondary plant metabolites, are considered an integral part of the human diet. Physiological properties of dietary polyphenols have come to the attention in recent years. Especially, proanthocyanidins (ranging from dimers to decamers) have demonstrated potential interactions with biological systems, such as antiviral, antibacterial, molluscicidal, enzyme-inhibiting, antioxidant, and radical-scavenging properties. Agroindustry produces a considerable amount of phenolic-rich sources, and the ability of polyphenolic structures to interacts with other molecules in living organisms confers their beneficial properties. Cocoa wastes and grape seeds and skin byproducts are a source of several phenolic compounds, particularly mono-, oligo-, and polymeric proanthocyanidins. The aim of this work is to compare the phenolic composition of Theobroma cacao and Vitis vinifera grape seed extracts by high pressure liquid chromatography coupled to a quadrupole time-of-flight mass spectrometer and equipped with an electrospray ionization interface (HPLC-ESI-QTOF-MS) and its phenolic quantitation in order to evaluate the proanthocyanidin profile. The antioxidant capacity was measured by different methods, including electron transfer and hydrogen atom transfer-based mechanisms, and total phenolic and flavan-3-ol contents were carried out by Folin–Ciocalteu and Vanillin assays. In addition, to assess the anti-inflammatory capacity, the expression of MCP-1 in human umbilical vein endothelial cells was measured. PMID:28208630

Cocoa and Grape Seed Byproducts as a Source of Antioxidant and Anti-Inflammatory Proanthocyanidins.

PubMed

Cádiz-Gurrea, María De La Luz; Borrás-Linares, Isabel; Lozano-Sánchez, Jesús; Joven, Jorge; Fernández-Arroyo, Salvador; Segura-Carretero, Antonio

2017-02-10

Phenolic compounds, which are secondary plant metabolites, are considered an integral part of the human diet. Physiological properties of dietary polyphenols have come to the attention in recent years. Especially, proanthocyanidins (ranging from dimers to decamers) have demonstrated potential interactions with biological systems, such as antiviral, antibacterial, molluscicidal, enzyme-inhibiting, antioxidant, and radical-scavenging properties. Agroindustry produces a considerable amount of phenolic-rich sources, and the ability of polyphenolic structures to interacts with other molecules in living organisms confers their beneficial properties. Cocoa wastes and grape seeds and skin byproducts are a source of several phenolic compounds, particularly mono-, oligo-, and polymeric proanthocyanidins. The aim of this work is to compare the phenolic composition of Theobroma cacao and Vitis vinifera grape seed extracts by high pressure liquid chromatography coupled to a quadrupole time-of-flight mass spectrometer and equipped with an electrospray ionization interface (HPLC-ESI-QTOF-MS) and its phenolic quantitation in order to evaluate the proanthocyanidin profile. The antioxidant capacity was measured by different methods, including electron transfer and hydrogen atom transfer-based mechanisms, and total phenolic and flavan-3-ol contents were carried out by Folin-Ciocalteu and Vanillin assays. In addition, to assess the anti-inflammatory capacity, the expression of MCP-1 in human umbilical vein endothelial cells was measured.

Recent Development of Flax Fibres and Their Reinforced Composites Based on Different Polymeric Matrices

PubMed Central

Zhu, Jinchun; Zhu, Huijun; Njuguna, James; Abhyankar, Hrushikesh

2013-01-01

This work describes flax fibre reinforced polymeric composites with recent developments. The properties of flax fibres, as well as advanced fibre treatments such as mercerization, silane treatment, acylation, peroxide treatment and coatings for the enhancement of flax/matrix incompatibility are presented. The characteristic properties and characterizations of flax composites on various polymers including polypropylene (PP) and polylactic acid, epoxy, bio-epoxy and bio-phenolic resin are discussed. A brief overview is also given on the recent nanotechnology applied in flax composites. PMID:28788383

Exploratory Characterization of Phenolic Compounds with Demonstrated Anti-Diabetic Activity in Guava Leaves at Different Oxidation States

PubMed Central

Díaz-de-Cerio, Elixabet; Verardo, Vito; Gómez-Caravaca, Ana María; Fernández-Gutiérrez, Alberto; Segura-Carretero, Antonio

2016-01-01

Psidium guajava L. is widely used like food and in folk medicine all around the world. Many studies have demonstrated that guava leaves have anti-hyperglycemic and anti-hyperlipidemic activities, among others, and that these activities belong mainly to phenolic compounds, although it is known that phenolic composition in guava tree varies throughout seasonal changes. Andalusia is one of the regions in Europe where guava is grown, thus, the aim of this work was to study the phenolic compounds present in Andalusian guava leaves at different oxidation states (low, medium, and high). The phenolic compounds in guava leaves were determined by HPLC-DAD-ESI-QTOF-MS. The results obtained by chromatographic analysis reported that guava leaves with low degree of oxidation had a higher content of flavonols, gallic, and ellagic derivatives compared to the other two guava leaf samples. Contrary, high oxidation state guava leaves reported the highest content of cyanidin-glucoside that was 2.6 and 15 times higher than guava leaves with medium and low oxidation state, respectively. The QTOF platform permitted the determination of several phenolic compounds with anti-diabetic properties and provided new information about guava leaf phenolic composition that could be useful for nutraceutical production. PMID:27187352

Exploratory Characterization of Phenolic Compounds with Demonstrated Anti-Diabetic Activity in Guava Leaves at Different Oxidation States.

PubMed

Díaz-de-Cerio, Elixabet; Verardo, Vito; Gómez-Caravaca, Ana María; Fernández-Gutiérrez, Alberto; Segura-Carretero, Antonio

2016-05-11

Psidium guajava L. is widely used like food and in folk medicine all around the world. Many studies have demonstrated that guava leaves have anti-hyperglycemic and anti-hyperlipidemic activities, among others, and that these activities belong mainly to phenolic compounds, although it is known that phenolic composition in guava tree varies throughout seasonal changes. Andalusia is one of the regions in Europe where guava is grown, thus, the aim of this work was to study the phenolic compounds present in Andalusian guava leaves at different oxidation states (low, medium, and high). The phenolic compounds in guava leaves were determined by HPLC-DAD-ESI-QTOF-MS. The results obtained by chromatographic analysis reported that guava leaves with low degree of oxidation had a higher content of flavonols, gallic, and ellagic derivatives compared to the other two guava leaf samples. Contrary, high oxidation state guava leaves reported the highest content of cyanidin-glucoside that was 2.6 and 15 times higher than guava leaves with medium and low oxidation state, respectively. The QTOF platform permitted the determination of several phenolic compounds with anti-diabetic properties and provided new information about guava leaf phenolic composition that could be useful for nutraceutical production.

Exploring reserve lots of Cymbopogon citratus, Aloysia citrodora and Thymus × citriodorus as improved sources of phenolic compounds.

PubMed

Rita, Ingride; Pereira, Carla; Barros, Lillian; Ferreira, Isabel C F R

2018-08-15

Given the increasing consumers demand for novelty, tea companies have been presenting new added value products such as reserve lots of aromatic plants. Herein, infusions from different lots of three aromatic plants were assessed in terms of phenolic composition (HPLC-DAD-ESI/MS) and antioxidant properties (reducing power, free radical scavenging and lipid peroxidation inhibition capacity). Cymbopogon citratus (C. citratus; main compound 5-O-caffeoylquinic acid) and Aloysia citrodora (A. citrodora; prevalence of verbascoside) reserve lots revealed higher phenolic compounds concentration than the respective standard lots. Thymus × citriodorus (T. citriodorus; main compound rosmarinic acid) standard lot presented higher amounts of phenolic acids than the reserve lot, nonetheless, total flavonoids and phenolic compounds were not significantly different. The differences between both lots antioxidant activity were more noticeable in C. citratus, with the reserve lot presenting the highest activity. This study provides evidence of the differences between these plants chemical composition and bioactivity depending on the harvesting conditions. Copyright © 2018 Elsevier Ltd. All rights reserved.

Edible Neotropical Blueberries: Antioxidant and Compositional Fingerprint Analysis

PubMed Central

DASTMALCHI, KEYVAN; FLORES, GEMA; PETROVA, VANYA; PEDRAZA-PEÑALOSA, PAOLA; KENNELLY, EDWARD J.

2012-01-01

Edible blueberry species are well recognized for their potential health benefits. Ericaceae fruits including the North American highbush blueberry (Vaccinium corymbosum L.) and five less common edible blueberry relatives from the New World tropics, Anthopterus wardii Ball, Cavendishia grandifolia Hoerld, Macleania coccoloboides A. C. Sm., Sphyrospermum buxifolium Poepp. & Endl., and Sphyrospermum cordifolium Benth, were investigated for their antioxidant properties and phenolic profiles. The Neotropical berries C. grandifolia and A. wardii exhibited significantly higher DPPH• and ABTS•+ scavenging and iron chelation activities than V. corymbosum. Total phenolic content and HPLC-PDA compositional fingerprint analyses were also carried out. Significant correlations were observed among total phenolic contents, DPPH• and ABTS•+ scavenging, and iron chelation activities. Using HPLC-PDA, the phenolic constituents in the berries were identified as chlorogenic acid, p-coumaric acid, hyperoside, quercetin-3-O-glucoside, isoorientin, isovitexin, orientin and vitexin. Principal components analysis reduced the dimensions of antioxidant and total phenolic data to two components, which accounted for 95% of total variation among the six fruits. Each fruit species formed its own cluster, and therefore the antioxidant profile of each species was shown to be distinct. PMID:21391608

Enhanced photocatalytic degradation of phenol and photogenerated charges transfer property over BiOI-loaded ZnO composites.

PubMed

Jiang, Jingjing; Wang, Hongtao; Chen, Xiaodong; Li, Shuo; Xie, Tengfeng; Wang, Dejun; Lin, Yanhong

2017-05-15

In this paper, a series of BiOI/ZnO photocatalysts containing various BiOI contents were prepared by a facile two-step synthetic method. The structure and crystal phase, morphology, surface element analysis, optical property of as-prepared samples are measured by X-ray diffraction (XRD), Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and UV-Vis diffuse reflectance spectrometry (DRS). BiOI/ZnO photocatalytic activities of the prepared photocatalysts were evaluated by photocatalytic degradation of phenol under simulated light irradiation. The phenol degradation rate reached 99.9% within 2h under simulated solar light irradiation. The probable photocatalytic mechanism of composites photocatalysts is discussed by active species trapping experiments, the surface photovoltage (SPV), the transient photovoltage (TPV) and photoluminescence (PL) measurements. The results manifest that the superior photocatalytic activity of BiOI/ZnO composites is derived from the strong internal electric field between BiOI and ZnO, which is beneficial for the effective separation and transfer of photogenerated charges in ZnO. Moreover, the loading of BiOI on the surface of ZnO inhibited the recombination of photogenerated charge carriers in ZnO, resulting in excellent photocatalytic activity. On the contrary, the effect of an extension of the light absorption range induced by the introduction of BiOI on the phenol degradation activity is not significant. Copyright © 2017 Elsevier Inc. All rights reserved.

Chemical composition of five commercial gynostemma pentaphyllum samples and their radical scavenging, antiproliferative, and anti-inflammatory properties

USDA-ARS?s Scientific Manuscript database

Five Gynostemma pentaphyllum (GP) samples were investigated: their chemical composition and their antioxidant, antiproliferative, and anti-inflammatory effects were compared. Extracts (50% acetone, 75% ethanol, and 100% ethanol) of the five GP samples (GP1-5) differed in their total phenolic, sapon...

Development of improved asbestos reinforced phenolic insulating composites (optimization of physical properties as a function of molding technique and post cure conditions)

NASA Technical Reports Server (NTRS)

Hedges, L. M. (Editor)

1973-01-01

Detailed data are presented on phenolic-glass and phenolic-asbestos compounds which compare the effect of compression molding without degas to the effects of four variations of compression molding. These variations were designed to improve elimination of entrapped volatiles and the volatile products of the condensate reaction associated with the cure of phenolic resins. The utilization of conventional methods of degas plus degas by vacuum and directional heat flow methods are involved. Detailed data are also presented on these same compounds, comparing the effect of changes in post-bake time, and post-bake temperature for the five molding techniques.

Quality and stability of edible oils enriched with hydrophilic antioxidants from the olive tree: the role of enrichment extracts and lipid composition.

PubMed

Sánchez de Medina, Verónica; Priego-Capote, Feliciano; Jiménez-Ot, Carlos; Luque de Castro, María Dolores

2011-11-09

Phenolic extracts from olive tree leaves and olive pomace were used to enrich refined oils (namely, maize, soy, high-oleic sunflower, sunflower, olive, and rapeseed oils) at two concentration levels (200 and 400 μg/mL, expressed as gallic acid). The concentration of characteristic olive phenols in these extracts together with the lipidic composition of the oils to be enriched influenced the mass transfer of the target antioxidants, which conferred additional stability and quality parameters to the oils as a result. In general, all of the oils experienced either a noticeable or dramatic improvement of their quality-stability parameters (e.g., peroxide index and Rancimat) as compared with their nonenriched counterparts. The enriched oils were also compared with extra virgin olive oil with a natural content in phenols of 400 μg/mL. The healthy properties of these phenols and the scarce or nil prices of the raw materials used can convert oils in supplemented foods or even nutraceuticals.

Modulation of the phenolic composition and colour of red wines subjected to accelerated ageing by controlling process variables.

PubMed

González-Sáiz, J M; Esteban-Díez, I; Rodríguez-Tecedor, S; Pérez-Del-Notario, N; Arenzana-Rámila, I; Pizarro, C

2014-12-15

The aim of the present work was to evaluate the effect of the main factors conditioning accelerated ageing processes (oxygen dose, chip dose, wood origin, toasting degree and maceration time) on the phenolic and chromatic profiles of red wines by using a multivariate strategy based on experimental design methodology. The results obtained revealed that the concentrations of monomeric anthocyanins and flavan-3-ols could be modified through the application of particular experimental conditions. This fact was particularly remarkable since changes in phenolic profile were closely linked to changes observed in chromatic parameters. The main strength of this study lies in the possibility of using its conclusions as a basis to make wines with specific colour properties based on quality criteria. To our knowledge, the influence of such a large number of alternative ageing parameters on wine phenolic composition and chromatic attributes has not been studied previously using a comprehensive experimental design methodology. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effect of Cooking on Isoflavones, Phenolic Acids, and Antioxidant Activity in Sprouts of Prosoy Soybean (Glycine max).

PubMed

Kumari, Shweta; Chang, Sam K C

2016-07-01

Soy sprouts possess health benefits and is required to be cooked before consumption. The effects of cooking on the phenolic components and antioxidant properties of soy sprouts with different germination days were investigated. A food-grade cultivar Prosoy with a high protein content was germinated for 1, 2, 3, 5, and 7 d and cooked till palatable for 20, 20, 5, 5, and 7 min, respectively. Total phenolic content (TPC), total flavonoids content (TFC), condensed tannins content (CTC), individual phenolic acids, isoflavones, DPPH, ferric-reducing antioxidant power (FRAP), and oxygen radical absorbance capacity (ORAC) of raw and cooked sprouts were measured. Cooking caused significant losses in phenolic content and antioxidant activities, and maximum loss was on day 3 > 5 > 7, including TPC (32%, 23%, and 15%), TFC (50%, 44%, and 20%), CTC (73%, 47%, and 12%), DPPH (31%, 15%, and 5%), FRAP (34%, 25%, and 1%), and ORAC (34%, 22%, 32%), respectively. Cooking caused significant losses in most individual phenolic acid, benzoic group, cinnamic group, total phenolic composition, individual isoflavones, and total isoflavones. The losses of phenolic acids such as gallic, protocatechuic, hydroxybenzoic, syringic, chlorogenic, or sinapic acids during cooking were not compensated by the increases in trihydroxybenzoic, vanillic or coumaric acids on certain days of germination. Cooking caused minimal changes in phenolic acid composition of day 1 and 2 sprouts compared to 3, 5, and 7 d sprouts. © 2016 Institute of Food Technologists®

Soil type-depending effect of paddy management: composition and distribution of soil organic matter

NASA Astrophysics Data System (ADS)

Urbanski, Livia; Kölbl, Angelika; Lehndorff, Eva; Houtermans, Miriam; Schad, Peter; Zhang, Gang-Lin; Rahayu Utami, Sri; Kögel-Knabner, Ingrid

2016-04-01

Paddy soil management is assumed to promote soil organic matter accumulation and specifically lignin caused by the resistance of the aromatic lignin structure against biodegradation under anaerobic conditions during inundation of paddy fields. The present study investigates the effect of paddy soil management on soil organic matter composition compared to agricultural soils which are not used for rice production (non-paddy soils). A variety of major soil types, were chosen in Indonesia (Java), including Alisol, Andosol and Vertisol sites (humid tropical climate of Java, Indonesia) and in China Alisol sites (humid subtropical climate, Nanjing). This soils are typically used for rice cultivation and represent a large range of soil properties to be expected in Asian paddy fields. All topsoils were analysed for their soil organic matter composition by solid-state 13C nuclear magnetic resonance spectroscopy and lignin-derived phenols by CuO oxidation method. The soil organic matter composition, revealed by solid-state 13C nuclear magnetic resonance, was similar for the above named different parent soil types (non-paddy soils) and was also not affected by the specific paddy soil management. The contribution of lignin-related carbon groups to total SOM was similar in the investigated paddy and non-paddy soils. A significant proportion of the total aromatic carbon in some paddy and non-paddy soils was attributed to the application of charcoal as a common management practise. The extraction of lignin-derived phenols revealed low VSC (vanillyl, syringyl, cinnamyl) values for all investigated soils, being typical for agricultural soils. An inherent accumulation of lignin-derived phenols due to paddy management was not found. Lignin-derived phenols seem to be soil type-dependent, shown by different VSC concentrations between the parent soil types. The specific paddy management only affects the lignin-derived phenols in Andosol-derived paddy soils which are characterized by significantly higher VSC values compared to their parent soil types. However, the higher organic carbon concentrations in Andosol and Alisol (China)-derived paddy soils compared to their parent soil types, could not be explained by an enrichment of lignin-derived phenols. It seems that site specific incorporation of crop residues and properties of the parent soil types are likely more important for organic carbon contents and soil organic matter composition than the effect of paddy management itself.

LC-MS analysis of phenolic compounds and antioxidant activity of buckwheat at different stages of malting.

PubMed

Terpinc, Petra; Cigić, Blaž; Polak, Tomaž; Hribar, Janez; Požrl, Tomaž

2016-11-01

The impact of malting on the profile of the phenolic compounds and the antioxidant properties of two buckwheat varieties was investigated. The highest relative increases in phenolic compounds were observed for isoorientin, orientin, and isovitexin, which are consequently major inducible phenolic compounds during malting. Only a minor relative increase was observed for the most abundant phenolic compound, rutin. The radical-scavenging activity of buckwheat seeds was evaluated using ABTS and DPPH assays. A considerable increase in total phenolic compounds and higher antioxidant activity were observed after 64h of germination, whereas kilning resulted in decreased total phenolic compounds and antioxidant activity. Higher antioxidant activities for extracts were found for buffered solvents than for pure methanol and water. Changes in the composition of the phenolic compounds and increased antioxidant content were confirmed by several methods, indicating that buckwheat malt can be used as a food rich in antioxidants. Copyright © 2016 Elsevier Ltd. All rights reserved.

Supercritical fluid extraction of grape seeds: extract chemical composition, antioxidant activity and inhibition of nitrite production in LPS-stimulated Raw 264.7 cells.

PubMed

Pérez, Concepción; Ruiz del Castillo, María Luisa; Gil, Carmen; Blanch, Gracia Patricia; Flores, Gema

2015-08-01

Grape by-products are a rich source of bioactive compounds having broad medicinal properties, but are usually wasted from juice/wine processing industries. The present study investigates the use of supercritical fluid extraction (SFE) for obtaining an extract rich in bioactive compounds. First, some variables involved in the extraction were applied. SFE conditions were selected based on the oil mass yield, fatty acid profile and total phenolic composition. As a result, 40 °C and 300 bar were selected as operational conditions. The phenolic composition of the grape seed oil was determined using LC-DAD. The antioxidant activity was determined by ABTS and DPPH assays. For the anti-inflammatory activity the inhibition of nitrite production was assessed. The grape seed oil extracted was rich in phenolic compounds and fatty acids with significant antioxidant and anti-inflammatory activities. From these results, added economic value to this agroindustrial residue is proposed using environmentally friendly techniques.

Optimization of aircraft interior panels

NASA Technical Reports Server (NTRS)

Kourtides, Demetrius A.; Roper, Willard D.

1986-01-01

Eight different graphite composite panels were fabricated using four different resin matrices. The resin matrices included Hercules 71775, a blend of vinylpolystyrpyridine and bismaleimide, H795, a bismaleimide, Cycom 6162, a phenolic, and PSP 6022M, a polystyrylpyridine. Graphite panels were fabricated using fabric or unidirectional tape. This report describes the processes for preparing these panels and some of their mechanical, thermal and flammability properties. Panel properties are compared with state-of-the-art epoxy fiberglass composite panels.

Review of thermal properties of graphite composite materials

NASA Technical Reports Server (NTRS)

Kourtides, D. A.

1987-01-01

Flammability, thermal, and selected mechanical properties of composites fabricated with epoxy and other thermally stable resin matrices are described. Properties which were measured included limiting-oxygen index, smoke evolution, thermal degradation products, total-heat release, heat-release rates, mass loss, flame spread, ignition resistance, thermogravimetric analysis, and selected mechanical properties. The properties of 8 different graphite composite panels fabricated using four different resin matrices and two types of graphite reinforcement are described. The resin matrices included: XU71775/H795, a blend of vinyl polystyryl pyridine and bismaleimide; H795, a bismaleimide; Cycom 6162, a phenolic; and PSP 6022M, a polystyryl pyridine. The graphite fiber used was AS-4 in the form of either tape or fabric. The properties of these composites were compared with epoxy composites. It was determined that the blend of vinyl polystyryl pyridine and bismaleimide (XU71775/H795) with the graphite tape was the optimum design giving the lowest heat release rate.

Antioxidant and Anti-tyrosinase Activities of Phenolic Extracts from Rape Bee Pollen and Inhibitory Melanogenesis by cAMP/MITF/TYR Pathway in B16 Mouse Melanoma Cells.

PubMed

Sun, Liping; Guo, Yan; Zhang, Yanxin; Zhuang, Yongliang

2017-01-01

Rape bee pollen possesses many nutritional and therapeutic properties because of its abundant nutrimental and bioactive components. In this study, free (FPE) and bound (BPE) phenolic extracts of rape bee pollen were obtained, phenolic and flavonoid contents were determined, and composition of phenolic acids was analyzed. In vitro antioxidant and anti-tyrosinase (TYR) activities of FPE and BPE were compared, and inhibitory melanogenesis of FPE was further evaluated. Results showed FPE and BPE contain total phenolic contents of 11.76 and 0.81 mg gallic acid equivalents/g dry weight (DW) and total flavonoid contents of 19.24 and 3.65 mg rutin equivalents/g DW, respectively. Phenolic profiling showed FPE and BPE fractions contained 12 and 9 phenolic acids, respectively. FPE contained the highest rutin content of 774.87 μg/g. FPE and BPE showed the high antioxidant properties in vitro and high inhibitory activities for mushroom TYR. Higher activities of FPE than those of BPE can be attributed to difference in their phenolic compositions. Inhibitory melanogenesis activities of FPE against B16 were further evaluated. Results showed suppressed intracellular TYR activity, reduced melanin content, and promoted glutathione synthesis ( p < 0.05) in FPE-treated cells. FPE reduced mRNA expression of TYR, TYR-related protein (TRP)-1 and TRP-2, and significantly suppressed cyclic adenosine monophosphate (cAMP) levels through down-regulation of melanocortin 1 receptor gene expression ( p < 0.05). FPE reduced mRNA expression of microphthalmia-associated transcription factor (MITF), significantly inhibiting intracellular melanin synthesis ( p < 0.05). Hence, FPE regulates melanogenesis of B16 cells involved in cAMP/MITF/TYR pathway. These results revealed that FPE can be used as pharmaceutical agents and cosmetics to protect cells from abnormal melanogenesis.

Chemical composition and bioactive compounds of garlic (Allium sativum L.) as affected by pre- and post-harvest conditions: A review.

PubMed

Martins, Natália; Petropoulos, Spyridon; Ferreira, Isabel C F R

2016-11-15

Garlic (Allium sativum L.) is considered one of the twenty most important vegetables, with various uses throughout the world, either as a raw vegetable for culinary purposes, or as an ingredient of traditional and modern medicine. Furthermore, it has also been proposed as one of the richest sources of total phenolic compounds, among the usually consumed vegetables, and has been highly ranked regarding its contribution of phenolic compounds to human diet. This review aims to examine all the aspects related with garlic chemical composition and quality, focusing on its bioactive properties. A particular emphasis is given on the organosulfur compounds content, since they highly contribute to the effective bioactive properties of garlic, including its derived products. The important effects of pre-harvest (genotype and various cultivation practices) and post-harvest conditions (storage conditions and processing treatments) on chemical composition and, consequently, bioactive potency of garlic are also discussed. Copyright © 2016 Elsevier Ltd. All rights reserved.

Study of the chemical composition of the resinous exudate isolated from Heliotropium sclerocarpum and evaluation of the antioxidant properties of the phenolic compounds and the resin.

PubMed

Modak, Brenda; Salina, Melissa; Rodilla, Jesús; Torres, René

2009-11-12

Heliotropium sclerocarpum Phil. (Heliotropiaceae) is a resinous bush that grows in the Atacama of northern Chile. The chemical composition of its resinous exudate was analyzed for the first time. One aromatic geranyl derivative: filifolinol (1), one flavanone: naringenin (2) and a new type of 3-oxo-2-arylbenzofuran derivative 3 were isolated and their structures were determined. The antioxidant activity of the phenolic compounds and resin was evaluated using the bleaching of DPPH radical method and expressed as fast reacting equivalents (FRE) and total reacting equivalents (TRE).

Development of Refined Natural Resin based Cashew Nut Shell Oil Liquid (CNSL) for Brake Pads Composite

NASA Astrophysics Data System (ADS)

Wahyuningsih, S.; Ramelan, A. H.; Rahmawati, P.; Tamtama, B. P. N.; Sari, P. P.; Sari, P. L.; Ichsan, S.; Kristiawan, Y. R.; Aini, F. N.

2017-02-01

Brake is one of the most important components in the vehicle. One type of brake that widely used is brake-based composites. One of the manufacture of composite material is resin. Cashew Nut Shell Liquid (CNSL) is a natural material which has chemical structure similar to synthetic phenol so it can be an alternative as a resin. Brake pads manufacture using CNSL as resin composites made to obtain the brake which is strong, wear-resistant, and environmentally friendly. The composite made using powder metallurgy techniques by mixing ingredients such as rubber, fibre glass, carbon, mineral sands and phenolic resin. Two formulas were composed by varying the resin and iron mineral sands in 5 grams. Composites were tested using Universal Testing Machine (UTM). The tensile strength result of those formulas are 600 N and 900 N and the elongations are 1.98 mm and 2.59 mm respectively. Formula 2 has a better tensile strength due to the addition of more resin is 15%. Since the better properties, formula 2 was derivated to 4 extended formulas and showed excellent pressure strength reached 20.000 N. It indicates that the addition of the resin can improve the mechanical properties of a composite.

Distribution of phenolic antioxidants in whole and milled fractions of quinoa and their inhibitory effects on α-amylase and α-glucosidase activities.

PubMed

Hemalatha, P; Bomzan, Dikki Pedenla; Sathyendra Rao, B V; Sreerama, Yadahally N

2016-05-15

Whole grain quinoa and its milled fractions were evaluated for their phenolic composition in relation to their antioxidant properties and inhibitory effects on α-amylase and α-glucosidase activities. Compositional analysis by HPLC-DAD showed that the distribution of phenolic compounds in quinoa is not entirely localised in the outer layers of the kernel. Milling of whole grain quinoa resulted in about 30% loss of total phenolic content in milled grain. Ferulic and vanillic acids were the principal phenolic acids and rutin and quercetin were predominant flavonoids detected in whole grain and milled fractions. Quinoa milled fractions exhibited numerous antioxidant activities. Despite having relatively lower phenolic contents, dehulled and milled grain fractions showed significantly (p ⩽ 0.05) higher metal chelating activity than other fractions. Furthermore, extracts of bran and hull fractions displayed strong inhibition towards α-amylase [IC50, 108.68 μg/ml (bran) and 148.23 μg/ml (hulls)] and α-glucosidase [IC50, 62.1 μg/ml (bran) and 68.14 μg/ml (hulls)] activities. Thus, whole grain quinoa and its milled fractions may serve as functional food ingredients in gluten-free foods for promoting health. Copyright © 2015 Elsevier Ltd. All rights reserved.

Polymeric materials from renewable resources

NASA Astrophysics Data System (ADS)

Frollini, Elisabete; Rodrigues, Bruno V. M.; da Silva, Cristina G.; Castro, Daniele O.; Ramires, Elaine C.; de Oliveira, Fernando; Santos, Rachel P. O.

2016-05-01

The goals of our studies have been the use of renewable raw materials in the preparation of polymeric materials with diversified properties. In this context, lignosulfonate, which is produced in large scale around the world, but not widely used in the production of polymeric materials, was used to replace phenol and polyols in the preparation of phenolic- (Ligno-PH) and polyurethane-type (Ligno-PU) polymers, respectively. These polymers were used to prepare composites reinforced with sisal lignocellulosic fibers. The use of lignosulfonate in the formulation of both types of polymers was beneficial, because in general composites with improved properties, specially impact strength, were obtained. Composites were also prepared from the so called "biopolyethylene" (HDPE), curaua lignocellulosic fiber, and castor oil (CO). All composites HDBPE/CO/Fiber exhibited higher impact strength, when compared to those of the corresponding HDBPE/Fiber. These results, combined with others (eg SEM images of the fractured surfaces) indicated that, in addition to acting as a plasticizer, this oil may have acted as a compatibilizer of the hydrophilic fiber with the hydrophobic polymer. The set of results indicated that (i) mats with nano (diameter ≤ 100nm) and/or ultrafine (submicron scale) fibers were produced, (ii) hybrid fibers were produced (bio-based mats composites), (iii) cellulosic pulp (CP) and/or lignin (Lig) can be combined with PET matrices to control properties such as stiffness and hydrophilicity of the respective mats. Materials with diversified properties were prepared from high content of renewable raw materials, thus fulfilling the proposed targets.

Phenolic Compounds in the Potato and Its Byproducts: An Overview

PubMed Central

Akyol, Hazal; Riciputi, Ylenia; Capanoglu, Esra; Caboni, Maria Fiorenza; Verardo, Vito

2016-01-01

The potato (Solanum tuberosum L.) is a tuber that is largely used for food and is a source of different bioactive compounds such as starch, dietary fiber, amino acids, minerals, vitamins, and phenolic compounds. Phenolic compounds are synthetized by the potato plant as a protection response from bacteria, fungi, viruses, and insects. Several works showed that these potato compounds exhibited health-promoting effects in humans. However, the use of the potato in the food industry submits this vegetable to different processes that can alter the phenolic content. Moreover, many of these compounds with high bioactivity are located in the potato’s skin, and so are eliminated as waste. In this review the most recent articles dealing with phenolic compounds in the potato and potato byproducts, along with the effects of harvesting, post-harvest, and technological processes, have been reviewed. Briefly, the phenolic composition, main extraction, and determination methods have been described. In addition, the “alternative” food uses and healthy properties of potato phenolic compounds have been addressed. PMID:27240356

Antiradical capacity and polyphenol composition of asparagus spears varieties cultivated under different sunlight conditions.

PubMed

Kulczyński, Bartosz; Kobus-Cisowska, Joanna; Kmiecik, Dominik; Gramza-Michałowska, Anna; Golczak, Dorota; Korczak, Józef

2016-01-01

Asparagus officinalis has a high nutritional value. Asparagus is rich in a number of bioactive compounds, mainly flavonoids (quercetin), glutathione, vitamin C, vitamin E, fructans (inulin and fructooligosaccharides) and phytosterols (b-sitosterol). These compounds may play an important role in human health. The purpose of this study was to examine the antioxidant potential and polyphenol composition of white, pale-colored and green asparagus spears of different cultivars. Investigations were conducted on different asparagus spear extracts. The study included three colors of asparagus (white, pale-colored and green) from five different cultivars subjected to the ethanol extraction procedure. Total phenolic content was also determined by the Folin-Ciocalteu method. Polyphenol (phenolic acids and flavonols) composition was estimated using the HPLC method. The antioxidant properties of extracts were examined using DPPH, ABTS and metal ion chelating assays. The highest contents of phenolic and flavonoids were observed in green asparagus from Grolim and the lowest in pale-colored asparagus from Gyjmlin. It was found that both the color of asparagus and the cultivar had a significant effect on the composition of phenolic acid and flavonols. Radical scavenging activity toward DPPH• and ABTS was highest for green asparagus cv. Grolim and Eposs. The greatest number of Fe ions was chelated by samples of green asparagus cv. Grolim and Huchel's Alpha and pale-colored asparagus cv. Huchel's Alpha. It was shown that the antioxidant activity of asparagus spears measured by antiradical and chelating activity test depends on variety and color. The highest activity was found in green asparagus and the lowest was identified in white asparagus extracts. It has also been clarified that changes in flavonol and phenolic acid composition and increases in their diversity depends on growing with sunlight and variety. Asparagus can provide a valuable source of phenolic compounds in the human diet.

Supercritical-assistant liquid crystal template approach to synthesize mesoporous titania/multiwalled carbon nanotube composites with high visible-light driven photocatalytic performance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Chen; Li, Youji, E-mail: bcclyj@163.com; Xu, Peng

2014-12-15

Graphical abstract: We investigate the influence of mesoporous titania content upon the visible-light driven photocatalytic performance of MPT/MWCNTs in phenol degradation. - Highlights: • MPT/MWCNTs were fabricated by liquid-crystal template in supercritical CO{sub 2}. • MPT/MWCNTs show high visible-light driven photoactivity for phenol degradation. • MPT/MWCNTs also show high reusable photoactivity under visible irradiation. • MPT content can control visible-light driven photoactivity of MPT/MWCNTs. • MPT is not easily broken away from from MPT/MWCNT composites. - Abstract: Mesoporous titania (MPT) was deposited onto multiwalled carbon nanotubes (MWCNTs) by deposition of titanium sol containing liquid-crystal template with assistant of supercritical CO{submore » 2}. The products were characterized with various analytical techniques to determine their structural, morphological, optical absorption and photocatalytic properties. The results indicate that in photocatalytic degradation of phenol under visible light, the mixtures or composites of MPT and MWCNT show the high efficiency because of synergies between absorbing visible light, releasing electrons and facilitating transfer of charge carriers of MWCNTs and providing activated centers of MPT. Because of the mutual constraint between MPT and MWCNTs on the photocatalytic efficiency, the optimal loading of MPT in MPT/MWCNT-3 for phenol degradation is 48%. Because the intimate contact between MWCNTs and MPT is more beneficial to electron transformation, photoactivity of mixture is lower than that of composites with high reusable performance. The optimum conditions of phenol degradation were obtained.« less

Nutraceutical composition of Zizyphus mauritiana Lamk (Indian ber): effect of enzyme-assisted processing.

PubMed

Koley, Tanmay Kumar; Walia, Shweta; Nath, Prerna; Awasthi, O P; Kaur, Charanjit

2011-05-01

Zizyphus (Indian ber) is an excellent source of several phenolic compounds. The effect of two cell wall degrading enzymes, namely pectinase and viscozyme, on the nutraceutical composition of Zizyphus juice was investigated in the present study. Enzyme assisted processing significantly (P < 0.05) improved the juice yield, total soluble solids, total phenolics and total antioxidant activity (AOX). There was significant increase in recovery of antioxidants, to the tune of 70.51%, 66%, and 45% respectively in ascorbic acid, total phenolics and total flavonoids through viscozyme. The in-vitro total AOX of juice extracted via enzyme-assisted processing was 20.9 and 15.59 μmol Trolox/ml in ferric-reducing antioxidant power and cupric-reducing antioxidant capacity assays, respectively. There was 41% increase in AOX of juice extracted with enzyme over straight pressed juice. Results indicate that enzyme-assisted processing can significantly improve the functional properties of the Zizyphus juice.

Sulfur free red wines through the use of grapevine shoots: Impact on the wine quality.

PubMed

Raposo, Rafaela; Chinnici, Fabio; Ruiz-Moreno, María José; Puertas, Belén; Cuevas, Francisco J; Carbú, María; Guerrero, Raúl F; Ortíz-Somovilla, Víctor; Moreno-Rojas, José Manuel; Cantos-Villar, Emma

2018-03-15

Following a preliminary study to determine the possibility of using a grapevine shoot extract (VIN) as a sustainable alternative to sulfur dioxide (SO 2 ), in this study, the chromatic features, phenolic composition, and sensory analysis of wines treated with VIN at two concentrations were studied during storage in bottle for the first time. The highest differences were found in phenolic compounds after 12months of storage in bottle. The VIN wines had a low content of free anthocyanins and were high in vinyl-pyranoanthocyanins, and B-type vitisins. Consequently, they showed better chromatic characteristics. Moreover VIN, especially at high dose, preserved non-anthocyanin phenolic compounds better than SO 2 . However, at this high dose some organoleptic properties were affected. VIN, when used at a low dose, is able to preserve wine composition without loss of quality. Copyright © 2017 Elsevier Ltd. All rights reserved.

Pilot-scale resin adsorption as a means to recover and fractionate apple polyphenols.

PubMed

Kammerer, Dietmar R; Carle, Reinhold; Stanley, Roger A; Saleh, Zaid S

2010-06-09

The purification and fractionation of phenolic compounds from crude plant extracts using a food-grade acrylic adsorbent were studied at pilot-plant scale. A diluted apple juice concentrate served as a model phenolic solution for column adsorption and desorption trials. Phenolic concentrations were evaluated photometrically using the Folin-Ciocalteu assay and by HPLC-DAD. Recovery rates were significantly affected by increasing phenolic concentrations of the feed solutions applied to the column. In contrast, the flow rate during column loading hardly influenced adsorption efficiency, whereas the temperature and pH value were shown to be crucial parameters determining both total phenolic recovery rates and the adsorption behavior of individual polyphenols. As expected, the eluent composition had the greatest impact on the desorption characteristics of both total and individual phenolic compounds. HPLC analyses revealed significantly different elution profiles of individual polyphenols depending on lipophilicity. This technique allows fractionation of crude plant phenolic extracts, thus providing the opportunity to design the functional properties of the resulting phenolic fractions selectively, and the present study delivers valuable information with regard to the adjustment of individual process parameters.

Gluten-Free Precooked Rice-Yellow Pea Pasta: Effect of Extrusion-Cooking Conditions on Phenolic Acids Composition, Selected Properties and Microstructure.

PubMed

Bouasla, Abdallah; Wójtowicz, Agnieszka; Zidoune, Mohammed Nasereddine; Olech, Marta; Nowak, Renata; Mitrus, Marcin; Oniszczuk, Anna

2016-05-01

Rice/yellow pea flour blend (2/1 ratio) was used to produce gluten-free precooked pasta using a single-screw modified extrusion-cooker TS-45. The effect of moisture content (28%, 30%, and 32%) and screw speed (60, 80, and 100 rpm) on some quality parameters was assessed. The phenolic acids profile and selected pasta properties were tested, like pasting properties, water absorption capacity, cooking loss, texture characteristics, microstructure, and sensory overall acceptability. Results indicated that dough moisture content influenced all tested quality parameters of precooked pasta except firmness. Screw speed showed an effect only on some quality parameters. The extrusion-cooking process at 30% of dough moisture with 80 rpm is appropriate to obtain rice-yellow pea precooked pasta with high content of phenolics and adequate quality. These pasta products exhibited firm texture, low stickiness, and regular and compact interne structure confirmed by high score in sensory overall acceptability. © 2016 Institute of Food Technologists®

Magnetically separable maghemite/montmorillonite composite as an efficient heterogeneous Fenton-like catalyst for phenol degradation.

PubMed

Jin, Mingjie; Long, Mingce; Su, Hanrui; Pan, Yue; Zhang, Qiuzhuo; Wang, Juan; Zhou, Baoxue; Zhang, Yanwu

2017-01-01

To develop highly efficient and conveniently separable iron containing catalysts is crucial to remove recalcitrant organic pollutants in wastewater through a heterogeneous Fenton-like reaction. A maghemite/montmorillonite composite was synthesized by a coprecipitation and calcination method. The physiochemical properties of catalysts were characterized by XRD, TEM, nitrogen physisorption, thermogravimetric analysis/differential scanning calorimetry (TG/DSC), zeta potential, and magnetite susceptibility measurements. The influence of calcination temperatures and reaction parameters was investigated. The calcined composites retain magnetism because the presence of montmorillonite inhibited the growth of γ-Fe 2 O 3 nanoparticles, as well as their phase transition. The catalytic activities for phenol degradation were significantly enhanced by calcinations, which strengthen the interaction between iron oxides and aluminosilicate framework and result in more negatively charged surface. The composite (73 m 2 /g) calcined at 350 °C had the highest catalytic activities, with more than 99 % phenol reduction after only 35 min reaction at pH 3.6. Simultaneously, this catalyst exhibited high stability, low iron leaching, and magnetically separable ability for consecutive usage, making it promising for the removal of recalcitrant organic pollutants in wastewater.

Electrochemical Properties of Graphene Oxide/Resol Composites as Electrode Materials for Supercapacitor Applications.

PubMed

Park, Geon Woo; Jeon, Sang Kwon; Yang, Jin Yong; Choi, Sung Dae; Kim, Geon Joong

2016-05-01

RGO/Resol carbon composites were prepared from a mixture of reduced GO and a low-molecular-weight phenolic resin (Resol) solution. The effects of the calcination temperature, amount of Resol added and KOH treatment on the electrochemical performance of the RGO/Resol composites were investigated. The physical and electrochemical properties of the composite materials were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Brunauer, Emmett and Teller (BET) surface areas measurements, and cyclic voltammetry (CV). The relationships between their physical properties and their electrochemical performance were examined for use as super-capacitors (SCs). The RGO/Resol composite calcined at 400 degrees C after the KOH loading showed dramatically improved electrochemical properties, showing a high BET surface and capacitance of 2190 m2/g and 220 F/g, respectively. The RGO/Resol composites calcined after the KOH treatment showed much better capacitor performance than those treated only thermally at the same temperature without KOH impregnation. The fabrication of high surface electrodes was essential for improving the SCs properties.

Phenol adsorption by activated carbon produced from spent coffee grounds.

PubMed

Castro, Cínthia S; Abreu, Anelise L; Silva, Carmen L T; Guerreiro, Mário C

2011-01-01

The present work highlights the preparation of activated carbons (ACs) using spent coffee grounds, an agricultural residue, as carbon precursor and two different activating agents: water vapor (ACW) and K(2)CO(3) (ACK). These ACs presented the microporous nature and high surface area (620-950 m(2) g(-1)). The carbons, as well as a commercial activated carbon (CAC) used as reference, were evaluated as phenol adsorbent showing high adsorption capacity (≈150 mg g(-1)). The investigation of the pH solution in the phenol adsorption was also performed. The different activating agents led to AC with distinct morphological properties, surface area and chemical composition, although similar phenol adsorption capacity was verified for both prepared carbons. The production of activated carbons from spent coffee grounds resulted in promising adsorbents for phenol removal while giving a noble destination to the residue.

Standardization of the carbon-phenolic materials and processes. Vol. 1: Experimental studies

NASA Technical Reports Server (NTRS)

Hall, William B.

1988-01-01

Carbon-phenolic composite materials are used as ablative material in the solid rocket motor nozzle of the Space Shuttle. The nozzle is lined with carbon cloth-phenolic resin composites. The nominal effects of the completely consumed solid propellant on the carbon-phenolic material are given. The extreme heat and erosion of the burning propellant are controlled by the carbon-phenolic composite by ablation, the heat and mass transfer process in which a large amount of heat is absorbed by sacrificially removing material from the nozzle surface. Phenolic materials ablate with the initial formation of a char. The depth of the char is a function of the heat conduction coefficient of the composite. The char layer is a very poor heat conductor so it protects the underlying phenolic composite from the high heat of the burning propellant. The nozzle component ablative liners (carbon cloth-phenolic composites) are tape wrapped, hydroclave and/or autoclave cured, machined, and assembled. The tape consists of a prepreg broadcloth. The materials flow sheet for the nozzle ablative liners is shown. The prepreg is a three component system: phenolic resin, carbon cloth, and carbon filler. This is Volume 1 of two, Experimental Studies.

Standardization of the carbon-phenolic materials and processes. Vol. 2: Test methods and specifications

NASA Technical Reports Server (NTRS)

Hall, William B.

1988-01-01

Carbon-phenolic composite materials are used in the ablation process in the nozzles of the Space Shuttle Main Engine. The nozzle is lined with carbon cloth-phenolic resin composites. The extreme heat and erosion of the burning propellant are controlled by the carbon-phenolic composite by means of ablation, a heat and mass transfer process in which a large amount of heat is dissipated by sacrificailly removing material from a surface. Phenolic materials ablate with the initial formation of a char. The depth of the char is a function of the heat conduction coefficient of the composite. The char layer is a poor conductor so it protects the underlying phenolic composite from the high heat of the burning propellant. The nozzle component ablative liners (carbon cloth-phenolic resin composites) are tape wrapped, hydroclave and/or autoclave cured, machined and assembled. The tape consists of prepreg broadcloth. The materials flow sheet for the nozzle ablative liners is given. The prepreg is a three component system: phenolic resin, carbon cloth, and carbon filler. This is Volume 2 of the report, Test Methods and Specifications.

Equilibrated moisture content of several carbon phenolics and their relationship to resin, fiber, and interface properties

NASA Technical Reports Server (NTRS)

Stokes, E. H.

1991-01-01

This study focuses on the relationship between relative humidity and the equilibrated moisture content of several variants of two distinctly different carbon phenolic composites. One of the materials gives a typical exponential relationship between RH and equilibrated moisture content while the second gives an inverse sigmoidal relationship with the largest increase in moisture between 45-60 percent relative humidity. The possible relationship between the shape of the curves and the nature of the material constituents is discussed.

Chicken feather fiber as an additive in MDF composites

Treesearch

Jerrold E. Winandy; James H. Muehl; Jessie A. Glaeser; Walter Schmidt

2007-01-01

Medium density fiberboard (MDF) panels were made with aspen fiber and 0-95% chicken feather fiber (CFF) in 2.5%, 5%, or 25% increments, using 5% phenol formaldehyde resin as the adhesive. Panels were tested for mechanical and physical properties as well as decay. The addition of CFF decreased strength and stiffness of MDF-CFF composites compared with that of all-wood...

Silicone Polymer Composites for Thermal Protection System: Fiber Reinforcements and Microstructures

DTIC Science & Technology

2010-01-01

angles were tested. Detailed microstructural, mass loss, and peak erosion analyses were conducted on the phenolic -based matrix composite (control) and...silicone-based matrix composites to understand their protective mechanisms. Keywords silicone polymer matrix composites, phenolic polymer matrix...erosion analyses were conducted on the phenolic -based matrix composite (control) and silicone-based matrix composites to understand their protective

Study of the mechanical properties of hybrid composite basalt / alumina / shells for brake lining pads

NASA Astrophysics Data System (ADS)

Adi Atmika, I. K.; Ary Subagia, IDG.; Surata, I. W.; Sutantra, I. N.

2017-05-01

Brake lining pad as one of the active safety components in motor vehicles has been studied thoroughly. Asbestos is the main material forming the brake in addition to other alloy materials that have a negative impact on health and the environment. This paper explain the behavior of hybrid composites phenolic resin with basalt/alumina/clamshell powder reinforced on brake lining pad. This materials has been manufactured use compaction and sintering process through any steps, that an emphasis of 2,000 kg for 30 minutes at a constant temperature of 150° C. The research aims to investigate hardness characteristic of hybrid composite that test using the vickers according to standard ASTM E-384. The reinforced materials and phenolic resin composition is 60%: 40%. The results show for the average hardness VHN to 24.18, 25.11, 26.34, 27.21 and 28.83. The average hardness hybrid composite shows the hardness harder than asbestos materials.

Phenolic composition and antioxidant capacity of pomaces from four grape varieties (Vitis vinifera L.).

PubMed

de la Cerda-Carrasco, Aarón; López-Solís, Remigio; Nuñez-Kalasic, Hugo; Peña-Neira, Álvaro; Obreque-Slier, Elías

2015-05-01

Phenolic compounds are widely distributed secondary metabolites in plants usually conferring them with unique taste, flavour and health-promoting properties. In fruits of Vitis vinifera L., phenolic composition is highly dependent on grape variety. Differential extraction of these compounds from grapes during winemaking is critically associated with wine quality. By-products of winemaking, such as grape pomace, can contain significant amounts of polyphenols. However, information concerning the varietal effect on wine grape pomace is scarce. In this study, pomaces from Sauvignon Blanc (SB), Chardonnay (CH), Cabernet Sauvignon (CS) and Carménère (CA) grape varieties were characterized spectroscopically and by HPLC-DAD analysis. White grape pomaces (SB and CH) presented higher antioxidant capacities and higher contents of total phenols and total proanthocyanidins compared with red grape pomaces (CS and CA), whereas the latter showed much higher anthocyanin levels and colour intensities. Concentrations of monomeric proanthocyanidins and low-molecular-weight phenols in the four grape pomace varieties were significantly different. Grape pomaces from four varieties showed high but diverse contents of polyphenols and antioxidant capacities. Thus grape pomaces represent an important potential source of polyphenols, which could be useful for nutritional and/or pharmacological purposes. © 2014 Society of Chemical Industry.

Phenolic Composition and Evaluation of the Antimicrobial Activity of Free and Bound Phenolic Fractions from a Peruvian Purple Corn (Zea mays L.) Accession.

PubMed

Gálvez Ranilla, Lena; Christopher, Ashish; Sarkar, Dipayan; Shetty, Kalidas; Chirinos, Rosana; Campos, David

2017-12-01

Beneficial effects on overall gut health by phenolic bioactives-rich foods are potentially due to their modulation of probiotic gut bacteria and antimicrobial activity against pathogenic bacteria. Based on this rationale, the effect of the free and bound phenolic fractions from a Peruvian purple corn accession AREQ-084 on probiotic lactic acid bacteria such as Lactobacillus helveticus and Bifidobacterium longum and the gastric cancer-related pathogen Helicobacter pylori was evaluated. The free and bound phenolic composition was also determined by ultra-performance liquid chromatography. Anthocyanins were the major phenolic compounds (310.04 mg cyanidin-3-glucoside equivalents/100 g dry weight, DW) in the free phenolic fraction along with hydroxycinnamic acids such as p-coumaric acid derivatives, followed by caffeic and ferulic acid derivatives. The bound phenolic form had only hydroxycinnamic acids such as ferulic acid, p-coumaric acid, and a ferulic acid derivative with ferulic acid being the major phenolic compound (156.30 mg/100 g DW). These phenolic compounds were compatible with beneficial probiotic lactic acid bacteria such as L. helveticus and B. longum as these bacteria were not inhibited by the free and bound phenolic fractions at 10 to 50 mg/mL and 10 mg/mL of sample doses, respectively. However, the pathogenic H. pylori was also not inhibited by both purple corn phenolic forms at same above sample doses. This study provides the preliminary base for the characterization of phenolic compounds of Peruvian purple corn biodiversity and its potential health benefits relevant to improving human gut health. This study provides insights that Peruvian purple corn accession AREQ-084 can be targeted as a potential source of health-relevant phenolic compounds such as anthocyanins along with hydroxycinnamic acids linked to its dietary fiber fraction. Additionally, these phenolic fractions did not affect the gut health associated beneficial bacteria nor the pathogenic H. pylori. Purple corn can be targeted for design of probiotic functional foods integrated with their anthocyanin linked-coloring properties. © 2017 Institute of Food Technologists®.

Comparison of the Composition and Antioxidant Activities of Phenolics from the Fruiting Bodies of Cultivated Asian Culinary-Medicinal Mushrooms.

PubMed

Lin, Shaoling; Ching, Lai Tsz; Ke, Xinxin; Cheung, Peter Chi Keung

2016-01-01

The composition profile and the antioxidant properties of phenolics in water extracts obtained from the fresh fruiting bodies of 4 common cultivated Asian edible mushrooms-Agrocybe aegerita, Pleurotus ostreatus, P. eryngii, and Pholiota nameko were compared. The water extract from A. aegerita (AaE) had the highest total phenolic content (TPC) at 54.18 ± 0.27 gallic acid equivalents (μmol/L)/mg extract (P < 0.05), as measured by the Folin-Ciocalteu method, and consisted of the largest number (including gallic acid, protocatechuic acid, chlorogenic acid, ferulic acid, and sinapic acid) and total amounts of phenolic acids identified by Fourier transform-ion cyclotron resonance mass spectrometry. The water extract of Ph. nameko was found to have the second-highest TPC (43.55 ± 0.10 gallic acid equivalents [μmol/L]/mg extract), followed by the water extract of P. eryngii and the water extract of P. ostreatus (39.55 ± 0.25 and 39.02 ± 0.30 gallic acid equivalents/mg extract, respectively). The scavenging activities of the water extracts from these mushrooms were evaluated against 2,2-diphenyl-l-(2,4,6-trinitrophenyl) hydrazyl diphenylpicrylhydrazyl (DPPH), superoxide anion radicals, hydroxyl radicals, and hydrogen peroxide. Based on halfmaximal effective concentrations, AaE was more effective in scavenging hydrogen peroxide (<0.05), followed by DPPH (0.51 mg/mL), superoxide anion radicals (0.85 mg/mL) and hydroxyl radicals (5.94 mg/mL), then the other mushroom water extracts. The differences in the half-maximal effective concentrations of individual mushroom water extracts were probably the result of the different numbers and amounts of individual phenolic acids in the extracts. The antioxidant activities of the mushroom water extracts were correlated with their TPC. The strongest antioxidant properties of AaE were consistent with its highest TPC and with the largest number and amount of phenolics identified in the extract. These results indicated that cultivated edible mushrooms could be a potential source of natural antioxidants with free radical scavenging properties for application as a functional food ingredient.

Phenolic Compounds of Potato Peel Extracts: Their Antioxidant Activity and Protection against Human Enteric Viruses.

PubMed

Silva-BeltrÁn, Norma Patricia; Chaidez-Quiroz, Cristóbal; López-Cuevas, Osvaldo; Ruiz-Cruz, Saul; López-Mata, Marco A; Del-Toro-SÁnchez, Carmen Lizette; Marquez-Rios, Enrique; Ornelas-Paz, José de Jesús

2017-02-28

Potato peels (PP) contain several bioactive compounds. These compounds are known to provide human health benefits, including antioxidant and antimicrobial properties. In addition, these compounds could have effects on human enteric viruses that have not yet been reported. The objective of the present study was to evaluate the phenolic composition, antioxidant properties in the acidified ethanol extract (AEE) and water extract of PP, and the antiviral effects on the inhibition of Av-05 and MS2 bacteriophages, which were used as human enteric viral surrogates. The AEE showed the highest phenolic content and antioxidant activity. Chlorogenic and caffeic acids were the major phenolic acids. In vitro analysis indicated that PP had a strong antioxidant activity. A 3 h incubation with AEE at a concentration of 5 mg/ml was needed to reduce the PFU/ml (plaque-forming unit per unit volume) of Av-05 and MS2 by 2.8 and 3.9 log₁₀, respectively, in a dose-dependent manner. Our data suggest that PP has potential to be a source of natural antioxidants against enteric viruses.

Experimental Investigation on the Specific Heat of Carbonized Phenolic Resin-Based Ablative Materials

NASA Astrophysics Data System (ADS)

Zhao, Te; Ye, Hong; Zhang, Lisong; Cai, Qilin

2017-10-01

As typical phenolic resin-based ablative materials, the high silica/phenolic and carbon/phenolic composites are widely used in aerospace field. The specific heat of the carbonized ablators after ablation is an important thermophysical parameter in the process of heat transfer, but it is rarely reported. In this investigation, the carbonized samples of the high silica/phenolic and carbon/phenolic were obtained through carbonization experiments, and the specific heat of the carbonized samples was determined by a 3D DSC from 150 °C to 970 °C. Structural and compositional characterizations were performed to determine the mass fractions of the fiber and the carbonized product of phenolic which are the two constituents of the carbonized samples, while the specific heat of each constituent was also measured by 3D DSC. The masses of the carbonized samples were reduced when heated to a high temperature in the specific heat measurements, due to the thermal degradation of the carbonized product of phenolic resin in the carbonized samples. The raw experimental specific heat of the two carbonized samples and the carbonized product of phenolic resin was modified according to the quality changes of the carbonized samples presented by TGA results. Based on the mass fraction and the specific heat of each constituent, a weighted average method was adopted to obtain the calculated results of the carbonized samples. Due to the unconsolidated property of the fiber samples which impacts the reliability of the DSC measurement, there is a certain deviation between the experimental and calculated results of the carbonized samples. Considering the similarity of composition and structure, the data of quartz glass and graphite were used to substitute the specific heat of the high silica fiber and carbon fiber, respectively, resulting in better agreements with the experimental ones. Furthermore, the accurate specific heat of the high silica fiber and carbon fiber bundles was obtained by inversion, enabling the prediction of the specific heat of the carbonized ablators with different constituent mass fractions by means of the weighted average method in engineering.

Morphology and properties of wood-fiber reinforced blends of recycled polystyrene and polyethylene

Treesearch

John Simonsen; Timothy G. Rials

1996-01-01

Material properties of composites produced from recycled plastics and recycled wood fiber were compared. A blend of high-density polyethylene and polystyrene was used as a simulated mixed plastic. Stiffness was generally improved by the addition of fiber, as expected, but brittleness also increased. Pre-treatment of the wood filler with phenol-formaldehyde resins did...

ENZYMATIC POLYMERIZATION OF PHENOLS IN ROOM TEMPERATURE IONIC LIQUIDS

PubMed Central

Eker, Bilge; Zagorevski, Dmitri; Zhu, Guangyu; Linhardt, Robert J.; Dordick, Jonathan S.

2009-01-01

Soybean peroxidase (SBP) was used to catalyze the polymerization of phenols in room-temperature ionic liquids (RTILs). Phenolic polymers with number average molecular weights ranging from 1200 to 4100 D were obtained depending on the composition of the reaction medium and the nature of the phenol. Specifically, SBP was highly active in methylimidazolium-containing RTILs, including 1-butyl-3-methylimidazolium tetrafluoroborate (BMIM(BF4)), and 1-butyl-3-methylpyridinium tetrafluoroborate (BMPy(BF4)) with the ionic liquid content as high as 90% (v/v); the balance being aqueous buffer. Gel permeation chromatography and MALDI-TOF analysis indicated that higher molecular weight polymers can be synthesized in the presence of higher RTIL concentrations, with selective control over polymer size achieved by varying the RTIL concentration. The resulting polyphenols exhibited high thermostability and possessed thermosetting properties. PMID:20161409

Bioactive potential of Vitis labrusca L. grape juices from the Southern Region of Brazil: phenolic and elemental composition and effect on lipid peroxidation in healthy subjects.

PubMed

Toaldo, Isabela Maia; Cruz, Fernanda Alves; Alves, Tatiana de Lima; de Gois, Jefferson Santos; Borges, Daniel L G; Cunha, Heloisa Pamplona; da Silva, Edson Luiz; Bordignon-Luiz, Marilde T

2015-04-15

Grapes are rich in polyphenols with biologically active properties. Although the bioactive potential of grape constituents are frequently reported, the effects of Brazilian Vitis labrusca L. grape juices ingestion have not been demonstrated in humans. This study identified the phenolic and elemental composition of red and white grape juices and the effect of organic and conventional red grape juice consumption on lipid peroxidation in healthy individuals. Concentrations of anthocyanins, flavanols and phenolic acids and the in vitro antioxidant activity were significantly higher in the organic juice. The macro-elements K, Ca, Na and Mg were the most abundant minerals in all juices. The acute consumption of red grape juices promoted significant decrease of lipid peroxides in serum and TBARS levels in plasma. It is concluded that red V. labrusca L. grape juices produced in Southern Brazil showed lipid peroxidation inhibition abilities in healthy subjects, regardless of the cultivation system. Copyright © 2014 Elsevier Ltd. All rights reserved.

Influence of bottle storage time on colour, phenolic composition and sensory properties of sweet red wines.

PubMed

Marquez, Ana; Serratosa, Maria P; Merida, Julieta

2014-03-01

Changes in colour and phenolic composition in sweet red wines made from Merlot, Syrah and Tempranillo grapes were studied in order to assess the influence of bottle storage over a period of 12months. For this purpose, wine colour parameters, sensory analysis and concentrations of monomeric anthocyanins, pyranoanthocyanins, methylmethine-mediated condensation adducts, flavan3-ol derivatives and flavonols were measured. Hue increased and red colours decreased with the storage time, particularly over the first 3months. The concentrations of low molecular weight flavan-3-ol derivatives decreased with time due to the effect of their conversion into tannins of high molecular weight. In addition, the glycosylated flavonols decreased through hydrolysis to give the corresponding aglycones. Overall, the concentration of phenolic compounds decreased markedly with storage time, whereas the antioxidant activity in the wines remained constant throughout. A panel of expert tasters judged the colour, aroma and flavour of all initial and final wines to be acceptable. Copyright © 2013 Elsevier Ltd. All rights reserved.

Analytical optimization of a phenolic-rich herbal extract and supplementation in fermented milk containing sweet potato pulp.

PubMed

Ramos, Lorena Rodrigues; Santos, Jânio Sousa; Daguer, Heitor; Valese, Andressa Camargo; Cruz, Adriano Gomes; Granato, Daniel

2017-04-15

The aims of the present study were to optimize and characterize the phenolic composition of a herbal extract composed of green mate (Ilex paraguariensis), clove (Syzygium aromaticum), and lemongrass (Cymbopogon citratus) and to propose the addition of this polyphenol-rich extract to fermented milks (FM) with/without sweet potato pulp (Ipomoea batatas). Proximate composition, pH, acidity, instrumental texture profile, total phenolic content (TPC), antioxidant activity (AA) of all formulations were measured, and sensory attributes were also investigated. The addition of a lyophilized extract (1g 100g -1 ) containing 87.5% clove and 12.5% green mate increased the AA and TPC, while FM with added sweet potato pulp had the best sensory acceptance. The TPC and total reducing capacity had a slight change during 21days of storage. The data showed that herbal extracts and sweet potato pulp may be used to develop new dairy foods with potential functional properties. Copyright © 2016 Elsevier Ltd. All rights reserved.

Characterization of Flavonoid Glycosides from Fenugreek (Trigonella foenum-graecum) Crude Seeds by HPLC–DAD–ESI/MS Analysis

PubMed Central

Benayad, Zakia; Gómez-Cordovés, Carmen; Es-Safi, Nour Eddine

2014-01-01

Fenugreek (Trigonella foenum-graecum) is a medicinal plant which is widely used for its pharmacological properties. In this study the phenolic composition of fenugreek crude seeds originating from Morocco has been investigated. Extraction was performed from defatted seeds by a hydromethanolic solution using an Accelerated Solvent Extractor. HPLC technique coupled to negative ion electrospray ionization mass spectrometry and diode array detection was employed to identify the polyphenol in the obtained extract. The obtained results allowed the detection of 32 phenolic compounds among which various flavonoid glycosides and phenolic acids have been tentatively identified on the basis of their UV and MS spectra, and comparisons with standards when available, as well as with literature data. A systematic study of the obtained MS spectra and the observed fragmentation showed that most of the identified compounds were acylated and non-acylated flavonoids with apigenin, luteolin and kaempferol as aglycons. Hydroxycinnamic acids mostly dominated by caffeic acid derivatives were also detected. The quantitative analysis of the identified compounds showed that the phenolic composition of the studied crude fenugreek seeds was predominantly acylated and non-acylated flavone derivatives with apigenin as the main aglycon. PMID:25393509

Characterization of flavonoid glycosides from fenugreek (Trigonella foenum-graecum) crude seeds by HPLC-DAD-ESI/MS analysis.

PubMed

Benayad, Zakia; Gómez-Cordovés, Carmen; Es-Safi, Nour Eddine

2014-11-11

Fenugreek (Trigonella foenum-graecum) is a medicinal plant which is widely used for its pharmacological properties. In this study the phenolic composition of fenugreek crude seeds originating from Morocco has been investigated. Extraction was performed from defatted seeds by a hydromethanolic solution using an Accelerated Solvent Extractor. HPLC technique coupled to negative ion electrospray ionization mass spectrometry and diode array detection was employed to identify the polyphenol in the obtained extract. The obtained results allowed the detection of 32 phenolic compounds among which various flavonoid glycosides and phenolic acids have been tentatively identified on the basis of their UV and MS spectra, and comparisons with standards when available, as well as with literature data. A systematic study of the obtained MS spectra and the observed fragmentation showed that most of the identified compounds were acylated and non-acylated flavonoids with apigenin, luteolin and kaempferol as aglycons. Hydroxycinnamic acids mostly dominated by caffeic acid derivatives were also detected. The quantitative analysis of the identified compounds showed that the phenolic composition of the studied crude fenugreek seeds was predominantly acylated and non-acylated flavone derivatives with apigenin as the main aglycon.

Assessment of antioxidant activity of cane brown sugars by ABTS and DPPH radical scavenging assays: determination of their polyphenolic and volatile constituents.

PubMed

Payet, Bertrand; Shum Cheong Sing, Alain; Smadja, Jacqueline

2005-12-28

Seven cane brown sugars (four from La Réunion, two from Mauritius, and one from France) were investigated for their polyphenol content and volatile composition in relation to their free radical scavenging capacity determined by ABTS and DPPH assays. The thin layer coated on the sugar crystal was extracted by Soxhlet extractor with dichloromethane. The volatile compounds of brown sugars were studied by GC-MS, and 43 compounds were identified. The total phenolic content of brown sugars was determined according to the Folin-Ciocalteu method. Phenolic compounds were quantified in the brown sugar extracts by LC-UV-ESI-MS. Brown sugar aqueous solutions exhibited weak free radical scavenging activity in the DPPH assay and higher antioxidant activity in the ABTS assay at relatively high concentration. The brown sugar extracts showed interesting free radical scavenging properties despite the low concentration of phenolic and volatile compounds. Sugar is a common foodstuff traditionally used for its sweetening properties, which might be accompanied by antioxidant properties arising from molecules (polyphenols, Maillard products) other than sucrose of the cane brown sugars.

Effect of ultrafine grinding on physicochemical and antioxidant properties of dietary fiber from wine grape pomace.

PubMed

Zhu, Feng-Mei; Du, Bin; Li, Jun

2014-01-01

Wine grape pomace dietary fiber powders were prepared by superfine grinding, whose effects were investigated on the composition, functional and antioxidant properties of the wine grape pomace dietary fiber products. The results showed that superfine grinding could effectively pulverize the fiber particles to submicron scale. As particle size decrease, the functional properties (water-holding capacity, water-retention capacity, swelling capacity, oil-binding capacity, and nitrite ion absorption capacity) of wine grape pomace dietary fiber were significantly (p < 0.05) decreased and a redistribution of fiber components from insoluble to soluble fractions was observed. The antioxidant activities of wine grape pomace and dietary fiber before and after grinding were in terms of DPPH radical scavenging activity, ABTS diammonium salt radical scavenging activity, ferric reducing antioxidant power, and total phenolic content. Compared with dietary fiber before and after grinding, micronized insoluble dietary fiber showed increased ABTS radical scavenging activity, ferric reducing antioxidant power, and total phenolic content yet decreased DPPH radical scavenging activity. Positive correlations were detected between ABTS radical scavenging activity, ferric reducing antioxidant power, and total phenolic content.

An evaluation of the interfacial bond properties between carbon phenolic and glass phenolic composites

NASA Technical Reports Server (NTRS)

Jordan, Kelvin; Clinton, Raymond; Jeelani, Shaik

1989-01-01

The effects of moisture and surface finish on the mechanical and physical properties of the interfacial bond between the carbon/phenolic (C/P) and glass/phenolic (G/P) composite materials are presented. Four flat panel laminates were fabricated using the C/P and G/P materials. Of the four laminates, one panel was fabricated in which the C/P and G/P materials were cured simultaneously. It was identified as the cocure. The remaining laminates were processed with an initial simultaneous cure of the three C/P billets. Two surface finishes, one on each half, were applied to the top surface. Prior to the application and cure of the G/P material to the machined surface of the three C/P panels, each was subjected to the specific environmental conditioning. Types of conditioning included: (1) nominal fabrication environment, (2) a prescribed drying cycle, and (3) a total immersion in water at 160 F. Physical property tests were performed on specimens removed from the C/P materials of each laminate for determination of the specific gravity, residual volatiles and and resin content. Comparisons of results with shuttle solid rocket motor (SRM) nozzle material specifications verified that the materials used in fabricating the laminates met acceptance criteria and were representative of SRM nozzle materials. Mechanical property tests were performed at room temperature on specimens removed from the G/P, the C/P and the interface between the two materials for each laminate. The double-notched shear strength test was used to determine the ultimate interlaminar shear strength. Results indicate no appreciable difference in the C/P material of the four laminates with the exception of the cocure laminate, where 20 percent reduction in the strength was observed. The most significant effect and the ultimate strength was significantly reduced in the wet material. No appreciable variation was noted between the surface finishes in the wet laminate.

A Prediction of the Damping Properties of Hindered Phenol AO-60/polyacrylate Rubber (AO-60/ACM) Composites through Molecular Dynamics Simulation

NASA Astrophysics Data System (ADS)

Yang, Da-Wei; Zhao, Xiu-Ying; Zhang, Geng; Li, Qiang-Guo; Wu, Si-Zhu

2016-05-01

Molecule dynamics (MD) simulation, a molecular-level method, was applied to predict the damping properties of AO-60/polyacrylate rubber (AO-60/ACM) composites before experimental measures were performed. MD simulation results revealed that two types of hydrogen bond, namely, type A (AO-60) -OH•••O=C- (ACM), type B (AO-60) - OH•••O=C- (AO-60) were formed. Then, the AO-60/ACM composites were fabricated and tested to verify the accuracy of the MD simulation through dynamic mechanical thermal analysis (DMTA). DMTA results showed that the introduction of AO-60 could remarkably improve the damping properties of the composites, including the increase of glass transition temperature (Tg) alongside with the loss factor (tan δ), also indicating the AO-60/ACM(98/100) had the best damping performance amongst the composites which verified by the experimental.

Cobalt and sulfur co-doped nano-size TiO2 for photodegradation of various dyes and phenol.

PubMed

Siddiqa, Asima; Masih, Dilshad; Anjum, Dalaver; Siddiq, Muhammad

2015-11-01

Various compositions of cobalt and sulfur co-doped titania nano-photocatalyst are synthesized via sol-gel method. A number of techniques including X-ray diffraction (XRD), ultraviolet-visible (UV-Vis), Rutherford backscattering spectrometry (RBS), thermal gravimetric analysis (TGA), Raman, N2 sorption, electron microscopy are used to examine composition, crystalline phase, morphology, distribution of dopants, surface area and optical properties of synthesized materials. The synthesized materials consisted of quasispherical nanoparticles of anatase phase exhibiting a high surface area and homogeneous distribution of dopants. Cobalt and sulfur co-doped titania demonstrated remarkable structural and optical properties leading to an efficient photocatalytic activity for degradation of dyes and phenol under visible light irradiations. Moreover, the effect of dye concentration, catalyst dose and pH on photodegradation behavior of environmental pollutants and recyclability of the catalyst is also examined to optimize the activity of nano-photocatalyst and gain a better understanding of the process. Copyright © 2015. Published by Elsevier B.V.

Strawberries from integrated pest management and organic farming: phenolic composition and antioxidant properties.

PubMed

Fernandes, Virgínia C; Domingues, Valentina F; de Freitas, Victor; Delerue-Matos, Cristina; Mateus, Nuno

2012-10-15

Consumer awareness, pesticide and fertilizer contaminations and environmental concerns have resulted in significant demand for organically grown farm produce. Consumption of berries has become popular among health-conscious consumers due to the high levels of valuable antioxidants, such as anthocyanins and other phenolic compounds. The present study evaluated the influence that organic farming (OF) and integrated pest management (IPM) practise exert on the total phenolic content in 22 strawberry samples from four varieties. Postharvest performance of OF and IPM strawberries grown in the same area in the centre of Portugal and harvested at the same maturity stage were compared. Chemical profiles (phenolic compounds) were determined with the aid of HPLC-DAD/MS. Total phenolic content was higher for OF strawberry extracts. This study showed that the main differences in bioactive phytochemicals between organically and IPM grown strawberries concerned their anthocyanin levels. Organically grown strawberries were significantly higher in antioxidant activity than were the IPM strawberries, as measured by DPPH and FRAP assays. Copyright © 2012 Elsevier Ltd. All rights reserved.

Characterization and quantitation of anthocyanins and other phenolics in native Andean potatoes.

PubMed

Giusti, M Monica; Polit, Maria Fernanda; Ayvaz, Huseyin; Tay, David; Manrique, Ivan

2014-05-14

Andean potatoes are gaining popularity not only for their appealing colors and culinary uses but also for their potential higher content of polyphenolic compounds. The objective of this study was to identify potato varieties with increased phenolic content. This was achieved through characterization and quantitation of the phenolic composition in 20 varieties of native Andean potatoes from 4 different Solanum species with different colors. Major quantitative and qualitative differences among evaluated samples were more dependent on the coloration of the extracted sample rather than on the species. The most predominant anthocyanidins were petunidin-3-coumaroylrutinoside-5-glucoside and pelargonidin-3-coumaroylrutinoside-5-glucoside in purple and red potato extracts, respectively, while chlorogenic acid and its isomers were the main phenolic compund (43% of the total phenolic content). Our study suggested that the appropriate selection of native potatoes could provide new sources of polyphenolics with health promoting properties and natural pigments with increased stability for food applications.

Extraction and HPLC analysis of phenolic compounds in leaves, stalks, and textile fibers of Urtica dioica L.

PubMed

Pinelli, Patrizia; Ieri, Francesca; Vignolini, Pamela; Bacci, Laura; Baronti, Silvia; Romani, Annalisa

2008-10-08

In the present study the phenolic composition of leaves, stalks, and textile fiber extracts from Urtica dioica L. is described. Taking into account the increasing demand for textile products made from natural fibers and the necessity to create sustainable "local" processing chains, an Italian project was funded to evaluate the cultivation of nettle fibers in the region of Tuscany. The leaves of two nettle samples, cultivated and wild (C and W), contain large amounts of chlorogenic and 2- O-caffeoylmalic acid, which represent 71.5 and 76.5% of total phenolics, respectively. Flavonoids are the main class in the stalks: 54.4% of total phenolics in C and 31.2% in W samples. Anthocyanins are second in quantitative importance and are present only in nettle stalks: 28.6% of total phenolics in C and 24.4% in W extracts. Characterization of phenolic compounds in nettle extracts is an important result with regard to the biological properties (antioxidant and antiradical) of these metabolites for their possible applications in various industrial activities, such as food/feed, cosmetics, phytomedicine, and textiles.

Deconvoluting effects of vine and soil properties on grape berry composition.

PubMed

Zerihun, Ayalsew; McClymont, Lexie; Lanyon, Dean; Goodwin, Ian; Gibberd, Mark

2015-01-01

Grape berry composition is influenced by several factors including grapevine and soil properties and their interactions. Understanding how these factors interact to determine berry composition is integral to producing berries with desired composition. Here we used extensive spatio-temporal data to identify significant vine and soil features that influence Shiraz berry composition. The concentrations of berry flavonoids (anthocyanins, tannin and total phenolics), total soluble solids and pH were typically negatively associated with canopy, crop and berry size factors whereas titratable acidity was positively associated. The strengths of the associations, however, were generally greater with the crop and berry size factors than with the canopy size factor. The analyses also resolved separate influences of berry and crop size on berry composition. Soil properties had significant influences on berry composition; however, when influences of soil factors on vine-attributes were accounted for, the apparent effects of soil factors on berry composition were largely non-existent. At each site, variations in berry composition were more strongly associated with crop and berry size than with canopy size factors. Apparent influences of soil properties on berry composition are indirect, being mediated via their effects on vine attributes (canopy, crop and berry sizes). © 2014 Society of Chemical Industry.

Variability of Virgin Olive Oil Phenolic Compounds in a Segregating Progeny from a Single Cross in Olea europaea L. and Sensory and Nutritional Quality Implications

PubMed Central

Pérez, Ana G.; León, Lorenzo; Pascual, Mar; Romero-Segura, Carmen; Sánchez-Ortiz, Araceli; de la Rosa, Raúl; Sanz, Carlos

2014-01-01

Virgin olive oil phenolic compounds are responsible for its nutritional and sensory quality. The synthesis of phenolic compounds occurs when enzymes and substrates meet as olive fruit is crushed during the industrial process to obtain the oil. The genetic variability of the major phenolic compounds of virgin olive oil was studied in a progeny of the cross of Picual x Arbequina olive cultivars (Olea europaea L.). They belong to four different groups: compounds that included tyrosol or hydroxytyrosol in their molecules, lignans, flavonoids, and phenolic acids. Data of phenolics in the oils showed that the progeny displayed a large degree of variability, widely transgressing the genitor levels. This high variability can be of interest on breeding programs. Thus, multivariate analysis allowed to identify genotypes within the progeny particularly interesting in terms of phenolic composition and deduced organoleptic and nutritional quality. The present study has demonstrated that it is possible to obtain enough degree of variability with a single cross of olive cultivars for compounds related to the nutritional and organoleptic properties of virgin olive oil. PMID:24651694

Berry Phenolics of Grapevine under Challenging Environments

PubMed Central

Teixeira, António; Eiras-Dias, José; Castellarin, Simone D.; Gerós, Hernâni

2013-01-01

Plant phenolics have been for many years a theme of major scientific and applied interest. Grape berry phenolics contribute to organoleptic properties, color and protection against environmental challenges. Climate change has already caused significant warming in most grape-growing areas of the world, and the climatic conditions determine, to a large degree, the grape varieties that can be cultivated as well as wine quality. In particular, heat, drought and light/UV intensity severely affect phenolic metabolism and, thus, grape composition and development. In the variety Chardonnay, water stress increases the content of flavonols and decreases the expression of genes involved in biosynthesis of stilbene precursors. Also, polyphenolic profile is greatly dependent on genotype and environmental interactions. This review deals with the diversity and biosynthesis of phenolic compounds in the grape berry, from a general overview to a more detailed level, where the influence of environmental challenges on key phenolic metabolism pathways is approached. The full understanding of how and when specific phenolic compounds accumulate in the berry, and how the varietal grape berry metabolism responds to the environment is of utmost importance to adjust agricultural practices and thus, modify wine profile. PMID:24030720

Variability of virgin olive oil phenolic compounds in a segregating progeny from a single cross in Olea europaea L. and sensory and nutritional quality implications.

PubMed

Pérez, Ana G; León, Lorenzo; Pascual, Mar; Romero-Segura, Carmen; Sánchez-Ortiz, Araceli; de la Rosa, Raúl; Sanz, Carlos

2014-01-01

Virgin olive oil phenolic compounds are responsible for its nutritional and sensory quality. The synthesis of phenolic compounds occurs when enzymes and substrates meet as olive fruit is crushed during the industrial process to obtain the oil. The genetic variability of the major phenolic compounds of virgin olive oil was studied in a progeny of the cross of Picual x Arbequina olive cultivars (Olea europaea L.). They belong to four different groups: compounds that included tyrosol or hydroxytyrosol in their molecules, lignans, flavonoids, and phenolic acids. Data of phenolics in the oils showed that the progeny displayed a large degree of variability, widely transgressing the genitor levels. This high variability can be of interest on breeding programs. Thus, multivariate analysis allowed to identify genotypes within the progeny particularly interesting in terms of phenolic composition and deduced organoleptic and nutritional quality. The present study has demonstrated that it is possible to obtain enough degree of variability with a single cross of olive cultivars for compounds related to the nutritional and organoleptic properties of virgin olive oil.

The position of prenylation of isoflavonoids and stilbenoids from legumes (Fabaceae) modulates the antimicrobial activity against Gram positive pathogens.

PubMed

Araya-Cloutier, Carla; den Besten, Heidy M W; Aisyah, Siti; Gruppen, Harry; Vincken, Jean-Paul

2017-07-01

The legume plant family (Fabaceae) is a potential source of antimicrobial phytochemicals. Molecular diversity in phytochemicals of legume extracts was enhanced by germination and fungal elicitation of seven legume species, as established by RP-UHPLC-UV-MS. The relationship between phytochemical composition, including different types of skeletons and substitutions, and antibacterial properties of extracts was investigated. Extracts rich in prenylated isoflavonoids and stilbenoids showed potent antibacterial activity against Listeria monocytogenes and methicillin-resistant Staphylococcus aureus at concentrations between 0.05 and 0.1% (w/v). Prenylated phenolic compounds were significantly (p<0.01) correlated with the antibacterial properties of the extracts. Furthermore, the position of the prenyl group within the phenolic skeleton also influenced the antibacterial activity. Overall, prenylated phenolics from legume seedlings can serve multiple purposes, e.g. as phytoestrogens they can provide health benefits and as natural antimicrobials they offer preservation of foods. Copyright © 2017 Elsevier Ltd. All rights reserved.

Tunable mesoporous bilayer photonic resins with chiral nematic structures and actuator properties.

PubMed

Khan, Mostofa K; Hamad, Wadood Y; Maclachlan, Mark J

2014-04-16

Chiral nematic structures with different helical pitch from layer to layer are embedded into phenol-formaldehyde bilayer resin composite films using cellulose nanocrystals (CNCs) as templates. Selective removal of CNCs results in mesoporous resins with different pore size and helical pitch between the layers. Consequently, these materials exhibit photonic properties by selectively reflecting lights of two different wavelengths and concomitant actuation properties. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Nanographene reinforced carbon/carbon composites

NASA Astrophysics Data System (ADS)

Bansal, Dhruv

Carbon/Carbon Composites (CCC) are made of carbon reinforcement in carbon matrix and have high thermal stability and fatigue resistance. CCC are used in nose cones, heat shields and disc brakes of aircrafts due to their exceptional mechanical properties at high temperature. The manufacturing process of CCC involves a carbonization stage in which unwanted elements, except carbon, are eliminated from the polymer precursor. Carbonization results in the formation of voids and cracks due to the thermal mismatch between the reinforcement and the matrix and expulsion of volatiles from the polymer matrix. Thermal cracks and voids decrease the density and mechanical properties of the manufactured CCC. In this work, Nanographene Platelets (NGP) were explored as nanofillers to fill the voids/cracks and reduce thermal shrinkage in CCC. They were first compared with Vapor Grown Carbon Nanofibers (VGCNF) by dispersion of different concentrations (0.5wt%, 1.5wt%, 3wt%) in resole-type phenolic resin and were characterized to explore their effect on rheology, heat of reaction and wetting behavior. The dispersions were then cured to form nanocomposites and were characterized for morphology, flexure and thermal properties. Finally, NGP were introduced into the carbon/carboncomposites in two stages, first by spraying in different concentrations (0.5wt%, 1.5wt%, 3wt%, 5wt %) during the prepreg formation and later during densification by directly mixing in the corresponding densification mix. The manufactured NGP reinforced CCC were characterized for microstructure, porosity, bulk density and mechanical properties (Flexure and ILSS) which were further cross-checked by non-destructive techniques (vibration and ultrasonic). In this study, it was further found that at low concentration (≤ 1.5 wt%) NGP were more effective in increasing the heat of reaction and in decreasing the viscosity of the phenolic resin. The decrease in viscosity led to better wetting properties of NGP / phenolic dispersions compared to VGCNF/phenolic dispersions. In nanocomposites, at low concentration (≤ 1.5 wt%), NGP were effective in increasing the flexure strength, char content and lowering the porosity and coefficient of thermal expansion of neat phenolic resin. At higher concentration (>1.5wt%), NGP had a tendency to agglomerate and lost their effectiveness. The behavior observed in nanocomposites continued in manufactured CCC. The highest Inter Laminar Shear Strength (ILSS), flexure strength/modulus, stiffness and density was observed at 1.5 wt% NGP. In CCC at concentrations > 1.5 wt%, the properties (ILSS, flexure, stiffness, density) decreased due to agglomeration but they were still higher compared to that of neat CCC (without NGP).

Physicochemical and nutritional properties of pigmented rice subjected to different degrees of milling

USDA-ARS?s Scientific Manuscript database

Recent studies have reported the health benefits of pigmented rice cultivars due to the presence of bioactive compounds in its bran layer of caryopsis. This study evaluated the proximate composition, colour, total flavonoids, anthocyanins and proanthocyanidins contents, as well as the total phenolic...

Polishing and parboiling effect on the nutritional and technological properties of pigmented rice

USDA-ARS?s Scientific Manuscript database

This study aims to evaluate the effects of polishing and parboiling on proximate composition, structure, phenolic compounds, antioxidant activity, cooking time and hardness of IAC-600 black rice cultivar and MPB-10 red rice lineage. Proximate analysis and light micrographs revealed higher migration ...

Porous Media and Mixture Models for Hygrothermal Behavior of Phenolic Composites

NASA Technical Reports Server (NTRS)

Sullivan, Roy M.; Stokes, Eric H.

1999-01-01

Theoretical models are proposed to describe the interaction of water with phenolic polymer. The theoretical models involve the study of the flow of a viscous fluid through a porous media and the thermodynamic theory of mixtures. From the theory, a set of mathematical relations are developed to simulate the effect of water on the thermostructural response of phenolic composites. The expressions are applied to simulate the measured effect of water in a series of experiments conducted on carbon phenolic composites.

Wheat-water chestnut flour blends: effect of baking on antioxidant properties of cookies.

PubMed

Shafi, Musarat; Baba, Waqas N; Masoodi, Farooq Ahmad; Bazaz, Rafiya

2016-12-01

Proximate composition, mineral content, functional, pasting and antioxidant properties of water chestnut flour (WCF) were compared with refined wheat flour. WCF showed higher phenolic (4.25 gGAE/1000 g), flavonoid (1.92 g QE/1000 g) and mineral content (K, Mg, Zn, Cu) than wheat flour. WCF showed greater retrogradation tendency but lower peak viscosity than wheat flour. Wheat flour - WCF blends and cookies were evaluated for water activity, physical & textural properties. Water activity of cookies decreased significantly (0.415-0.311) with increase in level of WCF in wheat flour. Total phenolic content, flavonoid content and antioxidant activity (DPPH• scavenging capacity, FRAP) of WCF - wheat flour blends as well as their cookies was also determined. Baking led to a greater increase in DPPH• scavenging capacity of WCF cookies (33.8%) than WF cookies (25%). Baking had a similar effect on FRAP value. Wheat flour cookies showed a decrease of 51%, and 62% while WCF cookies showed a decrease of 36%, and 34% in TPC and TFC values respectively. WCF cookies thus showed better retention of antioxidant activities suggesting greater stability of WC phenolics than wheat phenolics. Sensory analysis showed cookies made from water chestnut (100%) had fair acceptability due to their characteristic flavor. Thus, water chestnut flour serves both as a gluten free as well as antioxidant rich flour for production of cookies.

Volatile composition and sensory properties of Vanilla × tahitensis bring new insights for vanilla quality control.

PubMed

Brunschwig, Christel; Rochard, Sophie; Pierrat, Alexandre; Rouger, Anne; Senger-Emonnot, Perrine; George, Gérard; Raharivelomanana, Phila

2016-02-01

Vanilla × tahitensis produced in French Polynesia has a unique flavour among vanilla species. However, data on volatiles and sensory properties remain limited. In this study, the volatile composition and sensory properties of V. × tahitensis from three Polynesian cultivars and two origins (French Polynesia/Papua New Guinea) were determined by gas chromatography-mass spectrometry and quantitative descriptive analysis, respectively, and compared to Vanilla planifolia. Vanilla species, origins and cultivars were differentiated by their volatile and sensory profiles using principal component analysis. The V. × tahitensis flavour from French Polynesia was characterized by a well-balanced sensory profile, having strong anise and caramel notes due to high levels of anisyl compounds. V. × tahitensis from Papua New Guinea was distinct from that of French Polynesia, having strong spicy, fruity, brown rum notes due to p-vinylguaiacol, p-cresol and esters. Vanilla planifolia showed stronger phenolic, woody, smoky notes due to guaiacol, creosol and phenol, which were found to be biomarkers of the species. Vanilla sensory properties were linked by partial least squares regression to key volatile compounds like guaiacol or creosol, which are indicators of lower quality. This study brings new insights to vanilla quality control, with a focus on key volatile compounds, irrespective of origin. © 2015 Society of Chemical Industry.

Fennel (Foeniculum vulgare Mill. subsp. piperitum) florets, a traditional culinary spice in Italy: evaluation of phenolics and volatiles in local populations, and comparison with the composition of other plant parts.

PubMed

Ferioli, Federico; Giambanelli, Elisa; D'Antuono, L Filippo

2017-12-01

Wild fennel (Foeniculum vulgare Mill. subsp. piperitum) florets are used as a typical spice in central and southern Italy. Although fennel (Foeniculum vulgare Mill.), belonging to the Apiaceae (syn. Umbelliferae) family, is a well-known vegetable and aromatic plant, whose main phytochemical compounds have been extensively analysed and investigated as flavouring agents and for their putative health promoting functions, its florets have not been specifically considered up to now. Therefore, the volatile and phenolic composition of florets from an Italian wild fennel crop was determined at different developmental stages, and compared to that of leaves and fruits. Moreover, florets of nine Italian wild fennel populations of different geographical origin from northern-central Italy were also analysed. The total phenolic amount increased from leaves to florets, reaching its highest value in early florets, at 58 012 mg kg -1 of dry matter (DM), then constantly decreased in fruits. In florets of wild populations, phenolics ranged from 6666 to 43 368 mg kg -1 DM. The total amount of volatile compounds was more than twice higher in florets (21 449 mg kg -1 DM) than in leaves (10 470 mg kg -1 DM), reaching its highest value in fruits (50 533 mg kg -1 DM). Estragole and trans-anethole were the main compounds of the volatile fraction. Total volatiles ranged from 24 367 to 60 468 mg kg -1 DM in florets of local populations. Significant changes in the total amount and profile of both phenolic and volatile compounds occurred during plant development. The consistent increase of estragole at later developmental stages supported the claim of different sensory properties of florets and fruits. Geographical origin significantly affected phenolic and volatile composition of wild fennel florets. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Characterization of phenolic compounds in flowers of wild medicinal plants from Northeastern Portugal.

PubMed

Barros, Lillian; Dueñas, Montserrat; Carvalho, Ana Maria; Ferreira, Isabel C F R; Santos-Buelga, Celestino

2012-05-01

Crataegus monogyna, Cytisus multiflorus, Malva sylvestris and Sambucus nigra have been used as important medicinal plants in the Iberian Peninsula since a long time ago, and are claimed to have various health benefits. This study aimed to determine the phenolic profile and composition of wild medicinal flowers of those species. The analysis was performed by HPLC-DAD-ESI/MS. Flavonoids, and particularly flavonols and flavones, were the main groups in almost all the studied samples. C. multiflorus sample gave the highest levels of total flavonoids (54.5 mg/gdw), being a chrysin derivative the most abundant flavone found (22.3 mg/gdw). C. monogyna revealed the highest concentration in phenolic acids (5.5 mg/gdw) that were not found in C. multiflorus sample; 5-O-caffeoylquinic acid was the most abundant phenolic acid found in the first species, being a procyanidin trimer also found (1.4 mg/gdw). Kaempferol-3-O-rutinoside (0.84 mg/gdw) and quercetin-3-O-rutinoside (14.9 mg/gdw) were the main flavonols present in M. sylvestris and S. nigra, respectively. Due to the well established antioxidant activity of phenolic compounds, the studied wild medicinal flowers could be selected for processing extracts with health-promoting properties or to be incorporate into functional beverages or products with bioactive properties related to oxidative stress. Copyright © 2012 Elsevier Ltd. All rights reserved.

Spectroscopy analysis of phenolic and sugar patterns in a food grade chestnut tannin.

PubMed

Ricci, A; Lagel, M-C; Parpinello, G P; Pizzi, A; Kilmartin, P A; Versari, A

2016-07-15

Tannin of chestnut (Castanea sativa Mill.) wood, commonly used in winemaking was characterised with a spectroscopy qualitative approach that revealed its phenolic composition: several vibrational diagnostic bands assigned using the Attenuated Total Reflectance-Infrared Spectroscopy, and fragmentation patterns obtained using the Laser-Desorption-Ionization Time-of-Flight technique evidenced polygalloylglucose, e.g. castalagin/vescalagin-like structures as the most representative molecules, together with sugar moieties. The implication of these findings on winemaking application and the potential influence of the chemical structure on the sensory properties of wine are discussed. Copyright © 2016 Elsevier Ltd. All rights reserved.

Antioxidant and antimicrobial phenolic compounds from extracts of cultivated and wild-grown Tunisian Ruta chalepensis.

PubMed

Ouerghemmi, Ines; Bettaieb Rebey, Iness; Rahali, Fatma Zohra; Bourgou, Soumaya; Pistelli, Luisa; Ksouri, Riadh; Marzouk, Brahim; Saidani Tounsi, Moufida

2017-04-01

The antioxidant and antibacterial activities of phenolic compounds from cultivated and wild Tunisian Ruta chalepensis L. leaves, stems, and flowers were assessed. The leaves and the flowers exhibited high but similar total polyphenol, flavonoid, and tannin content. Moreover, two organs showed strong, although not significantly different, total antioxidant activity, 2,2-diphenyl-1-picrylhydrazyl scavenging ability, and reducing power. Investigation of the phenolic composition showed that vanillic acid and coumarin were the major compounds in the two organs, with higher percentages in the cultivated organs than in the spontaneous organs. Furthermore, R. chalepensis extracts showed marked antibacterial properties against human pathogen strains, and the activity was organ- and origin-dependent. Spontaneous stems had the strongest activity against Pseudomonas aeruginosa. From these results, it was concluded that domestication of Ruta did not significantly affect its chemical composition and consequently the possibility of using R. chalpensis organs as a potential source of natural antioxidants and as an antimicrobial agent in the food industry. Copyright © 2016. Published by Elsevier B.V.

Phenolic acid composition and antioxidant properties of Malaysian honeys.

PubMed

Khalil, M I; Alam, N; Moniruzzaman, M; Sulaiman, S A; Gan, S H

2011-08-01

The phenolic acid and flavonoid contents of Malaysian Tualang, Gelam, and Borneo tropical honeys were compared to those of Manuka honey. Ferric reducing/antioxidant power assay (FRAP) and the 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical-scavenging activities were also quantified. All honey extracts exhibited high phenolic contents (15.21 ± 0.51- 42.23 ± 0.64 mg/kg), flavonoid contents (11.52 ± 0.27- 25.31 ± 0.37 mg/kg), FRAP values (892.15 ± 4.97- 363.38 ± 10.57 μM Fe[II]/kg), and high IC₅₀ of DPPH radical-scavenging activities (5.24 ± 0.40- 17.51 ± 0.51 mg/mL). Total of 6 phenolic acids (gallic, syringic, benzoic, trans-cinnamic, p-coumaric, and caffeic acids) and 5 flavonoids (catechin, kaempferol, naringenin, luteolin, and apigenin) were identified. Among the Malaysian honey samples, Tualang honey had the highest contents of phenolics, and flavonoids, and DPPH radical-scavenging activities. We conclude that among Malaysian honey samples, Tualang honey is the richest in phenolic acids, and flavonoid compounds, which have strong free radical-scavenging activities. © 2011 Institute of Food Technologists®

Phenolic composition, antioxidant capacity of Salvia verticcilata and effect on multidrug resistant bacteria by flow-cytometry.

PubMed

Tekeli, Yener; Karpuz, Esra; Danahaliloglu, Hatice; Bucak, Serbay; Guzel, Yelda; Erdmann, Helmuth

2014-01-01

Antioxidants are of great importance for preventing oxidative stress that may cause several degenerative diseases. Studies have indicated phytochemicals have high free-radical scavenging activity, which helps to reduce the risk of chronic diseases. The aim of the present study is the determination of antioxidant properties, polyphenolic content and multidrug resistant bacteria of Salvia verticcilata L. Methanol was used as the extraction solvent. The total phenolic content was calculated using Folin-Ciocalteau method and phenolic composition was determined by HPLC. The radical scavenging activity of plant was evaluated in vitro based on the reduction of the stable DPPH free radical. The reducing capacity was identified by using the FRAP method. The ability of Salvia verticcilata L. to increase the permeability of multidrug resistant bacterial cells was conducted by flow cytometric assay on Listeria innocua and E-coli. The amount of total phenolics was found to be 347.5 mg GA/g extract. The IC50 value and FRAP assay are 0.61, and 0.944 respectively, Free radical scavenging effect and FRAP values are less than synthetic antioxidant compounds (BHA and BHT). Eight phenolic compounds were found in Salvia verticcilata L. Intense concentration of S. verticcilata L. has destroyed 97 % of living cells for Listeria innocua and 94.86% for E-coli. This study shows that methanolic extracts of Salvia verticcilata L. is a potential source of natural antioxidants and antimicrobial agent and can form the basis for pharmacological studies.

Piper betle leaves: profiling phenolic compounds by HPLC/DAD-ESI/MS(n) and anti-cholinesterase activity.

PubMed

Ferreres, Federico; Oliveira, Andreia P; Gil-Izquierdo, Angel; Valentão, Patrícia; Andrade, Paula B

2014-01-01

Piper betle L. is a widely distributed plant in the tropical and subtropical regions, its leaves being largely consumed as a masticator and mouth freshener. The purposes of this work were to characterise the phenolic profile of this species and to improve knowledge of its anti-cholinesterase properties. The phenolic composition of P. betle leaf aqueous and ethanol extracts was characterised by HPLC coupled with a diode-array detector and combined with electrospray ionisation tandem MS, and in vitro cholinesterase inhibitory capacity of both extracts was assessed by spectrophotometric microassays. The effect on neuronal cells (SH-SY5Y) viability was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide reduction and lactate dehydrogenase leakage. Twelve phenolic compounds, comprising a phenylpropanoid, five cinnamoyl and six flavonoids derivatives were identified in P. betle leaves. Hydroxychavicol was the major compound in both extracts; however, the aqueous extract presented a greater diversity of compounds. Both extracts showed strong activity against both acetyl- and butyrylcholinesterase, which can be due, at least partially, to the phenolic composition. Furthermore, the aqueous extract proved to be cytotoxic to human neuroblastoma cells at concentrations higher than 500 µg/mL. The results suggest that the consumption of P. betle leaves as an infusion can have a positive impact in the prevention and treatment of neurodegenerative diseases. Apigenin and luteolin derivatives are reported for the first time in this species. Copyright © 2014 John Wiley & Sons, Ltd.

Humic acids: Structural properties and multiple functionalities for novel technological developments.

PubMed

de Melo, Bruna Alice Gomes; Motta, Fernanda Lopes; Santana, Maria Helena Andrade

2016-05-01

Humic acids (HAs) are macromolecules that comprise humic substances (HS), which are organic matter distributed in terrestrial soil, natural water, and sediment. HAs differ from the other HS fractions (fulvic acid and humins) in that they are soluble in alkaline media, partially soluble in water, and insoluble in acidic media. Due to their amphiphilic character, HAs form micelle-like structures in neutral to acidic conditions, which are useful in agriculture, pollution remediation, medicine and pharmaceuticals. HAs have undefined compositions that vary according to the origin, process of obtainment, and functional groups present in their structures, such as quinones, phenols, and carboxylic acids. Quinones are responsible for the formation of reactive oxygen species (ROS) in HAs, which are useful for wound healing and have fungicidal/bactericidal properties. Phenols and carboxylic acids deprotonate in neutral and alkaline media and are responsible for various other functions, such as the antioxidant and anti-inflammatory properties of HAs. In particular, the presence of phenolic groups in HAs provides antioxidant properties due to their free radical scavenging capacity. This paper describes the main multifunctionalities of HAs associated with their structures and properties, focusing on human health applications, and we note perspectives that may lead to novel technological developments. To the best of our knowledge, this is the first review to address this topic from this approach. Copyright © 2015 Elsevier B.V. All rights reserved.

Foam mat drying of Tommy Atkins mango: Effects of air temperature and concentrations of soy lecithin and carboxymethylcellulose on phenolic composition, mangiferin, and antioxidant capacity.

PubMed

Lobo, Francine Albernaz; Nascimento, Manuela Abreu; Domingues, Josiane Roberto; Falcão, Deborah Quintanilha; Hernanz, Dolores; Heredia, Francisco J; de Lima Araujo, Kátia Gomes

2017-04-15

In this study, foam mat drying was applied to Tommy Atkins mango. Using a multifactorial design, the effect of soy lecithin (L) and carboxymethylcellulose (CMC) used as foam stabilizers (0-1.50g/100g), as well as temperature (T) (53-87°C), on phenolic content and antioxidant capacity of mango were evaluated. Mango pulp contains antioxidant, such as mangiferin, that can be utilized in foods to enhance their functional properties. Our results indicated that L and T had negative effects (p<0.05) on the phenolic content and antioxidant capacity, whereas CMC had a positive effect (p<0.05). Increasing the total amount of phenolic compounds present in dried mango contributed to the higher antioxidant capacity after the drying process. This study concluded that a drying T of 80°C, and a concentration of 0.30g/100g of CMC and L are optimal for increased retention of phenolic compounds and antioxidant capacity. Copyright © 2016 Elsevier Ltd. All rights reserved.

Development and optimisation of an HPLC-DAD-ESI-Q-ToF method for the determination of phenolic acids and derivatives.

PubMed

Restivo, Annalaura; Degano, Ilaria; Ribechini, Erika; Colombini, Maria Perla

2014-01-01

A method for the HPLC-MS/MS analysis of phenols, including phenolic acids and naphtoquinones, using an amide-embedded phase column was developed and compared to the literature methods based on classical C18 stationary phase columns. RP-Amide is a recently developed polar embedded stationary phase, whose wetting properties mean that up to 100% water can be used as an eluent. The increased retention and selectivity for polar compounds and the possibility of working in 100% water conditions make this column particularly interesting for the HPLC analysis of phenolic acids and derivatives. In this study, the chromatographic separation was optimised on an HPLC-DAD, and was used to separate 13 standard phenolic acids and derivatives. The method was validated on an HPLC-ESI-Q-ToF. The acquisition was performed in negative polarity and MS/MS target mode. Ionisation conditions and acquisition parameters for the Q-ToF detector were investigated by working on collision energies and fragmentor potentials. The performance of the method was fully evaluated on standards. Moreover, several raw materials containing phenols were analysed: walnut, gall, wine, malbec grape, French oak, red henna and propolis. Our method allowed us to characterize the phenolic composition in a wide range of matrices and to highlight possible matrix effects.

Phenolic composition and antioxidant capacity of Ugni molinae Turcz. leaves of different genotypes.

PubMed

Peña-Cerda, Marcelo; Arancibia-Radich, Jorge; Valenzuela-Bustamante, Paula; Pérez-Arancibia, Rodrigo; Barriga, Andrés; Seguel, Ivette; García, Lorena; Delporte, Carla

2017-01-15

Ugni molinae Turcz. is a native shrub of Chile, known for its edible berries and its leaves, which have been the focus of recent attention, as a good source of phenolic compounds to be used in cosmetics and food products. The aim of this study was to assess the differences in the phenolic composition and antioxidant capacity of the ethanolic extracts from the leaves of 10 genotypes of U. molinae, that were cultivated under the same soil, climate and agronomical management. Antioxidant activity was assessed by complementary methods (ORAC-Fl, FRAP and DPPH assay), phenolic composition of each extract was analyzed by LC-MS. Phenolic and flavonoid total contents were determined by Folin-Ciocalteu and AlCl3 methods. Significative differences were found by these methods, and ellagitannins, gallic acid derivatives and flavonols were identified as responsible for these differences, showing the influence of the genotype on the phenolic composition of U. molinae leaves. Copyright © 2016 Elsevier Ltd. All rights reserved.

Evaluation of Radical Scavenging Activity of Sempervivum tectorum and Corylus avellana Extracts with Different Phenolic Composition.

PubMed

Alberti, Ágnes; Riethmüller, Eszter; Béni, Szabolcs; Kéry, Ágnes

2016-04-01

Semnpervivum tectorum L. and Corylus avellana L. are traditional herbal remedies exhibiting antioxidant activity and representing diverse phenolic composition. The aim of this study was to reveal the contribution of certain compounds to total radical scavenging activity by studying S. tectorum and C. avellana extracts prepared with solvents of different selectivity for diverse classes of phenolics. Antioxidant activity of S. tectorum and C. avellana samples was determined in the ABTS and DPPH radical scavenging assays, and phenolic composition was evaluated by high-performance liquid chromatography/electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS). Correlations between antioxidant activity and phenolic content of houseleek extracts have been revealed. Significant differences regarding antioxidant activity have been shown between S. tectorum 80% (v/v) methanol extract and its fractions. Additionally, synergism among the constituents present together in the whole extract was assumed. Significantly higher radical scavenging activity of hazel extracts has been attributed to the differences in phenolic composition compared with houseleek extracts.

Variation in cell wall composition among forage maize (Zea mays L.) inbred lines and its impact on digestibility: analysis of neutral detergent fiber composition by pyrolysis-gas chromatography-mass spectrometry.

PubMed

Fontaine, Anne-Sophie; Bout, Siobhán; Barrière, Yves; Vermerris, Wilfred

2003-12-31

Cell wall digestibility is an important determinant of forage quality, but the relationship between cell wall composition and digestibility is poorly understood. We analyzed the neutral detergent fiber (NDF) fraction of nine maize inbred lines and one brown midrib3 mutant with pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS). Among 29 pyrolysis fragments that were quantified, two carbohydrate-derived and six lignin-derived fragments showed statistically significant genetic variation. The pyrolysis products 4-vinyl phenol and 2,6-dimethoxy-4-vinyl phenol were negatively correlated with digestibility, whereas furfural and 3-(4-hydroxyphenyl)-3-oxopropanal showed a positive correlation with digestibility. Linear discriminant analysis of the pyrolysis data resulted in the resolution of groups of inbred lines with different digestibility properties based on their chemical composition. These analyses reveal that digestibility is governed by complex interactions between different cell wall compounds, but that several pyrolysis fragments can be used as markers to distinguish between maize lines with different digestibility.

Antioxidant activity of insect gall extracts of Pistacia integerrima.

PubMed

Eshwarappa, Ravi Shankara Birur; Lakshmikantha, Ramachandra Yarappa; Subaramaihha, Sundara Rajan; Subbaiah, Sujan Ganapathy Pasura; Surendranath, Austin Richard; Dhananjaya, Bhadrapura Lakkappa

2015-01-01

Pistacia integerrima (P. integerrina) insect galls are widely used in ayurveda and siddha system of medicine as karkatasringi. The use of leaf galls as a rejuvenator may be attributed to antioxidant property, however there is less scientific evidence. Therefore, the aim of this study was to evaluate the chemical composition and the antioxidant potential of leaf gall extracts (aqueous and ethanol) of P. integerrina, which is extensively used in the preparation of traditional medications. The antioxidant activities of aqueous and ethanolic leaf gall extracts were examined using diphenylpicrylhydrazyl (DPPH), hydroxyl scavenging and ferric reducing power (FRAP) methods. The presences of phenolics, tannins, phytosterols, triterpenoids, saponins, flavonoids and reducing sugars were identified in both the extracts. In comparison to the aqueous extract, the ethanolic extract had the highest total phenolic and flavonoid content at 234 ±2.4 mg of GAE/g d.w. and 95.5 ±3.2 mg of QUE/g d.w., respectively. This higher content of total phenolics and flavonoids found in the ethanolic extract was directly associated with higher antioxidant activity. This study demonstrates the poetnet antioxidant activities of P. integerrima leaf gall extracts. Further, there was a strong association between the higher antioxidant activities with that of higher total phenolic and flavonoid content in the ethanolic leaf gall extracts of P. integerrima. The results encourage the use of P. integerrima leaf gall extracts for medicinal health, functional food and nutraceuticals applications, due to their antioxidant properties. Future work will be interesting to learn the chemical composition and better understand the mechanism of action of the antioxidants present in the extract for development as a drug for therapeutic application.

Influence of Various Phenolic Compounds on Properties of Gelatin Film Prepared from Horse Mackerel Trachurus japonicus Scales.

PubMed

Le, Thuy; Maki, Hiroki; Okazaki, Emiko; Osako, Kazufumi; Takahashi, Kigen

2018-06-15

Influence of various phenolic compounds on physical properties and antioxidant activity of gelatin film from horse mackerel Trachurus japonicus scales was investigated. Tensile strength (TS) of the film was enhanced whereas elongation at break was declined by adding 1% to 5% phenolic compounds. Rutin was the most effective to improve the TS compared to the other tested phenolic compounds including ferulic acid, caffeic acid, gallic acid, and catechin. Gelatin films with the phenolic compounds showed the excellent UV barrier properties. FTIR spectra exhibited that wavenumber of amide-A band of films decreased with formation of hydrogen bonding between amino groups of gelatin and hydroxyl groups of the phenolic compounds. Gelatin film incorporated with rutin which has the largest number of hydroxyl groups among the tested compounds demonstrated the lowest wavenumber for the amide-A peak. It is indicated that hydroxyl groups contained in the phenolic compounds contribute to formation of hydrogen bonds involved in improvement of the mechanical properties of the films. The incorporation of the phenolic compounds with gelatin films also led to the increasing of total phenolic contents and DPPH radical scavenging activities. Thus, it is concluded that phenolic compounds can promote the quality of gelatin film. Properties of gelatin film derived from horse mackerel scales can be improved by adding of phenolic compounds. Phenolic compounds containing a large number of hydroxyl groups should be selected to enhance physical properties of the gelatin film. A biodegradable film prepared from horse mackerel gelatin incorporated with phenolic compounds, which has good physical properties and antioxidant properties, can solve environmental problems caused by synthetic plastic materials. © 2018 Institute of Food Technologists®.

Integrated Biorefining: Coproduction of Renewable Resol Biopolymer for Aqueous Stream Valorization

DOE PAGES

Wilson, A. Nolan; Price, Mariel J.; Mukarakate, Calvin; ...

2017-07-13

Phenol-formaldehyde resins are major material classes that are used in a range of applications including composites, adhesives, foams, electronics, and insulation. While efforts have been made to produce renewable resins, there has yet to be an approach that offers potential for economic viability and meets all critical quality metrics. This failure can be attributed largely to the use of phenol and cresol homologues and to high separation costs. In this work, the use of phenol, cresol, and alkyl phenols derived from the aqueous phase generated from catalytic fast pyrolysis of biomass to produce a high-quality biobased resin is demonstrated. Production,more » through catalytic fast pyrolysis (CFP), separation, through distillation and adsorption unit operations, and synthesis, through typical resol chemistry, produced a resin with properties, such as curing kinetics and molecular weight, competitive with petroleum-derived resin. In conclusion, this work explores a pathway to value-added coproducts from a CFP waste stream, which has the potential to improve the economic viability of biofuels production.« less

Integrated Biorefining: Coproduction of Renewable Resol Biopolymer for Aqueous Stream Valorization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wilson, A. Nolan; Price, Mariel J.; Mukarakate, Calvin

Phenol-formaldehyde resins are major material classes that are used in a range of applications including composites, adhesives, foams, electronics, and insulation. While efforts have been made to produce renewable resins, there has yet to be an approach that offers potential for economic viability and meets all critical quality metrics. This failure can be attributed largely to the use of phenol and cresol homologues and to high separation costs. In this work, the use of phenol, cresol, and alkyl phenols derived from the aqueous phase generated from catalytic fast pyrolysis of biomass to produce a high-quality biobased resin is demonstrated. Production,more » through catalytic fast pyrolysis (CFP), separation, through distillation and adsorption unit operations, and synthesis, through typical resol chemistry, produced a resin with properties, such as curing kinetics and molecular weight, competitive with petroleum-derived resin. In conclusion, this work explores a pathway to value-added coproducts from a CFP waste stream, which has the potential to improve the economic viability of biofuels production.« less

Effects of nitrogen fertilization on the phenolic composition and antioxidant properties of basil (Ocimum basilicum L.).

PubMed

Nguyen, Phuong M; Niemeyer, Emily D

2008-09-24

Many herbs and spices have been shown to contain high levels of polyphenolic compounds with potent antioxidant properties. In the present study, we explore how nutrient availability, specifically nitrogen fertilization, affects the production of polyphenolic compounds in three cultivars (Dark Opal, Genovese, and Sweet Thai) of the culinary herb, basil ( Ocimum basilicum L.). Nitrogen fertilization was found to have a significant effect on total phenolic levels in Dark Opal ( p < 0.001) and Genovese ( p < 0.001) basil with statistically higher phenolic contents observed when nutrient availability was limited at the lowest (0.1 mM) applied nitrogen treatment. Similarly, basil treated at the lowest nitrogen fertilization level generally contained significantly higher rosmarinic ( p = 0.001) and caffeic ( p = 0.001) acid concentrations than basil treated at other nitrogen levels. Nitrogen fertilization also affected antioxidant activity ( p = 0.002) with basil treated at the highest applied nitrogen level, 5.0 mM, exhibiting lower antioxidant activity than all other nitrogen treatments. The anthocyanin content of Dark Opal basil was not affected by applied nitrogen level, but anthocyanin concentrations were significantly impacted by growing season ( p = 0.001). Basil cultivar was also determined to have a statistically significant effect on total phenolic levels, rosmarinic and caffeic acid concentrations, and antioxidant activities.

From Olive Fruits to Olive Oil: Phenolic Compound Transfer in Six Different Olive Cultivars Grown under the Same Agronomical Conditions.

PubMed

Talhaoui, Nassima; Gómez-Caravaca, Ana María; León, Lorenzo; De la Rosa, Raúl; Fernández-Gutiérrez, Alberto; Segura-Carretero, Antonio

2016-03-04

Phenolic compounds are responsible of the nutritional and sensory quality of extra-virgin olive oil (EVOO). The composition of phenolic compounds in EVOO is related to the initial content of phenolic compounds in the olive-fruit tissues and the activity of enzymes acting on these compounds during the industrial process to produce the oil. In this work, the phenolic composition was studied in six major cultivars grown in the same orchard under the same agronomical and environmental conditions in an effort to test the effects of cultivars on phenolic composition in fruits and oils as well as on transfer between matrices. The phenolic fractions were identified and quantified using high-performance liquid chromatography-diode array detector-time-of-flight-mass spectrometry. A total of 33 phenolic compounds were determined in the fruit samples and a total of 20 compounds in their corresponding oils. Qualitative and quantitative differences in phenolic composition were found among cultivars in both matrices, as well as regarding the transfer rate of phenolic compounds from fruits to oil. The results also varied according to the different phenolic groups evaluated, with secoiridoids registering the highest transfer rates from fruits to oils. Moreover, wide-ranging differences have been noticed between cultivars for the transfer rates of secoiridoids (4.36%-65.63% of total transfer rate) and for flavonoids (0.18%-0.67% of total transfer rate). 'Picual' was the cultivar that transferred secoiridoids to oil at the highest rate, whereas 'Changlot Real' was the cultivar that transferred flavonoids at the highest rates instead. Principal-component analysis confirmed a strong genetic effect on the basis of the phenolic profile both in the olive fruits and in the oils.

Phenolic composition of pomegranate peel extracts using an LC-MS approach with silica hydride columns

USDA-ARS?s Scientific Manuscript database

The peels of different pomegranate cultivars (Molla Nepes, Parfianka, Purple Heart, Wonderful and Vkunsyi) were compared in terms of phenolic composition and total phenolics. Analyses were performed on two silica hydride-based stationary phases: phenyl and undecenoic acid columns. Quantitation was ...

Anthocyanins, antioxidative, and antimicrobial properties of American cranberry (Vaccinium macrocarpon Ait.) and their press cakes.

PubMed

Viskelis, P; Rubinskiene, M; Jasutiene, I; Sarkinas, A; Daubaras, R; Cesoniene, L

2009-03-01

Amounts of total phenolics, anthocyanins, and ascorbic acid in 4 American cranberry varieties harvested at 4 stages of maturity were measured. The larger amount of phenolic compounds was found in berries of "Black Veil" cultivar (504 mg/100 g) at II stage of maturity. Significantly larger amounts of anthocyanins were determined in the overripe berries of the cultivars "Ben Lear" and "Black Veil." The amount of ascorbic acid in berries increased during ripening from I to III stage, and slightly decreased in the overripe berries. The biggest quantities of ascorbic acid were found in the ripe berries of "Ben Lear" cultivar (15.8 mg/100 g). The distribution of anthocyanins pigments was determined by HPLC-UV/MS in mature berries. The composition of individual anthocyanins in berries was quite similar in all the studied cranberry cultivars. While skins of cranberries are rich in anthocyanins and other phenolic compounds, the extracts of the by-products of cranberries juice-berry cakes, were analyzed and obtained results were compared with the properties of extracts made from whole berries. The anthocyanins and total phenolics content, radical scavenging activity, antimicrobial activity of the whole berries, and their press cakes extracts were measured. All investigated extracts from berries and their press cakes showed good radical scavenging activity and revealed antimicrobial properties. It was found that Bacillus cereus (ATCC 10876) and Micrococcus luteus (ATCC 9341) were the most sensitive among 10 tested Gram-negative and Gram-positive bacteria.

A composite system approach to aircraft cabin fire safety

NASA Technical Reports Server (NTRS)

Kourtides, D. A.; Parker, J. A.; Gilwee, W. J., Jr.; Lerner, N. R.; Hilado, C. J.; Labossiere, L. A.; Hsu, M.-T.

1976-01-01

The thermochemical and flammability characteristics of two polymeric composites currently in use and seven others being considered for use as aircraft interior panels are described. The properties studied included: (1) limiting oxygen index of the composite constituents; (2) fire containment capability of the composite; (3) smoke evolution from the composite; (4) thermogravimetric analysis; (5) composition of the volatile products of thermal degradation; and (6) relative toxicity of the volatile products of pyrolysis. The performance of high-temperature laminating resins such as bismaleimides is compared with the performance of phenolics and epoxies. The relationship of increased fire safety with the use of polymers with high anaerobic char yield is shown. Processing parameters of one of the bismaleimide composites is detailed.

A composite system approach to aircraft cabin fire safety

NASA Technical Reports Server (NTRS)

Kourtides, D. A.; Parker, J. A.; Gilwee, W. J., Jr.; Lerner, N. R.; Hilado, C. J.; Labossiere, L. A.; Hsu, M. T. S.

1976-01-01

The thermochemical and flammability characteristics of two polymeric composites currently in use and seven others being considered for use as aircraft interior panels are described. The properties studied included: (1) limiting oxygen index of the composite constituents; (2) fire containment capability of the composite; (3) smoke evolution from the composite; (4) thermogravimetric analysis; (5) composition of the volatile products of thermal degradation; and (6) relative toxicity of the volatile products of pyrolysis. The performance of high temperature laminating resins such as bismaleimides is compared with the performance of phenolics and epoxies. The relationship of increased fire safety with the use of polymers with high anaerobic char yield is shown. Processing parameters of one of the baremaleimide composites are detailed.

Anti-oxidant properties and polyphenolic profile screening of Vitis vinifera stems and leaves crude extracts grown in Perlis, Malaysia

NASA Astrophysics Data System (ADS)

Zakaria, Nursyahda; Zulkifli, Razauden Mohamed; Akhir, Fazrena Nadia Md; Basar, Norazah

2014-03-01

Grape has become a fast growing agricultural sector in Malaysia producing between 0.62 kg to 2.03 kg waste per vinestock. This study aims to generate useful information on anti-oxidative properties as well as polyphenolic composition of grapevine waste. Stems and leaves of Vitis vinifera cultivated in Perlis, Malaysia were extracted using methanol, ethyl acetate and petroleum ether. Ethyl acetate stems extract exhibited highest total phenolic content. While in DPPH assay, methanolic stems extract show the highest antioxidant activities. This result indicates that total phenolic content in the extracts may not contribute directly to the antioxidant activities. Thin Layer Chromatograms of all crude extracts exhibited good separation under solvent system petroleum ether-ethyl acetate (2:3) resulted in detection of resveratrol in ethyl acetate stems crude extract.

Novel high-strength biocomposites based on microfibrillated cellulose having nano-order-unit web-like network structure

NASA Astrophysics Data System (ADS)

Nakagaito, A. N.; Yano, H.

2005-01-01

A completely new kind of high-strength composite was manufactured using microfibrillated cellulose (MFC) derived from kraft pulp. Because of the unique structure of nano-order-scale interconnected fibrils and microfibrils greatly expanded in the surface area that characterizes MFC, it was possible to produce composites that exploit the extremely high strength of microfibrils. The Young’s modulus (E) and bending strength (σb) of composites using phenolic resin as binder achieved values up to 19 GPa and 370 MPa, respectively, with a density of 1.45 g/cm2, exhibiting outstanding mechanical properties for a plant-fiber-based composite.

Free and Bound Phenolic Compound Content and Antioxidant Activity of Different Cultivated Blue Highland Barley Varieties from the Qinghai-Tibet Plateau.

PubMed

Yang, Xi-Juan; Dang, Bin; Fan, Ming-Tao

2018-04-11

In this study, the polyphenols composition and antioxidant properties of 12 blue highland barley varieties planted on the Qinghai-Tibet Plateau area were measured. The contents of the free, bound and total phenolic acids varied between 166.20-237.60, 170.10-240.75 and 336.29-453.94 mg of gallic acid equivalents per 100 g of dry weight (DW) blue highland barley grains, while the free and bound phenolic acids accounted for 50.09% and 49.91% of the total phenolic acids, respectively. The contents of the free, bound and total flavones varied among 20.61-25.59, 14.91-22.38 and 37.91-47.98 mg of catechin equivalents per 100 g of dry weight (DW) of blue highland barley grains, while the free and bound flavones accounted for 55.90% and 44.10% of the total flavones, respectively. The prominent phenolic compounds in the blue hulless barley grains were gallic acid, benzoic acid, syringic acid, 4-coumaric acid, naringenin, hesperidin, rutin, (+)-catechin and quercetin. Among these, protocatechuic acid, chlorogenic acid and (+)-catechin were the major phenolic compounds in the free phenolics extract. The most abundant bound phenolics were gallic acid, benzoic acid, syringic acid, 4-coumaric acid, benzoic acid, dimethoxybenzoic acid, naringenin, hesperidin, quercetin and rutin. The average contribution of the bound phenolic extract to the DPPH • free radical scavenging capacity was higher than 86%, that of free phenolic extract to the ABTS •+ free radical scavenging capacity was higher than 79%, and that of free phenolic (53%) to the FRAP antioxidant activity was equivalent to that of the bound phenol extract (47%). In addition, the planting environment exerts a very important influence on the polyphenol composition, content and antioxidant activity of blue highland barley. The correlation analysis showed that 2,4-hydroxybenzoic acid and protocatechuic acid were the main contributors to the DPPH • and ABTS •+ free radical scavenging capacity in the free phenolic extract, while chlorogenic acid, vanillic acid, ferulic acid and quercetin were the main contributors to the free radical scavenging capacity in the bound phenol extract. The study results show that the blue highland barley grains have rich phenolic compounds and high antioxidant activity, as well as significant varietal differences. The free and bound phenolic extracts in the blue hulless barley grains have an equivalent proportion in the total phenol, and co-exist in two forms. They can be used as a potential valuable source of natural antioxidants, and can aid in enhancing the development and daily consumption of foods relating to blue highland barley.

Influence of vacuum drying temperature on: physico-chemical composition and antioxidant properties of murta berries

USDA-ARS?s Scientific Manuscript database

Murta (Ugni molinae T.) berries were vacuum dried at a constant pressure of 15 kPa. The effects of processing temperatures (50, 60, 70, 80 and 90 °C) on the physico-chemical characteristics, the phenolic and flavonoid compounds, the antioxidant activity (measured by DPPH and ORAC) and the sugar and ...

USSR Report, Chemistry

DTIC Science & Technology

1987-03-17

conductivity with respect to silver, copper, fluorine and hydrogen ions, selection of the chemical composition and type of crystalline structure...distillates. It was found that residual petroleum asphalt, NKG demulsifier and "neftegaz-4" varnish oil improved the rheological properties and decreased...mass loss, and accumulation of macromolecular fragments bearing substituted phenols, in order to determine criteria on which shelflife of varnish

Sorbus aucuparia and Sorbus aria as a Source of Antioxidant Phenolics, Tocopherols, and Pigments.

PubMed

Šavikin, Katarina P; Zdunić, Gordana M; Krstić-Milošević, Dijana B; Šircelj, Helena J; Stešević, Danijela D; Pljevljakušić, Dejan S

2017-12-01

Due to its nutritive and medicinal properties, berries of some Sorbus species are used for the preparation of jams and jelly as well as in traditional medicine. On the other hand, their chemical composition is not much studied especially of those grown in Balkan Peninsula. We have analyzed individual phenolics, tocopherols, carotenoids and chlorophylls using HPLC in berries from Sorbus aucuparia and Sorbus aria collected in different localities in Serbia and Montenegro together with the amounts of total phenolics and proanthocyanidins as well as their radical scavenging activity against DPPH radical. Berries of S. aucuparia were richer source of polyphenolics in comparision with S. aria and, regardless the species and locality, caffeoylquinic acids such as neochlorogenic and chlorogenic acid were the most abundant compounds. Among analyzed tocopherols the most abundant in all samples was α-tocopherol (0.48 - 19.85 μg/g dw) as it was β-carotene among carotenoids (mean concentration of 0.98 μg/g dw in S. aucuparia and 0.40 μg/g dw in S. aria, respectively). Correlation between total phenolics and DPPH radical scavenging activity was noticed. Our study represents comprehensive report on chemical composition of S. aucuparia and S. aria which could contribute to a better understanding of their quality. © 2017 Wiley-VHCA AG, Zurich, Switzerland.

Evaluation of phenolic composition, antioxidant, anti-inflammatory and anticancer activities of Polygonatum verticillatum (L.).

PubMed

Kumar Singh, Sandeep; Patra, Arjun

2018-04-18

Polygonatum verticillatum (L.) All. (Ruscaceae), one of the Ashtawarga plants, is widely used for treatment of various ailments. The present study was undertaken to determine the phenolic composition, antioxidant, anti-inflammatory and anticancer activities of several extracts (petroleum ether, dichloromethane, chloroform, ethanol, and aqueous) from the rhizomes of the plant. Coarsely powdered dry rhizome was successively extracted with different solvents of increasing polarity (petroleum ether, dichloromethane, chloroform, ethanol and water). The phenolic compositions, in terms of total phenolic content (TPC), total flavonoid content (TFC) and total condensed tannin content (TTC), were evaluated with the Folin-Ciocalteu assay, aluminum chloride colorimetric assay and vanillin spectrophotometric assay, respectively. Total antioxidant capacity, 1,1-diphenyl-2-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) assays were used to assess the antioxidant potential of each extract. A protein denaturation model and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay were used to evaluate in vitro anti-inflammatory and anticancer activities, respectively. Gas chromatography-mass spectrometry (GC/MS) analysis was carried out to demonstrate various phytoconstituents in each extract. Correlation studies were also performed between phenolic composition (TPC, TFC and TTC) and different biological activities. Ethanol extract showed maximum TPC (0.126 mg/g, gallic acid equivalent in dry sample), TFC (0.094 mg/g, rutin equivalent in dry sample) and TTC (29.32 mg/g, catechin equivalent in dry sample), as well as antioxidant and anti-inflammatory properties. Chloroform extract exhibited the strongest cytotoxicity against the human breast cancer cell line, MCF-7. GC/MS analysis revealed the presence of 90 different phytoconstituents among the extracts. Antioxidant and anti-inflammatory activities had a positive correlation with TPC, TFC and TTC. However, the anticancer activity showed a negative correlation with TPC, TFC and TTC. From the present study, it can be concluded that P. verticillatum possessed remarkable antioxidant, anti-inflammatory, and anticancer activities, which could be due to different secondary metabolites of the plant. Phenolic compounds are likely responsible for antioxidant and anti-inflammatory activities. However, flavonoids and other compounds might contribute to the anticancer potential of the plant. Copyright © 2018 Shanghai Changhai Hospital. Published by Elsevier B.V. All rights reserved.

The influence of beverage composition on delivery of phenolic compounds from coffee and tea.

PubMed

Ferruzzi, Mario G

2010-04-26

Epidemiological data suggest that consumption of coffee and tea is associated with a reduced risk of several chronic and degenerative diseases including cardiovascular disorders, diabetes, obesity and neurodegenerative disorders. Both coffee and tea are a rich source of phenolic compounds including chlorogenic acids in coffee; and flavan-3-ols as well as complex theaflavins and thearubigens in tea. Coffee and tea are two of the most commonly consumed beverages in the world and thus represent a significant opportunity to positively affect disease risk and outcomes globally. Central to this opportunity is a need to better understand factors that may affect the bioavailability of specific phenolic components from coffee and tea based beverages. An overview of the phenolic composition of coffee and tea is discussed in the context of how processing and composition might influence phenolic profiles and bioavailability of individual phenolic components. Specifically, the impact of beverage formulation, the extent and type of processing and the influence of digestion on stability, bioavailability and metabolism of bioactive phenolics from tea and coffee are discussed. The impact of co-formulation with ascorbic acid and other phytochemicals are discussed as strategies to improve absorption of these health promoting phytochemicals. A better understanding of how the beverage composition impacts phenolic profiles and their bioavailability is critical to development of beverage products designed to deliver specific health benefits. Copyright 2010 Elsevier Inc. All rights reserved.

Antioxidant properties, physico-chemical characteristics and proximate composition of five wild fruits of Manipur, India.

PubMed

Sharma, Ph Baleshwor; Handique, Pratap Jyoti; Devi, Huidrom Sunitibala

2015-02-01

Antioxidant properties, physico-chemical characteristics and proximate composition of five wild fruits viz., Garcinia pedunculata, Garcinia xanthochymus, Docynia indica, Rhus semialata and Averrhoa carambola grown in Manipur, India were presented in the current study. The order of the antioxidant activity and reducing power of the fruit samples was found as R. semialata > D. indica > G. xanthochymus > A. carambola > G. pedunculata. Good correlation coefficient (R(2) > 0.99) was found among the three methods applied to determine antioxidant activity. Total phenolic content was positively correlated (R(2) = 0.960) with the antioxidant activity however, total flavonoid content was not positively correlated with the antioxidant activity. Physico-chemical and proximate composition of these fruits is documented for the first time.

Phenolic composition, antioxidant capacity and antibacterial activity of selected Irish Brassica vegetables.

PubMed

Jaiswal, Amit Kumar; Rajauria, Gaurav; Abu-Ghannam, Nissreen; Gupta, Shilpi

2011-09-01

Vegetables belonging to the Brassicaceae family are rich in polyphenols, flavonoids and glucosinolates, and their hydrolysis products, which may have antibacterial, antioxidant and anticancer properties. In the present study, phenolic composition, antibacterial activity and antioxidant capacity of selected Brassica vegetables, including York cabbage, Brussels sprouts, broccoli and white cabbage were evaluated after extraction with aqueous methanol. Results obtained showed that York cabbage extract had the highest total phenolic content, which was 33.5, followed by 23.6, 20.4 and 18.4 mg GAE/g of dried weight (dw) of the extracts for broccoli, Brussels sprouts and white cabbage, respectively. All the vegetable extracts had high flavonoid contents in the order of 21.7, 17.5, 15.4 and 8.75 mg QE/g of extract (dw) for York cabbage, broccoli, Brussels sprouts and white cabbage, respectively. HPLC-DAD analysis showed that different vegetables contain a mixture of distinct groups of phenolic compounds. All the extracts studied showed a rapid and concentration dependent antioxidant capacity in diverse antioxidant systems. The antibacterial activity was determined against Gram-positive and Gram-negative bacteria. York cabbage extract exhibited significantly higher antibacterial activity against Listeria monocytogenes (100%) and Salmonella abony (94.3%), being the most susceptible at a concentration of 2.8%, whereas broccoli, Brussels sprouts and white cabbage had moderate to weak activity against all the test organisms. Good correlation (r2 0.97) was found between total phenolic content obtained by spectrophotometric analysis and the sum of the individual polyphenols monitored by HPLC-DAD.

Phenolic composition profiling of different edible parts and by-products of date palm (Phoenix dactylifera L.) by using HPLC-DAD-ESI/MSn.

PubMed

Abu-Reidah, Ibrahim M; Gil-Izquierdo, Ángel; Medina, Sonia; Ferreres, Federico

2017-10-01

Fruits and vegetables are an important source of dietary antioxidants and epidemiological studies show that their regular intake in the diet may decrease the risk of several chronic diseases. Phoenix dactylifera L. (date palm or dates) is an important crop, widely used in the Arabian region and in other parts of the world as a food and also in folk medicine, due to its health-promoting properties. Antioxidant phytochemicals present in plant foods are partly responsible for such health benefits. The antioxidants present in dates are mainly phenolics, like flavonoids and phenolic acids. The fruits of dates have been widely studied with regard to their phenolic composition. However, few studies are available in the bibliography regarding other, non-edible parts of the date palm tree. In this context, in the present work the phenolic components of different parts of P. dactylifera (cv. Medjool or Mejhool) - namely, fruit pulp and skin, fronds (leaves), clusters, and pollen - have been investigated using HPLC-DAD-ESI/MS n in the negative ionization mode. The overall analysis of the phenolic compounds revealed that there was a qualitative similarity among the different dates parts analyzed. The method used provided tentative identification of 52 compounds: mainly flavonoid glycosides of quercetin, luteolin, apigenin, chrysoeriol, kaempferol, isorhamnetin, 3-methyl-isorhamnetin, sulfates, and malonyl derivatives. In the present work, more than 30 phenolic derivatives are described for the first time in dates. To the best of our knowledge, kaempferol glycosides and malonyl derivatives have not been described previously in P. dactylifera. The results highlight the importance of P. dactylifera L. as a promising source of functional ingredients and boost its potential use in the food and nutraceutical industries. The MS data, MS n fragmentation pattern, and UV information obtained have been of great help in the interpretation of the compounds detected and in their structural identification. Copyright © 2016 Elsevier Ltd. All rights reserved.

Development and Optimisation of an HPLC-DAD-ESI-Q-ToF Method for the Determination of Phenolic Acids and Derivatives

PubMed Central

Restivo, Annalaura; Degano, Ilaria; Ribechini, Erika; Colombini, Maria Perla

2014-01-01

A method for the HPLC-MS/MS analysis of phenols, including phenolic acids and naphtoquinones, using an amide-embedded phase column was developed and compared to the literature methods based on classical C18 stationary phase columns. RP-Amide is a recently developed polar embedded stationary phase, whose wetting properties mean that up to 100% water can be used as an eluent. The increased retention and selectivity for polar compounds and the possibility of working in 100% water conditions make this column particularly interesting for the HPLC analysis of phenolic acids and derivatives. In this study, the chromatographic separation was optimised on an HPLC-DAD, and was used to separate 13 standard phenolic acids and derivatives. The method was validated on an HPLC-ESI-Q-ToF. The acquisition was performed in negative polarity and MS/MS target mode. Ionisation conditions and acquisition parameters for the Q-ToF detector were investigated by working on collision energies and fragmentor potentials. The performance of the method was fully evaluated on standards. Moreover, several raw materials containing phenols were analysed: walnut, gall, wine, malbec grape, French oak, red henna and propolis. Our method allowed us to characterize the phenolic composition in a wide range of matrices and to highlight possible matrix effects. PMID:24551158

Comparison on phenolic compounds and antioxidant properties of cabernet sauvignon and merlot wines from four wine grape-growing regions in China.

PubMed

Jiang, Bao; Zhang, Zhen-Wen

2012-07-25

The antioxidant activities in the Cabernet Sauvignon and Merlot wines from four wine grape-growing regions in China were measured by different analytical assays: 2,2-diphenyl-1-picrylhydrazyl (DPPH·), cupric reducing antioxidant capacity (CUPRAC), superoxide radical-scavenging activity (SRSA) and the contents of total phenols, total flavonoids, total flavanols and total anthocyanins were determined. The results showed that the contents of phenolic compounds and the levels of antioxidant activity in the wine samples greatly varied with cultivar and environmental factors of vine growth. The contents of phenolic compounds and antioxidant activities in Cabernet Sauvignon and Merlot wines from the Yuquanying region of Ningxia were significantly higher than other three regions, followed by the wines from Shacheng region of Hebei, and these parameters were the lowest in Cabernet Sauvignon and Merlot wines from the Changli regions of Hebei and Xiangning region of Shanxi. Taken together, a close relationship between phenolic subclasses and antioxidant activity was observed for the wine samples. Moreover, there were significant discrepancies in the individual phenolic composition and content of four regional Cabernet Sauvignon and Merlot wines, among which the individual phenolic compounds (catechin, epicatechin, cinnamic acid, quercetin-3-O-glucuronide, quercetin-3-O-glucoside, laricitrin-3-O-glucoside and isorhamnetin-3-O-glucoside) revealed a significant correlation (p < 0.05) with the antioxidant capacity in present study, especially for catechin and epicatechin.

Materials research for aircraft fire safety

NASA Technical Reports Server (NTRS)

Kourtides, D. A.; Parker, J. A.; Bricker, R. W.

1976-01-01

The thermochemical and flammability characteristics of two polymeric composites currently in use and seven others being considered for use as aircraft interior panels are described. The properties studied included: (1) limiting oxygen index of the composite constituents; (2) fire containment capability of the composite; (3) smoke evolution from the composite; (4) thermogravimetric analysis; (5) composition of the volatile products of thermal degradation; and (6) relative toxicity of the volatile products of pyrolysis. The performance of high-temperature laminating resins such as bismaleimides is compared with the performance of phenolics and epoxies. The relationship of increased fire safety with the use of polymers with high anaerobic char yield is shown. Processing parameters of the state-of-the-art and the advanced bismaleimide composites are detailed.

High-Temperature Graphite/Phenolic Composite

NASA Technical Reports Server (NTRS)

Seal, Ellis C.; Bodepudi, Venu P.; Biggs, Robert W., Jr.; Cranston, John A.

1995-01-01

Graphite-fiber/phenolic-resin composite material retains relatively high strength and modulus of elasticity at temperatures as high as 1,000 degrees F. Costs only 5 to 20 percent as much as refractory materials. Fabrication composite includes curing process in which application of full autoclave pressure delayed until after phenolic resin gels. Curing process allows moisture to escape, so when composite subsequently heated in service, much less expansion of absorbed moisture and much less tendency toward delamination. Developed for nose cone of external fuel tank of Space Shuttle. Other potential aerospace applications for material include leading edges, parts of nozzles, parts of aircraft engines, and heat shields. Terrestrial and aerospace applications include structural firewalls and secondary structures in aircraft, spacecraft, and ships. Modified curing process adapted to composites of phenolic with other fiber reinforcements like glass or quartz. Useful as high-temperature circuit boards and electrical insulators.

Augmentation of chemical and organoleptic properties in Syzygium cumini wine by incorporation of grape seeds during vinification.

PubMed

VenuGopal, K S; Cherita, Chris; Anu-Appaiah, K A

2018-03-01

The role of grape seed tannins on improving organoleptic properties and its involvement in color stabilization in red wine are well established. The addition of grape seeds as the source of condensed tannins in fruit wine may provide a solution for its color instability and improvement of sensory attributes. Syzgium cumini is traditionally known for its therapeutic properties. In the current study, the influence of yeasts and grape seed addition during fermentation on the chromatic, phenolic and sensory attributes of the wine was accessed. Grape seed addition improved the color characteristics of wine and increased overall phenolic composition. Analysis by HPLC revealed 6 major anthocyanins, among which 3, 5-diglucoside form of delphidin and petunidin was found to be the major components. Cluster and PLSR analysis explained the impact of seed addition on the yeasts, as well as on the perception of panelists, with bitterness and astringency as the dominating attributes. Copyright © 2017 Elsevier Ltd. All rights reserved.

Ablation and Thermal Response Property Model Validation for Phenolic Impregnated Carbon Ablator

NASA Technical Reports Server (NTRS)

Milos, F. S.; Chen, Y.-K.

2009-01-01

Phenolic Impregnated Carbon Ablator was the heatshield material for the Stardust probe and is also a candidate heatshield material for the Orion Crew Module. As part of the heatshield qualification for Orion, physical and thermal properties were measured for newly manufactured material, included emissivity, heat capacity, thermal conductivity, elemental composition, and thermal decomposition rates. Based on these properties, an ablation and thermal-response model was developed for temperatures up to 3500 K and pressures up to 100 kPa. The model includes orthotropic and pressure-dependent thermal conductivity. In this work, model validation is accomplished by comparison of predictions with data from many arcjet tests conducted over a range of stagnation heat flux and pressure from 107 Watts per square centimeter at 2.3 kPa to 1100 Watts per square centimeter at 84 kPa. Over the entire range of test conditions, model predictions compare well with measured recession, maximum surface temperatures, and in depth temperatures.

Effect of inert gas and prefermentative treatment with polyvinylpolypyrrolidone on the phenolic composition of Chilean Sauvignon blanc wines.

PubMed

Cáceres-Mella, Alejandro; Peña-Neira, Álvaro; Parraguez, Jenny; López-Solís, Remigio; Laurie, V Felipe; Canals, Joan Miquel

2013-06-01

Sauvignon blanc wines are produced under a wide variety of winemaking conditions, some of which include different fruit-ripening levels, cold soaks and the use of fining agents and inert gases. Anecdotal evidence suggests that sensory variations among these wines may have to do with their phenolic composition and concentration. Therefore the aim of this work was to study the effects of different winemaking conditions typically used in Chile on the phenolic composition and concentration of Sauvignon blanc wines. The use of an inert gas (CO2) in winemaking produced differences in the proportion of proanthocyanidin fractions. A higher concentration of flavan-3-ol monomers resulted from winemaking in the presence of inert gas. This condition also produced a higher content of total phenols and low-molecular-weight phenolic compounds. Low doses of polyvinylpolypyrrolidone (PVPP) in the prefermentative treatments produced wines with a higher content of phenolic compounds. Under these conditions a higher content of polymeric proanthocyanidins was observed. Different winemaking conditions modified the concentration and proportion of proanthocyanidin fractions and the global phenolic composition of the resulting white wines. This should be taken into account by the wineries producing these wines. © 2012 Society of Chemical Industry.

Antioxidant and antimicrobial activity of natural phenolic extract from defatted soybean flour by-product for stone fruit postharvest application.

PubMed

Villalobos, María del Carmen; Serradilla, Manuel Joaquín; Martín, Alberto; Ordiales, Elena; Ruiz-Moyano, Santiago; Córdoba, María de Guía

2016-04-01

Fresh fruit is highly perishable during storage and transport, so there has been growing interest in finding safe and natural antimicrobial compounds as a control tool. Phenolic compounds are secondary metabolites naturally present in vegetable material and have been associated with antimicrobial and antioxidant properties. Therefore, the aim of this study was to investigate the antioxidant capacity and potential antimicrobial effect of phenolic extract obtained from defatted soybean flour against selected pathogenic bacteria and microorganisms responsible of fruit decay. Analysis of phenolic composition by HPLC-MS showed the presence of a wide range of compounds, with isoflavones and phenolic acids the main polyphenols identified. Furthermore, the phenolic extract had important antioxidant activity by two different assays. Related to antimicrobial activity, in vitro experiments demonstrated that phenolic extract displayed a high activity against the main foodborne pathogens, while a moderate inhibition was found against five spoilage yeasts and Monilia laxa and a scarce effect for Penicillium glabrum, Cladosporium uredinicola and Botrytis cinerea. Interestingly these compounds considerably inhibited the mycelial growth of Monilia laxa, in both in vitro and in vivo experiments. The results of the present study revealed that defatted soybean flour is an important source of phenolic compounds with remarkable antimicrobial and antioxidant activity, suggesting the possibility of using them as natural additives in postharvest treatments to extend the shelf life of fruit. © 2015 Society of Chemical Industry.

Dynamic response of phenolic resin and its carbon-nanotube composites to shock wave loading

DOE PAGES

Arman, B.; An, Q.; Luo, S. N.; ...

2011-01-04

We investigate with nonreactive molecular dynamics simulations the dynamic response of phenolic resin and its carbon-nanotube (CNT) composites to shock wave compression. For phenolic resin, our simulations yield shock states in agreement with experiments on similar polymers except the “phase change” observed in experiments, indicating that such phase change is chemical in nature. The elastic–plastic transition is characterized by shear stress relaxation and atomic-level slip, and phenolic resin shows strong strain hardening. Shock loading of the CNT-resin composites is applied parallel or perpendicular to the CNT axis, and the composites demonstrate anisotropy in wave propagation, yield and CNT deformation. Themore » CNTs induce stress concentrations in the composites and may increase the yield strength. Our simulations indicate that the bulk shock response of the composites depends on the volume fraction, length ratio, impact cross-section, and geometry of the CNT components; the short CNTs in current simulations have insignificant effect on the bulk response of resin polymer.« less

Functional and technological potential of dehydrated Phaseolus vulgaris L. flours.

PubMed

Ramírez-Jiménez, A K; Reynoso-Camacho, R; Mendoza-Díaz, S; Loarca-Piña, G

2014-10-15

The effect of cooking followed by dehydration was evaluated on the bioactive composition, antioxidant activity and technological properties of two varieties (Negro 8025 and Bayo Madero) of common beans. Quercetin, rutin, and phenolic acids were the most abundant phenolics found. Cooking processes resulted in decreased values of some phenolic compounds and antioxidant capacity. A subsequent dehydration increased TEAC values, resistant starch content and decreased starch digestibility. Oligosaccharides and dietary fibre were preserved in both treatments. Variety had a strong impact on phytochemical profile, being Negro 8025 that exhibited the highest content of most of the compounds assessed. Water absorption index (WAI) and oil absorption capacity (OAC) were determined in order to measure technological suitability. Dehydration produced flours with stable WAI and low oil pick up. The results suggest that the flours of Negro 8025 beans have a good potential to be considered as functional ingredient for healthy food products. Copyright © 2014 Elsevier Ltd. All rights reserved.

Mechanical Characterization of Composites and Foams for Aerospace Applications

NASA Technical Reports Server (NTRS)

Veazie, D. R.; Glinsey, C.; Webb, M. M.; Norman, M.; Meador, Michael A. (Technical Monitor)

2000-01-01

Experimental studies to investigate the mechanical properties of ultra-lightweight polyimide foams for space applications, compression after impact (CAI) properties for low velocity impact of sandwich composites, and aspen fiber/polypropylene composites containing an interface adhesive additive, Maleic Anhydride Grafted Polypropylene (MAPP), were performed at Clark Atlanta University. Tensile, compression, flexural, and shear modulus tests were performed on TEEK foams categorized by their densities and relative cost according to ASTM specifications. Results showed that the mechanical properties of the foams increased as a function of higher price and increasing density. The CAI properties of Nomex/phenolic honeycomb core, fiberglass/epoxy facesheet sandwich composites for two damage arrangements were compared using different levels of impact energy ranging from 0 - 452 Joules. Impact on the thin side showed slightly more retention of CAI strength at low impact levels, whereas higher residual compressive strength was observed from impact on the thick side at higher impact levels. The aspen fiber/polypropylene composites studied are composed of various percentages (by weight) of aspen fiber and polypropylene ranging from 30%-60% and 40%-100%, respectively. Results showed that the MAPP increases tensile and flexural strength, while having no significant influence on tensile and flexural modulus.

Evolution of the localisation and composition of phenolics in grape skin between veraison and maturity in relation to water availability and some climatic conditions.

PubMed

Cadot, Yves; Chevalier, Michel; Barbeau, Gerard

2011-08-30

Several studies have investigated the composition of phenolics in grape skin during grape maturation under various conditions of light exposure, water stress, nitrogen supply and mineral nutrition, but their localisation during berry development is not well known. In this study the composition and localisation of proanthocyanidins were monitored for three years on four plots known to induce a distinctive behaviour of the vine (Cabernet Franc). The composition of phenolics was determined by spectrophotometry; also, in one year, proanthocyanidins were determined by high-performance liquid chromatography. Further information was obtained histochemically by means of toluidine blue O staining and image analysis. The results indicated that clear differences in phenolic quantification existed between the biochemical and histochemical approaches; the proportion of cells without phenolics was not linked with the quantity determined by the analytical methods used. The histochemical method showed the evolution of the localisation and typology of cells with and without phenolics during ripening. The number of cells without any phenolic compounds appeared to be very dependent on the mesoclimatic conditions and only slightly dependent on the site water status. Clear differences in phenolic quantification existed between the biochemical and histochemical approaches; the proportion of cells with phenolics was not linked with the quantity determined by biochemistry. The histochemical method showed an evolution of the localisation and typology of cells with and without phenolics in which mesoclimatic conditions were the most influential factor. Finally, the study showed some advantages of the histochemical approach: it gives information about the anatomy of the tissue as well as the nature and distribution of some of the large macromolecules and allows reconstruction of the three-dimensional plant structure. Copyright © 2011 Society of Chemical Industry.

Obtention and characterization of phenolic extracts from different cocoa sources.

PubMed

Ortega, Nàdia; Romero, Maria-Paz; Macià, Alba; Reguant, Jordi; Anglès, Neus; Morelló, José-Ramón; Motilva, Maria-Jose

2008-10-22

The aim of this study was to evaluate several cocoa sources to obtain a rich phenol extract for use as an ingredient in the food industry. Two types of phenolic extracts, complete and purified, from different cocoa sources (beans, nibs, liquor, and cocoa powder) were investigated. UPLC-MS/MS was used to identify and quantify the phenolic composition of the extracts, and the Folin-Ciocalteu and vanillin assays were used to determine the total phenolic and flavan-3-ol contents, respectively. The DPPH and ORAC assays were used to measure their antioxidant activity. The results of the analysis of the composition of the extracts revealed that the major fraction was procyanidins, followed by flavones and phenolic acids. From the obtained results, the nib could be considered the most interesting source for obtaining a rich phenolic cocoa extract because of its rich phenolic profile content and high antioxidant activity in comparison with the other cocoa sources.

Impact of adding white pomace to red grapes on the phenolic composition and color stability of Syrah wines from a warm climate.

PubMed

Gordillo, Belén; Cejudo-Bastante, María Jesús; Rodríguez-Pulido, Francisco J; Jara-Palacios, M José; Ramírez-Pérez, Pilar; González-Miret, M Lourdes; Heredia, Francisco J

2014-03-26

The influence of the fermentative addition of Pedro Ximenez grape pomace (PXGP, white variety) on the phenolic composition and color of Syrah red wines from a warm climate was studied. Changes on phenolic composition (HPLC), copigmentation/polymerization (spectrophotometry), and color (tristimulus colorimetry) allowed differences among the maceration treatments to be established. PXGP additions at the rates studied increased the extraction of total phenolics, phenolic acids, and monomeric flavanols. However, the effect on the anthocyanins, copigmentation, and polymerization depended on the doses applied, with important consequences on the color. PXGP addition at 10% led to wines with higher polymerization, more stable colors, and bluish hues. in contrast, perceptibly lighter and less intense wines were obtained with PXGP addition at 20%. Thus, the use of white grape byproducts as wine additives at appropriate levels (10% w/w) could improve the phenolic potential of red young wines from a warm climate, contributing to preserve their color characteristic.

Phenolic compounds and biological effects of edible Rumex scutatus and Pseudosempervivum sempervivum: potential sources of natural agents with health benefits.

PubMed

Savran, Ahmet; Zengin, Gokhan; Aktumsek, Abdurrahman; Mocan, Andrei; Glamoćlija, Jasmina; Ćirić, Ana; Soković, Marina

2016-07-13

The present study outlines a chemical characterization and further effects beneficial to health of edible Rumex scutatus and Pseudosempervivum sempervivum, in addition to presenting the antioxidant, enzyme inhibitory effects and antimicrobial properties of different extracts. The phenolic compounds composition of the extracts was assessed by RP-HPLC-DAD, outlining benzoic acid and rutin as major constituents in P. sempervivum and rutin and hesperidin in R. scutatus. Moreover, further biological effects were tested on key enzymes involved in diabetes mellitus, Alzheimer's disease and skin melanogenesis revealing an important tyrosinase inhibitory effect of Pseudosempervivum water extract. Moreover, both species possessed antimicrobial properties towards bacteria and fungi relevant to public health. Accordingly, we find that R. scutatus and P. sempervivum can be considered as novel functional foods because they are rich sources of biologically active compounds that provide health benefits.

Characterization of virgin walnut oils and their residual cakes produced from different varieties.

PubMed

Ojeda-Amador, Rosa M; Salvador, María Desamparados; Gómez-Alonso, Sergio; Fregapane, Giuseppe

2018-06-01

This study addresses the composition and properties of different walnut varieties (Chandler, Hartley and Lara), in particular their virgin oils and residual cakes obtained by screw pressing employing different cultivars. Among nuts, walnut (Juglans regia L.) exhibits interesting nutritional value, mainly due to their high content in linoleic acid, phenolic and tocopherol compounds, which show antioxidant and other healthy properties. Valuable results related to fatty acid profile and minor components were observed. Virgin walnut oil is a rich source in linoleic acid (60-62%) and γ-tocopherol (517-554 mg/kg). Moreover, walnuts show a very high content in total phenolic compounds (10,045-12,474 mg/kg; as gallic acid), which contribute to a great antioxidant activity (105-170 mmol/kg for DPPH, and 260-393 mmol/kg for ORAC), being the hydrolysable tannins (2132-4204 mg/kg) and flavanols (796-2433 mg/kg) their main phenolic groups. Aldehydes account for the highest contribution to aromatic volatiles in virgin walnut oil (about 35% of total). As expected, polar phenolic compounds concentrate in the residual cake, after the separation of the oily phase, reaching a content of up to 19,869 mg/kg, leading to potential added value and applications as source of bioactive compounds to this by-product. Copyright © 2018 Elsevier Ltd. All rights reserved.

Green synthesis of silver nanoparticles using Stevia leaves extracts

NASA Astrophysics Data System (ADS)

Laguta, Iryna; Stavinskaya, Oksana; Kazakova, Olga; Fesenko, Tetiana; Brychka, Sergey

2018-02-01

Three extracts of Stevia rebaudiana (Bertoni) were prepared using different types of raw materials: leaves of plants grown ex situ, leaves of plants grown in vitro, callus culture formed on damaged leaves. Composition of the extracts was studied by means of high-performance liquid chromatography and laser desorption/ionization mass spectrometry; total phenol content was estimated using Folin-Ciocalteau method. Flavonoids and hydroxycinnamic acids were found to be the main groups of phenol antioxidants available in the Stevia leaves, with the amount of these compounds in the extract being dependent on the type of raw material. The reducing properties of phenol compounds identified in the extracts were characterized using quantum chemical method; flavonoids and hydroxycinnamic acids were found to have similar redox parameters. Silver nanoparticles (AgNPs) colloids were synthesized using three Stevia extracts; AgNPs size distribution were characterized by means of scanning electron microscopy. All the extracts revealed significant activity in AgNPs synthesis; the nanoparticles of predominantly spherical shape with the average sizes of 16-25 nm were formed. The reducing properties of the extracts were found to correlate with total phenol content; the activity of extracts from the leaves of plants grown ex situ and from callus culture in Ag+ ions reduction was similar to each other and exceeded the activity of extract from the leaves of plants grown in vitro.

Reversed Phase HPLC-DAD Profiling of Carotenoids, Chlorophylls and Phenolic Compounds in Adiantum capillus-veneris Leaves

NASA Astrophysics Data System (ADS)

Zeb, Alam; Ullah, Fareed

2017-04-01

Adiantum capillus-veneris is important endangered fern species with several medicinal properties. In this study, the leaves samples were extracted and separated using reversed phase HPLC with DAD for carotenoids, chlorophylls and phenolic compounds. Separation of carotenoids and chlorophylls were carried out using a tertiary gradient system of water, MTBE and methanol-water, while a binary gradient system of methanol-water-acetic acid was used for phenolic profiling. Results revealed eight carotenoids, four pheophytins and two chlorophylls. Lutein (806.0 µg/g), chlorophyll b' (410.0 µg/g), chlorophyll a (162.4 µg/g), 9'-Z-neoxanthin (142.8 µg/g) and all-E-violaxanthin (82.2 µg/g)) were present in higher amounts. The relatively high amounts of lutein may be one of the key indicator of beneficial antioxidant properties. The phenolic profile revealed a total of thirteen compounds, namely p-hydroxybenzoic acid, chlorogenic acid, caftaric acid, kaempferol glycosides, p-coumaric acid, rosmarinic acid, 5-caffeoylquinic acid, and quercetin glycosides. Kaempferol-3-sophorotrioside (58.7 mg/g), chlorogenic acid (28.5 mg/g), 5-O-caffeoylquinic acid (18.7 mg/g), coumaric acid (11.2 mg/g) and its derivative (33.1 mg/g) were present in high amounts. These results suggest that the reversed phase HPLC profiling of adiantum leaves provides a better understanding in to the actual composition of bioactive compounds, which may be responsible for possible medicinal properties. Adiantum leaves rich in important bioactive phytochemicals can be used as a potential source of nutraceuticals or as a functional food ingredient.

Reversed Phase HPLC-DAD Profiling of Carotenoids, Chlorophylls and Phenolic Compounds in Adiantum capillus-veneris Leaves

PubMed Central

Zeb, Alam; Ullah, Fareed

2017-01-01

Adiantum capillus-veneris is important endangered fern species with several medicinal properties. In this study, the leaves samples were extracted and separated using reversed phase HPLC with DAD for carotenoids, chlorophylls and phenolic compounds. Separation of carotenoids and chlorophylls were carried out using a tertiary gradient system of water, MTBE and methanol-water, while a binary gradient system of methanol-water-acetic acid was used for phenolic profiling. Results revealed eight carotenoids, four pheophytins, and two chlorophylls. Lutein (806.0 μg/g), chlorophyll b′ (410.0 μg/g), chlorophyll a (162.4 μg/g), 9′-Z-neoxanthin (142.8 μg/g) and all-E-violaxanthin (82.2 μg/g) were present in higher amounts. The relatively high amounts of lutein may be one of the key indicator of beneficial antioxidant properties. The phenolic profile revealed a total of 13 compounds, namely 4-hydroxybenzoic acid, chlorogenic acid, caftaric acid, kaempferol glycosides, p-coumaric acid, rosmarinic acid, 5-caffeoylquinic acid, and quercetin glycosides. Kaempferol-3-sophorotrioside (58.7 mg/g), chlorogenic acid (28.5 mg/g), 5-O-caffeoylquinic acid (18.7 mg/g), coumaric acid (11.2 mg/g), and its derivative (33.1 mg/g) were present in high amounts. These results suggest that the reversed phase HPLC profiling of Adiantum leaves provides a better understanding in to the actual composition of bioactive compounds, which may be responsible for the potential medicinal properties. Adiantum leaves rich in important bioactive phytochemicals can be used as a possible source of nutraceuticals or as a functional food ingredient. PMID:28497036

Reversed Phase HPLC-DAD Profiling of Carotenoids, Chlorophylls and Phenolic Compounds in Adiantum capillus-veneris Leaves.

PubMed

Zeb, Alam; Ullah, Fareed

2017-01-01

Adiantum capillus-veneris is important endangered fern species with several medicinal properties. In this study, the leaves samples were extracted and separated using reversed phase HPLC with DAD for carotenoids, chlorophylls and phenolic compounds. Separation of carotenoids and chlorophylls were carried out using a tertiary gradient system of water, MTBE and methanol-water, while a binary gradient system of methanol-water-acetic acid was used for phenolic profiling. Results revealed eight carotenoids, four pheophytins, and two chlorophylls. Lutein (806.0 μg/g), chlorophyll b ' (410.0 μg/g), chlorophyll a (162.4 μg/g), 9'- Z -neoxanthin (142.8 μg/g) and all- E -violaxanthin (82.2 μg/g) were present in higher amounts. The relatively high amounts of lutein may be one of the key indicator of beneficial antioxidant properties. The phenolic profile revealed a total of 13 compounds, namely 4-hydroxybenzoic acid, chlorogenic acid, caftaric acid, kaempferol glycosides, p-coumaric acid, rosmarinic acid, 5-caffeoylquinic acid, and quercetin glycosides. Kaempferol-3-sophorotrioside (58.7 mg/g), chlorogenic acid (28.5 mg/g), 5- O -caffeoylquinic acid (18.7 mg/g), coumaric acid (11.2 mg/g), and its derivative (33.1 mg/g) were present in high amounts. These results suggest that the reversed phase HPLC profiling of Adiantum leaves provides a better understanding in to the actual composition of bioactive compounds, which may be responsible for the potential medicinal properties. Adiantum leaves rich in important bioactive phytochemicals can be used as a possible source of nutraceuticals or as a functional food ingredient.

Berry ripening, pre-processing and thermal treatments affect the phenolic composition and antioxidant capacity of grape (Vitis vinifera L.) juice.

PubMed

Genova, Giuseppe; Tosetti, Roberta; Tonutti, Pietro

2016-01-30

Grape juice is an important dietary source of health-promoting antioxidant molecules. Different factors may affect juice composition and nutraceutical properties. The effects of some of these factors (harvest time, pre-processing ethylene treatment of grapes and juice thermal pasteurization) were here evaluated, considering in particular the phenolic composition and antioxidant capacity. Grapes (Vitis vinifera L., red-skinned variety Sangiovese) were collected twice in relation to the technological harvest (TH) and 12 days before TH (early harvest, EH) and treated with gaseous ethylene (1000 ppm) or air for 48 h. Fresh and pasteurized (78 °C for 30 min) juices were produced using a water bath. Three-way analysis of variance showed that the harvest date had the strongest impact on total polyphenols, hydroxycinnamates, flavonols, and especially on total flavonoids. Pre-processing ethylene treatment significantly increased the proanthocyanidin, anthocyanin and flavan-3-ol content in the juices. Pasteurization induced a significant increase in anthocyanin concentration. Antioxidant capacity was enhanced by ethylene treatment and pasteurization in juices from both TH and EH grapes. These results suggest that an appropriate management of grape harvesting date, postharvest and processing may lead to an improvement in nutraceutical quality of juices. Further research is needed to study the effect of the investigated factors on juice organoleptic properties. © 2015 Society of Chemical Industry.

Mineral composition, nutritional properties, total phenolics and flavonoids compounds of the atemoya fruit (Annona squamosa L. x Annona cherimola Mill.) and evaluation using multivariate analysis techniques.

PubMed

Santos, Walter N L Dos; Sauthier, Maria Celeste S; Cavalcante, Dannuza D; Benevides, Clícia M J; Dias, Fábio S; Santos, Daniele C M B

2016-09-01

The atemoya is a hybrid fruit obtained by crossing of cherimoya (Annona cherimola Mill.) with sweet sop (Annona squamosa L.). The information about chemical composition of atemoya is scarce. The mineral composition was evaluated employing Inductively Coupled Plasma Optical Emission Spectrometry (ICP OES) and the centesimal composition and the physico-chemical parameters were assessed employing procedures described in the AOAC methods. The total phenolic compounds (TPC) and total flavonoids (TF) were determined using spectroanalytical methods. Considering the Reference Daily Intake (RDI), the concentrations of K, Cu and Vitamin C found in atemoya were the highest, representing about 32, 23 and 37% of the RDI, respectively. The total carbohydrates were 32 g 100g-1 and the soluble solids was equivalent to (32.50 ± 0.03) °Brix. The result for TPC was 540.47 ± 2.32 mgGAE 100 g-1 and the TF was 11.56 ± 1.36 mgQE 100 g-1. The exploratory evaluation of 42 atemoya samples was performed through Principal Component Analysis (PCA), which discriminated green and ripe fruits according to their mineral composition. The elements that contributed most for the variability between green and ripe fruits were: Ba, Ca, Cu, K, Mg and P.

Contribution of several volatile phenols and their glycoconjugates to smoke-related sensory properties of red wine.

PubMed

Parker, Mango; Osidacz, Patricia; Baldock, Gayle A; Hayasaka, Yoji; Black, Cory A; Pardon, Kevin H; Jeffery, David W; Geue, Jason P; Herderich, Markus J; Francis, I Leigh

2012-03-14

Guaiacol and 4-methylguaiacol are well-known as contributors to the flavor of wines made from smoke-affected grapes, but there are other volatile phenols commonly found in smoke from forest fires that are also potentially important. The relationships between the concentration of a range of volatile phenols and their glycoconjugates with the sensory characteristics of wines and model wines were investigated. Modeling of the attribute ratings from a sensory descriptive analysis of smoke-affected wines with their chemical composition indicated the concentrations of guaiacol, o-cresol, m-cresol, and p-cresol were related to smoky attributes. The best-estimate odor thresholds of these compounds were determined in red wine, together with the flavor threshold of guaiacol. Guaiacol β-D-glucoside and m-cresol β-D-glucoside in model wine were found to give rise to a smoky/ashy flavor in-mouth, and the respective free volatiles were released. The study indicated that a combination of volatile phenols and their glycosides produces an undesirable smoke flavor in affected wines. The observation of flavor generation from nonvolatile glycoconjugates in-mouth has potentially important implications.

Influence of genotype, cultivation system and irrigation regime on antioxidant capacity and selected phenolics of blueberries (Vaccinium corymbosum L.).

PubMed

Cardeñosa, Vanessa; Girones-Vilaplana, Amadeo; Muriel, José Luis; Moreno, Diego A; Moreno-Rojas, José M

2016-07-01

Demand for and availability of blueberries has increased substantially over recent years, driven in part by their health-promoting properties. Three blueberry varieties ('Rocío', V2, and V3) were grown under two cultivation systems (open-field and plastic tunnels) and subjected to two irrigations regimes (100% and 80% of crop evapotranspiration) in two consecutive years (2011-2012). They were evaluated for their phytochemical composition and antioxidant capacity. Genotype influenced the antioxidant capacity and the content of the three groups of phenolics in the blueberries. The antioxidant activity and total flavonols content increased when the blueberries were grown under open-field conditions. Deficit irrigation conditions led to additional positive effects on their phenolics (delphinidn-3-acetilhexoside content was increased under plastic tunnel with deficit irrigation). In conclusion, the amount of phenolic compounds and the antioxidant capacity of blueberries were not negatively affected by water restriction; Moreover, several changes were recorded due to growing system and genotype. Copyright © 2016 Elsevier Ltd. All rights reserved.

Comparative study of antioxidant properties and total phenolic content of 30 plant extracts of industrial interest using DPPH, ABTS, FRAP, SOD, and ORAC assays.

PubMed

Dudonné, Stéphanie; Vitrac, Xavier; Coutière, Philippe; Woillez, Marion; Mérillon, Jean-Michel

2009-03-11

Aqueous extracts of 30 plants were investigated for their antioxidant properties using DPPH and ABTS radical scavenging capacity assay, oxygen radical absorbance capacity (ORAC) assay, superoxide dismutase (SOD) assay, and ferric reducing antioxidant potential (FRAP) assay. Total phenolic content was also determined by the Folin-Ciocalteu method. Antioxidant properties and total phenolic content differed significantly among selected plants. It was found that oak (Quercus robur), pine (Pinus maritima), and cinnamon (Cinnamomum zeylanicum) aqueous extracts possessed the highest antioxidant capacities in most of the methods used, and thus could be potential rich sources of natural antioxidants. These extracts presented the highest phenolic content (300-400 mg GAE/g). Mate (Ilex paraguariensis) and clove (Eugenia caryophyllus clovis) aqueous extracts also showed strong antioxidant properties and a high phenolic content (about 200 mg GAE/g). A significant relationship between antioxidant capacity and total phenolic content was found, indicating that phenolic compounds are the major contributors to the antioxidant properties of these plants.

Evaluation of antioxidant properties, elemental and phenolic contents composition of wild nettle (Urtica dioica L.) from Tunceli in Turkey.

PubMed

Yildirim, N C; Turkoglu, S; Ince, O K; Ince, M

2013-11-03

Wild nettle (Urtica dioica L.) types were sampled from different geographical regions in Tunceli (Turkey) to determine their mineral, vitamin, phenolic contents and their antioxidant properties. The total phenol varied from 37.419 ± 0.380 to 19.182 ± 1.00 mg of GAEs g(-1) of dry nettle. The highest radical scavenging effect was observed in Mazgirt parting of the ways 7.5 km with 33.70 ± 0.849 mg mL(-1). The highest reducing power was observed in the nettles from Mazgirt parting of the ways 7.5 km. Among the various macronutrients estimated in the plant samples, potassium was present in the highest quantity followed by calcium and phosphate. Kaempferol and resveratrol were not determined in some nettle samples but rutin levels were determined in all samples. Vitamin A concentrations were ranged between 13.64 ± 1.90 and 5.74 ± 1.00 (mg kg(-1) dry weight). These results show that Urtica dioica L. collected from Tunceli in Turkey could be considered as a natural alternative source for food, pharmacology and medicine sectors.

Food ingredient extracts of Cyclopia subternata (Honeybush): variation in phenolic composition and antioxidant capacity.

PubMed

de Beer, Dalene; Schulze, Alexandra E; Joubert, Elizabeth; de Villiers, André; Malherbe, Christiaan J; Stander, Maria A

2012-12-07

Cyclopia subternata plants are traditionally used for the production of the South African herbal tea, honeybush, and recently as aqueous extracts for the food industry. A C. subternata aqueous extract and mangiferin (a major constituent) are known to have anti-diabetic properties. Variation in phenolic composition and antioxidant capacity is expected due to cultivation largely from seedlings, having implications for extract standardization and quality control. Aqueous extracts from 64 seedlings of the same age, cultivated under the same environmental conditions, were analyzed for individual compound content, total polyphenol (TP) content and total antioxidant capacity (TAC) in a number of assays. An HPLC method was developed and validated to allow quantification of xanthones (mangiferin, isomangiferin), flavanones (hesperidin, eriocitrin), a flavone (scolymoside), a benzophenone (iriflophenone-3-C-β-glucoside) and dihydrochalcones (phloretin-3',5'-di-C-β-glucoside, 3-hydroxyphloretin-3',5'-di-C-hexoside). Additional compounds were tentatively identified using mass spectrometric detection, with the presence of the 3-hydroxyphloretin-glycoside, an iriflophenone-di-O,C-hexoside, an eriodictyol-di-C-hexoside and vicenin-2 being demonstrated for the first time. Variability of the individual phenolic compound contents was generally higher than that of the TP content and TAC values. Among the phenolic compounds, scolymoside, hesperidin and iriflophenone-3-C-β-glucoside contents were the most variable. A combination of the measured parameters could be useful in product standardization by providing a basis for specifying minimum levels.

Comparative Studies on Phenolic Composition, Antioxidant, Wound Healing and Cytotoxic Activities of Selected Achillea L. Species Growing in Turkey.

PubMed

Agar, Osman Tuncay; Dikmen, Miris; Ozturk, Nilgun; Yilmaz, Mustafa Abdullah; Temel, Hamdi; Turkmenoglu, Fatma Pinar

2015-09-30

Turkey is one of the most important centers of diversity for the genus Achillea L. in the world. Keeping in mind the immense medicinal importance of phenols, in this study, three species growing in Turkey, A. coarctata Poir. (AC), A. kotschyi Boiss. subsp. kotschyi (AK) and A. lycaonica Boiss. & Heldr. (AL) were evaluated for their phenolic compositions, total phenolic contents (TPC), antioxidant properties, wound healing potencies on NIH-3T3 fibroblasts and cytotoxic effects on MCF-7 human breast cancer cells. Comprehensive LC-MS/MS analysis revealed that AK was distinctively rich in chlorogenic acid, hyperoside, apigenin, hesperidin, rutin, kaempferol and luteolin (2890.6, 987.3, 797.0, 422.5, 188.1, 159.4 and 121.2 µg analyte/g extract, respectively). The findings exhibited a strong correlation between TPC and both free radical scavenging activity and total antioxidant capacity (TAC). Among studied species, the highest TPC (148.00 mg GAE/g extract) and TAC (2.080 UAE), the strongest radical scavenging (EC50 = 32.63 μg/mL), the most prominent wound healing and most abundant cytotoxic activities were observed with AK. The results suggested that AK is a valuable source of flavonoids and chlorogenic acid with important antioxidant, wound healing and cytotoxic activities. These findings warrant further studies to assess the potential of AK as a bioactive source that could be exploited in pharmaceutical, cosmetics and food industries.

The effect of phenol composition on the sensory profile of smoke affected wines.

PubMed

Kelly, David; Zerihun, Ayalsew

2015-05-26

Vineyards exposed to wildfire generated smoke can produce wines with elevated levels of lignin derived phenols that have acrid, metallic and smoky aromas and flavour attributes. While a large number of phenols are present in smoke affected wines, the effect of smoke vegetation source on the sensory descriptors has not been reported. Here we report on a descriptive sensory analysis of wines made from grapes exposed to different vegetation sources of smoke to examine: (1) the effect vegetation source has on wine sensory attribute ratings and; (2) associations between volatile and glycoconjugated phenol composition and sensory attributes. Sensory attribute ratings were determined by a trained sensory panel and phenol concentrations determined by gas chromatography-mass spectroscopy. Analysis of variance, principal component analysis and partial least squares regressions were used to evaluate the interrelationships between the phenol composition and sensory attributes. The results showed that vegetation source of smoke significantly affected sensory attribute intensity, especially the taste descriptors. Differences in aroma and taste from smoke exposure were not limited to an elevation in a range of detractive descriptors but also a masking of positive fruit descriptors. Sensory differences due to vegetation type were driven by phenol composition and concentration. In particular, the glycoconjugates of 4-hydroxy-3-methoxybenzaldehyde (vanillin), 1-(4-hydroxy-3-methoxyphenyl)ethanone (acetovanillone), 4-hydroxy-3,5-dimethoxybenzaldehyde (syringaldehyde) and 1-(4-hydroxy-3,5-dimethoxyphenyl)ethanone (acetosyringone) concentrations were influential in separating the vegetation sources of smoke. It is concluded that the detractive aroma attributes of smoke affected wine, especially of smoke and ash, were associated with volatile phenols while the detractive flavour descriptors were correlated with glycoconjugated phenols.

Process for preparing phenolic formaldehyde resole resin products derived from fractionated fast-pyrolysis oils

DOEpatents

Chum, Helena L.; Kreibich, Roland E.

1992-01-01

A process for preparing phenol-formaldehyde resole resins and adhesive compositions in which portions of the phenol normally contained in said resins are replaced by a phenol/neutral fractions extract obtained from fractionating fast-pyrolysis oils.

Phenolics content and antioxidant activity of tartary buckwheat from different locations.

PubMed

Guo, Xu-Dan; Ma, Yu-Jie; Parry, John; Gao, Jin-Ming; Yu, Liang-Li; Wang, Min

2011-11-25

Two tartary buckwheat samples (Xingku No.2 and Diqing) grown at three locations were analyzed for free and bound phenolic content and antioxidant properties. Moreover, the relative contributions of variety and growing environment to phenolic content and antioxidant properties were determined, as well as correlations of these properties to growing conditions. The total phenolic contents varied from 5,150 to 9,660 μmol of gallic acid equivalents per 100 gram of dry weight (DW) of tartary buckwheat and the free phenolics accounted for 94% to 99%. Rutin content was in the range from 518.54 to 1,447.87 mg per 100 gram of DW of tartary buckwheat. p-Hydroxybenzoic, ferulic and protocatechuic acids were the prominent phenolic acids and other phenolics, including p-coumaric, gallic, caffeic, vanillic and syringic acids were also detected. Tartary buckwheat exhibited higher DPPH· and ABTS·+ scavenging activities and was more effective at preventing the bleaching of β-carotene in comparison with reference antioxidant and plant phenolics constituents. Additionally, growing conditions and the interaction between variety and environment may have more contribution than variety to individual phenolics and antioxidant properties of tartary buckwheat. Environmental parameters such as higher altitudes may also have an increasing effect on rutin and phenolic acids. This study suggests that tartary buckwheat has potential health benefits because of its high phenolic content and antioxidant properties. These components could also be enhanced by optimizing the growing conditions of a selected variety.

Ultrasonic characterization of silicate glasses, polymer composites and hydrogels

NASA Astrophysics Data System (ADS)

Lee, Wan Jae

In many applications of material designing and engineering, high-frequency linear viscoelastic properties of materials are essential. Traditionally, the high-frequency properties are estimated through the time-temperature superposition (WLF equation) of low-frequency data, which are questionable because the existence of multi-phase in elastomer compounds. Moreover, no reliable data at high frequencies over MHz have been available thus far. Ultrasound testing is cost-effective for measuring high-frequency properties. Although both ultrasonic longitudinal and shear properties are necessary in order to fully characterize high-frequency mechanical properties of materials, longitudinal properties will be extensively explored in this thesis. Ultrasonic pulse echo method measures longitudinal properties. A precision ultrasonic measurement system has been developed in our laboratory, which allows us to monitor the in-situ bulk and/or surface properties of silicate glasses, polymer composites and even hydrogels. The system consists of a pulse-echo unit and an impedance measurement unit. A pulse echo unit is explored mainly. First, a systematic procedure was developed to obtain precise water wavespeed value. A calibration curve of water wavespeed as a function of temperature has been established, and water wavespeed at 23°C serves as a yardstick to tell whether or not a setup is properly aligned. Second, a sound protocol in calculating attenuation coefficient and beam divergence effects was explored using three kinds of silicate glass of different thicknesses. Then the system was applied to four composite slabs, two slabs for each type of fiberglass reinforced plastics, phenolic and polyester manufactured under different processing conditions: one was made by the normal procedures and the other with deliberate flaws such as voids, tapes and/or prepared at improper operation temperature and pressure. The experiment was conducted under the double blind test protocol. After carefully and methodically analyzing the data, we are able to detect defected specimens from all the specimens supplied to us, differentiate polyester-based composite from the phenolic-based composite and even recognized types of defects. Lastly, ultrasonic monitoring of advancement of the swollen-unswollen fronts, and hence monitor phase transition from glassy state to rubbery state, of poly(acrylic-acid) hydrogel of one of the three different crosslinking densities is performed. With ultrasonic measurement, swelling monitoring is possible since the structural and mechanical changes during swelling of a dry hydrogel are related to changes in density and elastic constants. Using our carefully developed methodology from previous chapters, we may obtain and monitor average acoustic properties of each layer of hydrogel as it swells.

High-Performance Cellulose Nanofibril Composite Films

Treesearch

Yan Qing; Ronald Sabo; Yiqiang Wu; Zhiyong Cai

2012-01-01

Cellulose nanofibril/phenol formaldehyde (CNF/PF) composite films with high work of fracture were prepared by filtering a mixture of 2,2,6,6tetramethylpiperidine-1-oxyl (TEMPO) oxidized wood nanofibers and water-soluble phenol formaldehyde with resin contents ranging from 5 to 20 wt%, followed by hot pressing. The composites were characterized by tensile testing,...

Analysis of protein amino acids, non-protein amino acids and metabolites, dietary protein, glucose, fructose, sucrose, phenolic, and flavonoid content and antioxidative properties of potato tubers, peels, and cortexes (pulps)

USDA-ARS?s Scientific Manuscript database

The composition and antioxidative activity of whole potato tubers from five Korean cultivars, three peels from one cultivar, and eight pulps (cortexes) after peeling from six different cultivars were evaluated. The following characteristics were determined: the dimensions and water content of whole...

Total phenolic content, radical scavenging properties, and essential oil composition of Origanum species from different populations.

PubMed

Dambolena, José S; Zunino, María P; Lucini, Enrique I; Olmedo, Rubén; Banchio, Erika; Bima, Paula J; Zygadlo, Julio A

2010-01-27

The aim of this work was to compare the antiradical activity, total phenol content (TPC), and essential oil composition of Origanum vulgare spp. virens, Origanum x applii, Origanum x majoricum, and O. vulgare spp. vulgare cultivated in Argentina in different localities. The experiment was conducted in the research station of La Consulta (INTA-Mendoza), the research station of Santa Lucia (INTA-San Juan), and Agronomy Faculty of National University of La Pampa, from 2007 to 2008. The composition of the essential oils of oregano populations was independent of cultivation conditions. In total, 39 compounds were identified in essential oils of oregano from Argentina by means of GC-MS. Thymol and trans-sabinene hydrate were the most prominent compounds, followed by gamma-terpinene, terpinen-4-ol, and alpha-terpinene. O. vulgare vulgare is the only Origanum studied which is rich in gamma-terpinene. Among tested oregano, O. x majoricum showed the highest essential oil content, 3.9 mg g(-1) dry matter. The plant extract of O. x majoricum had greater total phenol content values, 19.36 mg/g dry weight, than the rest of oregano studied. To find relationships among TPC, free radical scavenging activity (FRSA), and climate variables, canonical correlations were calculated. The results obtained allow us to conclude that 70% of the TPC and FRSA variability can be explained by the climate variables (R(2) = 0.70; p = 8.3 x 10(-6)), the temperature being the most important climatic variable.

Characterization of phenolic compounds in green and red oak-leaf lettuce cultivars by UHPLC-DAD-ESI-QToF/MS using MSE scan mode.

PubMed

Viacava, Gabriela E; Roura, Sara I; Berrueta, Luis A; Iriondo, Carmen; Gallo, Blanca; Alonso-Salces, Rosa M

2017-12-01

Lettuce (Lactuca sativa) is one of the most popular leafy vegetables in the world and constitutes a major dietary source of phenolic compounds with health-promoting properties. In particular, the demand for green and red oak-leaf lettuces has considerably increased in the last years but few data on their polyphenol composition are available. Moreover, the usage of analytical edge technology can provide new structural information and allow the identification of unknown polyphenols. In the present study, the phenolic profiles of green and red oak-leaf lettuce cultivars were exhaustively characterized by ultrahigh-performance liquid chromatography (UHPLC) coupled online to diode array detection (DAD), electrospray ionization (ESI), and quadrupole time-of-flight mass spectrometry (QToF/MS), using the MS E instrument acquisition mode for recording simultaneously exact masses of precursor and fragment ions. One hundred fifteen phenolic compounds were identified in the acidified hydromethanolic extract of freeze-dried lettuce leaves. Forty-eight of these compounds were tentatively identified for the first time in lettuce, and only 20 of them have been previously reported in oak-leaf lettuce cultivars in literature. Both oak-leaf lettuce cultivars presented similar phenolic composition, except for apigenin-glucuronide and dihydroxybenzoic acid, only detected in the green cultivar; and for luteolin-hydroxymalonylhexoside, an apigenin conjugate with molecular formula C 40 H 54 O 19 (monoisotopic MW = 838.3259 u), cyanidin-3-O-glucoside, cyanidin-3-O-(3″-O-malonyl)glucoside, cyanidin-3-O-(6″-O-malonyl)glucoside, and cyanidin-3-O-(6″-O-acetyl)glucoside, only found in the red cultivar. The UHPLC-DAD-ESI-QToF/MS E approach demonstrated to be a useful tool for the characterization of phenolic compounds in complex plant matrices. Copyright © 2017 John Wiley & Sons, Ltd.

Selection of grapevine leaf varieties for culinary process based on phytochemical composition and antioxidant properties.

PubMed

Lima, Adriano; Bento, Albino; Baraldi, Ilton; Malheiro, Ricardo

2016-12-01

Grapevine leaves are an abundant sub-product of vineyards which is devalued in many regions. The objective of this work is to study the antioxidant activity and phytochemical composition of ten grapevine leaf varieties (four red varieties: Tinta Amarela, Tinta Roriz, Touriga Franca, and Touriga Nacional; and six white varieties: Côdega do Larinho, Fernão Pires, Gouveio, Malvasia Fina, Rabigato, and Viosinho) to select varieties to be used as food ingredients. White grapevine leaves revealed higher antioxidant potential. Malvasia Fina reported better antioxidant properties contrasting with Touriga Franca. Phenolic content varied between 112 and 150mgGAEg(-1) of extract (gallic acid equivalents), hydroxycinnamic acid derivatives and flavonols varied between 76 and 108mgCAEg(-1) of extract (caffeic acid equivalents) and 39 and 54mgQEg(-1) of extract (quercetin equivalents). Malvasia Fina is a good candidate for culinary treatment due to its antioxidant properties and composition in bioactive compounds. Copyright © 2016 Elsevier Ltd. All rights reserved.

Modification of the surface adsorption properties of alumina-supported Pd catalysts for the electrocatalytic hydrogenation of phenol.

PubMed

Cirtiu, Ciprian Mihai; Hassani, Hicham Oudghiri; Bouchard, Nicolas-Alexandre; Rowntree, Paul A; Ménard, Hugues

2006-07-04

The electrocatalytic hydrogenation (ECH) of phenol has been studied using palladium supported on gamma-alumina (10% Pd-Al2O3) catalysts. The catalyst powders were suspended in aqueous supporting electrolyte solutions containing methanol and short-chain aliphatic acids (acetic acid, propionic acid, or butyric acid) and were dynamically circulated through a reticulated vitreous carbon cathode. The efficiency of the hydrogenation process was measured as a function of the total electrolytic charge and was compared for different types of supporting electrolyte and for various solvent compositions. Our results show that these experimental parameters strongly affect the overall ECH efficiency of phenol. The ECH efficiency and yields vary inversely with the quantity of methanol present in the electrolytic solutions, whereas the presence of aliphatic carboxylic acids increased the ECH efficiency in proportion to the chain length of the specific acids employed. In all cases, ECH efficiency was directly correlated with the adsorption properties of phenol onto the Pd-alumina catalyst in the studied electrolyte solution, as measured independently using dynamic adsorption isotherms. It is shown that the alumina surface binds the aliphatic acids via the carboxylate terminations and transforms the catalyst into an organically functionalized material. Temperature-programmed mass spectrometry analysis and diffuse-reflectance infrared spectroscopy measurements confirm that the organic acids are stably bound to the alumina surface below 200 degrees C, with coverages that are independent of the acid chain length. These reproducibly functionalized alumina surfaces control the adsorption/desorption equilibrium of the target phenol molecules and allow us to prepare new electrocatalytic materials to enhance the efficiency of the ECH process. The in situ grafting of specific aliphatic acids on general purpose Pd-alumina catalysts offers a new and flexible mechanism to control the ECH process to enhance the selectivity, efficiency, and yields according to the properties of the specific target molecule.

Fatty Acid Profile, Phenolics and Flavonoids Contents in Olea europaea L. Callus Culture cv. cornicabra.

PubMed

Rodríguez-Hernandez, Ludwi; Nájera-Gomez, Humberto; Luján-Hidalgo, Maria Celína; Ruiz-Lau, Nancy; Lecona-Guzmán, Carlos Alberto; Abud-Archila, Miguel; Ruíz-Valdiviezo, Víctor Manuel; Gutiérrez-Miceli, Federico Antonio

2018-05-01

Olive trees are one of the most important oil crops in the world due to the sensorial and nutritional characteristics of olive oil, such as lipid composition and antioxidant content, and the medicinal properties of its leaves. In this paper, callus formation was induced using nodal segments of olive tree (Olea europaea cv. cornicabra) as explants. Fatty acid profile, total phenolic compounds and total flavonoid compounds were determined in callus culture after 15 weeks and compared with leaf and nodal segments tissues. There was no statistical difference in phenolic compounds among leaf, nodal segments and callus culture, whereas flavonoid compounds were higher in leaf. Fatty acid profile was similar in leaf, nodal segments and callus culture and was constituted by hexadecanoic acid, octadecanoic acid, cis-9-octadecenoic acid, cis-9,12-octadecadienoic acid, cis-9,12,15-octadecatrienoic acid. Hexadecanoic acid was the main fatty acid in callus, leaf and nodal segments with 35.0, 39.0 and 40.0% (w/w), of the lipid composition, respectively. With this paper, it is being reported for the first time the capacity of callus culture to accumulate fatty acids. Our results could serve to continue studying the production of fatty acids in callus cultivation as a biotechnological tool to improve different olive cultivars.

Chemical Composition and, Cellular Evaluation of the Antioxidant Activity of Desmodium adscendens Leaves.

PubMed

Muanda, François Nsemi; Bouayed, Jaouad; Djilani, Abdelouaheb; Yao, Chunyan; Soulimani, Rachid; Dicko, Amadou

2011-01-01

Desmodium adscendens plant is widely used as juice or tea in various parts of the world against a wide range of diseases. This study determines the quality and the quantity of polyphenols, flavonoids, anthocyanins, and tannins in D. adscendens leaves by UV-spectrophotometry and RP-HPLC methods. In addition, the antioxidant capacity of these phenolic compounds is evaluated by ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic)), DPPH (2,2-diphenyl-1 picrylhydrazyl), and Cellular tests. D. adscendens leaves are mainly composite of flavonoid compounds with 12.8 mg of catechin equivalent (CE)/g dw. The amounts of total polyphenol compounds are 11.1 mg of gallic acid equivalent (GAE)/g dw. The quantity of total anthocyanin and total tannin compounds is not considerable 0.0182 mg CgE/g dw and 0.39 mg CE/g dw, respectively. A direct correlation between phenolic compounds and antioxidant activity is observed (R(2) = 0.96). The RP-HPLC analyses reveal that the main phenolic compound identified in the methanol-water extract is quercetrin dihydrat (2.11 mg/mL). According to the results, it is observed that D. adscendens leaves possess a considerable scavenging antioxidant and antiradical capacity, therefore these antioxidant properties might increase the therapeutic value of this medicinal plant.

Chemical characterization and bioactive properties of aqueous and organic extracts of Geranium robertianum L.

PubMed

Graça, V C; Barros, Lillian; Calhelha, Ricardo C; Dias, Maria Inês; Carvalho, Ana Maria; Santos-Buelga, Celestino; Santos, P F; Ferreira, Isabel C F R

2016-09-14

Geranium robertianum L. has been used in folk medicine and herbalism practice for the treatment of various conditions, but the study of its bioactivity has been barely addressed. Although its phytochemical composition has received some attention, contributions to the nutritional composition are practically unknown. Herein, G. robertianum gathered in Trás-os-Montes, Northeastern Portugal, was chemically characterized regarding nutritional parameters, and the antioxidant activity and cytotoxicity against several human tumor cell lines and non-tumor porcine liver primary cells of several aqueous and organic extracts were evaluated. G. robertianum showed to be an equilibrated valuable herb, rich in carbohydrates and proteins, and poor in fat, providing sugars, tocopherols, organic and essential fatty acids. Amongst the extracts, the acetone one showed the highest total phenol and total flavonoid contents, as well as the greatest antioxidant and cytotoxic activities. This extract showed to contain hydrolysable tannins (e.g. geraniin and castalagin/vescalagin), as the main phenolic compounds.

Phytochemical composition and antimicrobial activities of the essential oils and organic extracts from pelargonium graveolens growing in Tunisia

PubMed Central

2012-01-01

Background Pelargonium graveolens (P. graveolens) L. is an aromatic and medicinal plant belonging to the geraniacea family. Results The chemical compositions of the essential oil as well as the in vitro antimicrobial activities were investigated. The GC-MS analysis of the essential oil revealed 42 compounds. Linallol L, Citronellol, Geraniol, 6-Octen-1-ol, 3,7-dimethyl, formate and Selinene were identified as the major components. The tested oil and organic extracts exhibited a promising antimicrobial effect against a panel of microorganisms with diameter inhibition zones ranging from 12 to 34 mm and MICs values from 0.039 to10 mg/ml. The investigation of the phenolic content showed that EtOAc, MeOH and water extracts had the highest phenolic contents. Conclusion Overall, results presented here suggest that the essential oil and organic extracts of P. graveolens possesses antimicrobial and properties, and is therefore a potential source of active ingredients for food and pharmaceutical industry. PMID:23216669

Physicochemical properties of quinoa flour as affected by starch interactions.

PubMed

Li, Guantian; Zhu, Fan

2017-04-15

There has been growing interest in whole grain quinoa flour for new product development due to the unique nutritional benefits. The quality of quinoa flour is much determined by the properties of its major component starch as well as non-starch components. In this study, composition and physicochemical properties of whole grain flour from 7 quinoa samples have been analyzed. Flour properties have been correlated to the flour composition and the properties of isolated quinoa starches through chemometrics. Great variations in chemical composition, swelling power, water soluble index, enzyme susceptibility, pasting, gel texture, and thermal properties of the flour have been observed. Correlation analysis showed that thermal properties and enzyme susceptibility of quinoa flour are highly influenced by the starch. Interactions of starch with non-starch components, including lipids, protein, dietary fibre, phenolics, and minerals, greatly impacted the flour properties. For example, peak gelatinization temperature of the flour is positively correlated to that of the starch (r=0.948, p<0.01) and negatively correlated to the lipid content (r=-0.951, p<0.01). Understanding the roles of starch and other components in physicochemical properties of quinoa flour provides a basis for better utilization of this specialty crop. Copyright © 2016 Elsevier Ltd. All rights reserved.

Nutritional Composition and Antioxidant Properties of Cucumis dipsaceus Ehrenb. ex Spach Leaf

PubMed Central

Chandran, Rahul; Nivedhini, V.; Parimelazhagan, Thangaraj

2013-01-01

The leaf of C. dipsaceus was evaluated for its nutritional and antioxidant properties. From the present investigation, significant amount of almost all essential amino acids and important minerals were quantified. Low levels of trypsin inhibitory units, phenolics, and tannins content were found as antinutritional content. Further, hot water extract of C. dipsaceus showed good activity especially in ABTS+, metal chelating, nitric oxide, and DPPH assays. Hence, the results conclude that C. dipsaceus could be a valuable nutraceutical supplement to the human diet. PMID:24288509

White wine taste and mouthfeel as affected by juice extraction and processing.

PubMed

Gawel, Richard; Day, Martin; Van Sluyter, Steven C; Holt, Helen; Waters, Elizabeth J; Smith, Paul A

2014-10-15

The juice used to make white wine can be extracted using various physical processes that affect the amount and timing of contact of juice with skins. The influence of juice extraction processes on the mouthfeel and taste of white wine and their relationship to wine composition were determined. The amount and type of interaction of juice with skins affected both wine total phenolic concentration and phenolic composition. Wine pH strongly influenced perceived viscosity, astringency/drying, and acidity. Despite a 5-fold variation in total phenolics among wines, differences in bitter taste were small. Perceived viscosity was associated with higher phenolics but was not associated with either glycerol or polysaccharide concentration. Bitterness may be reduced by using juice extraction and handling processes that minimize phenolic concentration, but lowering phenolic concentration may also result in wines of lower perceived viscosity.

Chemical compounds and mechanisms involved in the formation and stabilization of foam in sparkling wines.

PubMed

Kemp, Belinda; Condé, Bruna; Jégou, Sandrine; Howell, Kate; Vasserot, Yann; Marchal, Richard

2018-02-08

The visual properties of sparkling wine including foam and bubbles are an indicator of sparkling wine quality. Foam properties, particularly foam height (FH) and foam stability (TS), are significantly influenced by the chemical composition of the wine. This review investigates our current knowledge of specific chemical compounds and, the mechanisms by which they influence the foam properties of sparkling wines. Grape and yeast proteins, amino acids, polysaccharides, phenolic compounds, organic acids, fatty acids, ethanol and sugar are examined with respect to their contribution to foam characteristics in sparkling wines made with the Traditional, Transfer, and Charmat and carbonation methods. Contradictory results have been identified that appear to be due to the analytical methods used to measure and quantify compounds and foam. Biopolymer complexes are discussed and absent knowledge with regards to thaumatin-like proteins (TLPs), polysaccharides, amino acids, oak-derived phenolic compounds and organic acids are identified. Future research is also likely to concentrate on visual analysis of sparkling wines by in-depth imaging analysis and specific sensory analysis techniques.

Development of Mushroom-Based Cosmeceutical Formulations with Anti-Inflammatory, Anti-Tyrosinase, Antioxidant, and Antibacterial Properties.

PubMed

Taofiq, Oludemi; Heleno, Sandrina A; Calhelha, Ricardo C; Alves, Maria José; Barros, Lillian; Barreiro, Maria Filomena; González-Paramás, Ana M; Ferreira, Isabel C F R

2016-10-14

The cosmetic industry is in a constant search for natural compounds or extracts with relevant bioactive properties, which became valuable ingredients to design cosmeceutical formulations. Mushrooms have been markedly studied in terms of nutritional value and medicinal properties. However, there is still slow progress in the biotechnological application of mushroom extracts in cosmetic formulations, either as antioxidants, anti-aging, antimicrobial, and anti-inflammatory agents or as hyperpigmentation correctors. In the present work, the cosmeceutical potential of ethanolic extracts prepared from Agaricus bisporus , Pleurotus ostreatus , and Lentinula edodes was analyzed in terms of anti-inflammatory, anti-tyrosinase, antioxidant, and antibacterial activities. The extracts were characterized in terms of phenolic acids and ergosterol composition, and further incorporated in a base cosmetic cream to achieve the same bioactive purposes. From the results obtained, the final cosmeceutical formulations presented 85%-100% of the phenolic acids and ergosterol levels found in the mushroom extracts, suggesting that there was no significant loss of bioactive compounds. The final cosmeceutical formulation also displayed all the ascribed bioactivities and as such, mushrooms can further be exploited as natural cosmeceutical ingredients.

Magnetocaloric effect and corrosion resistance of La(Fe, Si)13 composite plates bonded by different fraction of phenolic resin

NASA Astrophysics Data System (ADS)

Zhang, K. S.; Xue, J. N.; Wang, Y. X.; Sun, H.; Long, Y.

2018-04-01

La(Fe, Si)13-based composite plates were successfully fabricated using different amount of phenolic resin. The introduction of phenolic resin as binder increased the corrosion resistance and maintained giant magnetocaloric effect for La(Fe, Si)13-based composite plates. It was found that corroded spots were firstly observed on the boundaries between resin and La(Fe, Si)13 particles, rather than in La(Fe, Si)13-based particles, after being immersed in static distilled water. The corrosion rate decreased significantly with the increase of resin content. And the increase of the content of phenolic resin leads to the reduction of corrosion current density. Meanwhile, the volumetric magnetic entropy change ΔSM decreases slightly as the content of phenolic resin increases. The ΔSM of the plates with 3 wt.%, 5 wt.% and 8 wt.% resin are 63.1, 61.2 and 59.8 mJ/cm3 K under a low magnetic field change of 1 T, respectively.

Structure and photocatalytic activity studies of TiO{sub 2}-supported over Ce-modified Al-MCM-41

DOE Office of Scientific and Technical Information (OSTI.GOV)

Krishna Reddy, Jakkidi; Durgakumari, Valluri, E-mail: durgakumari@iict.res.in; Subrahmanyam, Machiraju

2009-07-01

Ce-Al-MCM-41, TiO{sub 2}/Al-MCM-41 and TiO{sub 2}/Ce-Al-MCM-41 materials with varying contents of Ce (by impregnation) and TiO{sub 2} loaded (by solid-state dispersion) on Al-MCM-41 support are prepared. The Ce modified and TiO{sub 2} loaded composite systems are characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), UV-vis diffuse reflectance spectra (DRS) and X-ray photoelectron spectroscopy (XPS) techniques. The DRS and XPS of low Ce content (0.2-0.5 wt.%) modified Al-MCM-41 samples are showing more characteristic of Ce{sup 3+} species wherein cerium in interaction with Al-MCM-41 and that of high Ce (0.8, 3.0 wt.%) content modified samples are showing the characteristic of bothmore » Ce{sup 4+}and Ce{sup 3+}species. A series of Ce-modified Al-MCM-41 and TiO{sub 2} loaded composite catalysts are evaluated for photocatalytic degradation of phenol under UV irradiation. Low Ce content in Ce{sup 3+} state on Al-MCM-41 is showing good photoactivity in comparison with high Ce content samples and pure ceria. The composite TiO{sub 2}/Ce-Al-MCM-41 is showing enhanced degradation activity due decreased rate of electron-hole recombination on TiO{sub 2} surface by the redox properties of cerium. The photocatalyst TiO{sub 2}/Ce-Al-MCM-41 with an optimum of 10 wt.% TiO{sub 2} and 0.3 wt.% Ce is showing maximum phenol degradation activity. The possible mechanism of phenol degradation on the composite photocatalyst is proposed.« less

Wood Composite Adhesives

NASA Astrophysics Data System (ADS)

Gomez-Bueso, Jose; Haupt, Robert

The global environment, in which phenolic resins are being used for wood composite manufacture, has changed significantly during the last decade. This chapter reviews trends that are driving the use and consumption of phenolic resins around the world. The review begins with recent data on volume usage and regional trends, followed by an analysis of factors affecting global markets. In a section on environmental factors, the impact of recent formaldehyde emission regulations is discussed. The section on economics introduces wood composite production as it relates to the available adhesive systems, with special emphasis on the technical requirement to improve phenolic reactivity. Advances in composite process technology are introduced, especially in regard to the increased demands the improvements place upon adhesive system performance. The specific requirements for the various wood composite families are considered in the context of adhesive performance needs. The results of research into current chemistries are discussed, with a review of recent findings regarding the mechanisms of phenolic condensation and acceleration. Also, the work regarding alternate natural materials, such as carbohydrates, lignins, tannins, and proteinaceous materials, is presented. Finally, new developments in alternative adhesive technologies are reported.

Gelled compositions and well treating

DOE Office of Scientific and Technical Information (OSTI.GOV)

Swanson, B.L.

1984-04-03

Gelled compositions suitable as fracture fluids and water diversion agents comprising water, a polymeric viscosifier, an aldehyde component, and at least one phenolic component such as resorcinol, catechol, and the like, as well as selected oxidized phenolic materials such as 1,4-benzoquinone of natural or synthetic origin and natural and modified tannins. The gelled compositions can additionally contain gel stabilizers and chemical buffering agents.

Gelled compositions and well treating

DOE Office of Scientific and Technical Information (OSTI.GOV)

Swanson, B.L.

1981-01-20

Gelled compositions suitable as fracture fluids and water diversion agents comprising water, a polymeric viscosifier, an aldehyde component, and at least one phenolic component such as resorcinol, catechol, and the like, as well as selected oxidized phenolic materials such as 1,4-benzoquinone of natural or synthetic origin and natural and modified tannins. The gelled compositions can additionally contain gel stabilizers and chemical buffering agents.

Almond (Prunus dulcis (Mill.) D.A. Webb) skins as a potential source of bioactive polyphenols.

PubMed

Monagas, Maria; Garrido, Ignacio; Lebrón-Aguilar, Rosa; Bartolome, Begoña; Gómez-Cordovés, Carmen

2007-10-17

An exhaustive study of the phenolic composition of almond ( Prunus dulcis (Mill.) D.A. Webb) skins was carried out in order to evaluate their potential application as a functional food ingredient. Using the HPLC-DAD/ESI-MS technique, a total of 33 compounds corresponding to flavanols, flavonols, dihydroflavonols and flavanones, and other nonflavonoid compounds were identified. Peaks corresponding to another 23 structure-related compounds were also detected. MALDI-TOF MS was applied to characterize almond skin proanthocyanidins, revealing the existence of a series of A- and B-type procyanidins and propelargonidins up to heptamers, and A- and B-type prodelphinidins up to hexamers. Flavanols and flavonol glycosides were the most abundant phenolic compounds in almond skins, representing up to 38-57% and 14-35% of the total quantified phenolics, respectively. Due to their antioxidant properties, measured as oxygen-radical absorbance capacity (ORAC) at 0.398-0.500 mmol Trolox/g, almond skins can be considered as a value-added byproduct for elaborating dietary antioxidant ingredients.

Electronic eye for the prediction of parameters related to grape ripening.

PubMed

Orlandi, G; Calvini, R; Pigani, L; Foca, G; Vasile Simone, G; Antonelli, A; Ulrici, A

2018-08-15

An electronic eye (EE) for fast and easy evaluation of grape phenolic ripening has been developed. For this purpose, berries of different grape varieties were collected at different harvest times from veraison to maturity, then an amount of the derived must was deposited on a white sheet of absorbent paper to obtain a sort of paper chromatography. Thus, RGB images of the must spots were collected using a flatbed scanner and converted into one-dimensional signals, named colourgrams, which codify the colour properties of the images. The dataset of colourgrams was used to build calibration models to relate the colour of the images with the phenolic composition of the samples - determined by reference analytical methods - and therefore to follow the ripening trend. Satisfactory calibration models were obtained for the prediction of the most important parameters related to phenolic ripening of grapes, such as colour index, tonality, total anthocyanins content, malvidin-3-O-glucoside and petunidin-3-O-glucoside. Copyright © 2018 Elsevier B.V. All rights reserved.

Polishing and parboiling effect on the nutritional and technological properties of pigmented rice.

PubMed

Paiva, Flávia Fernandes; Vanier, Nathan Levien; Berrios, Jose De J; Pinto, Vânia Zanella; Wood, Delilah; Williams, Tina; Pan, James; Elias, Moacir Cardoso

2016-01-15

This study aims to evaluate the effects of polishing and parboiling on proximate composition, structure, phenolic compounds, antioxidant activity, cooking time and hardness of IAC-600 black rice cultivar and MPB-10 red rice lineage. Proximate analysis and light micrographs revealed higher migration of red rice proteins than black rice proteins to the endosperm as a result of parboiling. Parboiling reduced the ash content of red rice while no difference was determined in black rice. Gelatinized starch granules from both genotypes showed similar appearance. There was a decrease in relative crystallinity on both black and red rice subjected to parboiling, which was an indicative of crystallites disruption. Polishing removed more than 90% of free phenolics for both genotypes, while parboiling allowed the partial preservation of free phenolics content in polished rice. Parboiling induced an increase in the cooking time of red rice, but a decrease in the cooking time of black rice. Copyright © 2015 Elsevier Ltd. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yu, Ning; Rahman, Muhammad Mahfuzur; Chen, Jixiang

Steam reforming of simulated bio-oil (ethanol, acetone, phenol, and acetic acid) and phenol has been studied on K-Ni-Cu-Mg-Ce-O/Al 2O 3 composite catalysts. Complementary characterization techniques, such as nitrogen sorption, XRD, H 2-TPR, H 2-TPD, CO-TPD, CO-DRIFTS, and in situ XPS, were used to correlate surface structure and functionality to catalytic performance of potassium (K) doped catalysts. K doping of the Ni-Cu-Mg-Ce-O/Al 2O 3 catalyst created a Ni°/Ni 2+ mixed active phase, which not only enhanced steam reforming activity, but also suppressed the methanation reaction. In addition, K doping changed the surface acid-basic properties of the catalyst, which instead favor themore » gasifcation and water-gas shift reactions. In conclusion, with the combination of these effects, K doping of Ni-Cu-Mg-Ce-O/Al 2O 3 catalysts led to higher C1 yield and much lower methane formation, favoring hydrogen production in steam reforming of both phenol and simulated bio-oil.« less

Modeling of outgassing and matrix decomposition in carbon-phenolic composites

NASA Technical Reports Server (NTRS)

Mcmanus, Hugh L.

1993-01-01

A new release rate equation to model the phase change of water to steam in composite materials was derived from the theory of molecular diffusion and equilibrium moisture concentration. The new model is dependent on internal pressure, the microstructure of the voids and channels in the composite materials, and the diffusion properties of the matrix material. Hence, it is more fundamental and accurate than the empirical Arrhenius rate equation currently in use. The model was mathematically formalized and integrated into the thermostructural analysis code CHAR. Parametric studies on variation of several parameters have been done. Comparisons to Arrhenius and straight-line models show that the new model produces physically realistic results under all conditions.

Nutritional Composition and Antioxidant Capacity in Edible Flowers: Characterisation of Phenolic Compounds by HPLC-DAD-ESI/MSn

PubMed Central

Navarro-González, Inmaculada; González-Barrio, Rocío; García-Valverde, Verónica; Bautista-Ortín, Ana Belén; Periago, María Jesús

2014-01-01

Edible flowers are commonly used in human nutrition and their consumption has increased in recent years. The aim of this study was to ascertain the nutritional composition and the content and profile of phenolic compounds of three edible flowers, monks cress (Tropaeolum majus), marigold (Tagetes erecta) and paracress (Spilanthes oleracea), and to determine the relationship between the presence of phenolic compounds and the antioxidant capacity. Proximate composition, total dietary fibre (TDF) and minerals were analysed according to official methods: total phenolic compounds (TPC) were determined with Folin-Ciocalteu’s reagent, whereas antioxidant capacity was evaluated using Trolox Equivalent Antioxidant Capacity (TEAC) and Oxygen Radical Absorbance Capacity (ORAC) assays. In addition, phenolic compounds were characterised by HPLC-DAD-MSn. In relation to the nutritional value, the edible flowers had a composition similar to that of other plant foods, with a high water and TDF content, low protein content and very low proportion of total fat—showing significant differences among samples. The levels of TPC compounds and the antioxidant capacity were significantly higher in T. erecta, followed by S. oleracea and T. majus. Thirty-nine different phenolic compounds were tentatively identified, with flavonols being the major compounds detected in all samples, followed by anthocyanins and hydroxycynnamic acid derivatives. In T. erecta small proportions of gallotannin and ellagic acid were also identified. PMID:25561232

Assessment of the differences in the phenolic composition and color characteristics of new strawberry (Fragaria x ananassa Duch.) cultivars by HPLC-MS and Imaging Tristimulus Colorimetry.

PubMed

Fernández-Lara, Rebeca; Gordillo, Belén; Rodríguez-Pulido, Francisco J; Lourdes González-Miret, M; Del Villar-Martínez, Alma A; Dávila-Ortiz, Gloria; Heredia, Francisco J

2015-10-01

The phenolic composition (by HPLC-DAD-MS) and color characteristics (by Imaging Tristimulus Colorimetry) of four strawberry cultivars that have shown good climate adaptation to subtropical area (Nikte, Zamorana, Jacona and Pakal) have been assessed. 24 monomeric phenolics were identified, including 15 anthocyanins, 5 phenolic acids, 1 flavanol and 4 flavonols. Nikte and Zamorana showed the highest phenolic potential mainly due to their higher content of anthocyanins, while Pakal was richer in phenolic acids. Regarding color, Nikte and Zamorana were the more similar cultivars having the lowest values of lightness and hue. On the contrary, the color of Pakal was quite different from all the rest, due to the specific distribution between pelargonidin and cyanidin. The inclusion of both phenolic and colorimetric information in the Linear Discriminant Analysis allowed reaching very good discriminations among cultivars. Copyright © 2015 Elsevier Ltd. All rights reserved.

Bioaccessibility and potential bioavailability of phenolic compounds from achenes as a new target for strawberry breeding programs.

PubMed

Ariza, María Teresa; Reboredo-Rodríguez, Patricia; Cervantes, Lucía; Soria, Carmen; Martínez-Ferri, Elsa; González-Barreiro, Carmen; Cancho-Grande, Beatriz; Battino, Maurizio; Simal-Gándara, Jesús

2018-05-15

Strawberry is a major natural source of bioactive compounds. Botanically, strawberry is an aggregate fruit consisting of a fleshy floral receptacle that bears a cluster of real dry fruits (achenes). Existing knowledge on the phenolic composition of achenes and its contribution to that of the whole fruit is limited. Also, the gastric and intestinal bioavailability of phenols is poorly known. In this work, a combination of spectrophotometric and HPLC-DAD methods was used to analyse the phenolic composition of whole fruits and achenes before and after in vitro digestion. Five different phenol families were identified. Also, achenes were found to contribute a sizeable fraction of phenolic acids and hydrolysable tannins in the whole fruit. Because the mere presence of phenolic compounds in a food matrix does not ensure their ready absorption and bioavailability, polyphenol potential bioavailability could be an effective selection criterion for strawberry breeding programs aimed at improving dietary healthiness. Copyright © 2017 Elsevier Ltd. All rights reserved.

Composites

NASA Astrophysics Data System (ADS)

Taylor, John G.

The Composites market is arguably the most challenging and profitable market for phenolic resins aside from electronics. The variety of products and processes encountered creates the challenges, and the demand for high performance in critical operations brings value. Phenolic composite materials are rendered into a wide range of components to supply a diverse and fragmented commercial base that includes customers in aerospace (Space Shuttle), aircraft (interiors and brakes), mass transit (interiors), defense (blast protection), marine, mine ducting, off-shore (ducts and grating) and infrastructure (architectural) to name a few. For example, phenolic resin is a critical adhesive in the manufacture of honeycomb sandwich panels. Various solvent and water based resins are described along with resin characteristics and the role of metal ions for enhanced thermal stability of the resin used to coat the honeycomb. Featured new developments include pultrusion of phenolic grating, success in RTM/VARTM fabricated parts, new ballistic developments for military vehicles and high char yield carbon-carbon composites along with many others. Additionally, global regional market resin volumes and sales are presented and compared with other thermosetting resin systems.

Chemical composition and physicochemical properties of Phaeodactylum tricornutum microalgal residual biomass.

PubMed

German-Báez, L J; Valdez-Flores, M A; Félix-Medina, J V; Norzagaray-Valenzuela, C D; Santos-Ballardo, D U; Reyes-Moreno, C; Shelton, L M; Valdez-Ortiz, A

2017-12-01

The production of photosynthetic biofuels using microalgae is a promising strategy to combat the use of non-renewable energy sources. The microalgae residual biomass is a waste by-product of biofuel production; however, it could prove to have utility in the development of sustainable nutraceuticals and functional foods. In this study, a comprehensive characterisation of the under-utilised Phaeodactylum tricornutum microalgae residual biomass is presented. Proximal composition, antioxidant capacity (using three different antioxidant assays; oxygen radical absorbance capacity; radical cation activity, ABTS; and radical scavenging activity, DPPH), and total phenolic content of free and bound polyphenols were determined. Additionally, the physicochemical properties of water activity, pH, water absorption index, water solubility index, and dispersibility were evaluated. Results revealed that P. tricornutum microalgae residual biomass exhibits a relatively high protein and carbohydrate content, with values of 36.67% and 46.78%, respectively; and most carbohydrates were found as total dietary fibre (45.57%), of which insoluble dietary fibre was the most predominant (43.54%). Antioxidant capacity values for total phytochemicals of 106.22, 67.93, 9.54 µM TE g -1 dw were determined by oxygen radical absorbance capacity, ABTS, and DPPH assays, respectively. Total phenolic content was found to be 2.90 mg GAE g -1 dw. Interestingly, antioxidant capacity and total phenolic content were higher in bound than in free phytochemical extracts. The physicochemical analysis showed P. tricornutum microalgae residual biomass to have suitable properties for the generation of a beverage with Aw, pH, water absorption index, water solubility index, and dispersibility values of 0.45, 7.12, 3.40 g gel g -1  dw, 2.5 g solids 100 g -1  dw, and 90%, respectively. Hence, P. tricornutum microalgae residual biomass could be considered a potential source of bioactive compounds suitable for the production of functional food exhibiting antioxidant capacity and high dietary fibre content.

Effect of olive cultivar on bioaccessibility and antioxidant activity of phenolic fraction of virgin olive oil.

PubMed

Quintero-Flórez, Angélica; Pereira-Caro, Gema; Sánchez-Quezada, Cristina; Moreno-Rojas, José Manuel; Gaforio, José J; Jimenez, Antonio; Beltrán, Gabriel

2017-06-05

This study aims to characterize the phenolic profile and antioxidant capacity of seven monovarietal virgin olive oils (VOOs) and evaluate their in vitro gastrointestinal stability. 'Picual', 'Blanqueta', 'Sevillana', 'Habichuelero', and 'Chetoui' olive cultivars were selected for VOO extraction. The oils were subjected to in vitro digestion. The recovery index (RI) of phenolic compounds after each digestion step and the bioaccessibility index (BI) were evaluated. In addition, the antioxidant activity of the bioaccessible fraction (BF) of VOOs was determined by DPPH, ABTS, and ORAC assays, as well as by studying the intracellular reactive oxygen species in Caco-2 cells. Differences were found in the composition of phenolic compounds in VOOs depending on cultivars. During the digestive process, important losses of phenolic compounds were observed between the buccal and duodenal steps, unlike HTy and Ty, which presented increased recovery due to the hydrolysis of secoiridoid derivatives. Differences in the bioaccessibility of phenolic compounds were found between varieties of VOOs. 'Sevillana' VOO had the highest total bioaccessibility (36%), followed by the 'Picual' (19%), 'Chetoui' (17%), 'Habichuelero' (10%), and 'Blanqueta' (8%) varieties. The BF of all the varieties of VOO showed similar radical ABTS scavenging capacity, 'Chetoui', and 'Blanqueta'-BF having the highest radical DPPH scavenging capacity, and 'Habichuelero' and 'Picual'-BF showing protective effects against the peroxyl radical measured by ORAC FL assay. All VOO-BFs presented decreases in ROS levels in Caco-2 cells. Our results suggest differences in the bioaccessibility of phenolics from diverse VOO varieties, which could lead to different biological properties. Therefore, this study represents a first step toward the development of novel dietary strategies focusing on the phenolic supplementation of different VOOs to preserve human health.

Extraction, identification, fractionation and isolation of phenolic compounds in plants with hepatoprotective effects.

PubMed

Pereira, Carla; Barros, Lillian; Ferreira, Isabel C F R

2016-03-15

The liver is one of the most important organs of human body, being involved in several vital functions and regulation of physiological processes. Given its pivotal role in the excretion of waste metabolites and drugs detoxification, the liver is often subjected to oxidative stress that leads to lipid peroxidation and severe cellular damage. The conventional treatments of liver diseases such as cirrhosis, fatty liver and chronic hepatitis are frequently inadequate due to side effects caused by hepatotoxic chemical drugs. To overcome this problematic paradox, medicinal plants, owing to their natural richness in phenolic compounds, have been intensively exploited concerning their extracts and fraction composition in order to find bioactive compounds that could be isolated and applied in the treatment of liver ailments. The present review aimed to collect the main results of recent studies carried out in this field and systematize the information for a better understanding of the hepatoprotective capacity of medicinal plants in in vitro and in vivo systems. Generally, the assessed plant extracts revealed good hepatoprotective properties, justifying the fractionation and further isolation of phenolic compounds from different parts of the plant. Twenty-five phenolic compounds, including flavonoids, lignan compounds, phenolic acids and other phenolic compounds, have been isolated and identified, and proved to be effective in the prevention and/or treatment of chemically induced liver damage. In this perspective, the use of medicinal plant extracts, fractions and phenolic compounds seems to be a promising strategy to avoid side effects caused by hepatotoxic chemicals. © 2015 Society of Chemical Industry.

Reactivity improvement of cellulolytic enzyme lignin via mild hydrothermal modification.

PubMed

Ma, Zhuoming; Tang, Jiafa; Li, Shujun; Suo, Enxiang

2017-12-01

Isolated by the cellulolytic enzyme lignin (CEL) process, water-alcohol (1:1, v/v) was introduced as co-solvent in the process of the hydrothermal treatment. The modification parameters such as reaction temperature and time, solid-to-liquid ratio, and catalysts (NaOH and NaOAlO 2 ) have been investigated in terms of the specific lignin properties, such as the phenolic hydroxyl content (OH phen ), DPPH free radical scavenging rate, and formaldehyde value. The CELs were also characterized by GPC, FT-IR and 1 H NMR spectroscopy, and Py-GC/MS. The key data are under optimal lignin modification conditions (solid-to-liquid ratio of 1:10 (w/v) and a temperature of 250°C for 60min) are: OH phen content: 2.50mmol/g; half maximal inhibitory concentration (IC 50 ) towards DPPH free radicals: 88.2mg/L; formaldehyde value: 446.9g/kg). Both base catalysts decrease the residue rate, but phenol reactivities of the products were also detracted. Py-GC/MS results revealed that modified lignin had a higher phenolic composition than the CEL did, especially the modified lignin without catalyst (ML), which represented 74.51% phenolic content. Copyright © 2017. Published by Elsevier Inc.

Fate of phytochemicals during malting and fermentation of type III tannin sorghum and impact on product biofunctionality.

PubMed

Kayodé, A P Polycarpe; Mertz, Christian; Guyot, Jean-Pierre; Brat, Pierre; Mouquet-Rivier, Claire

2013-02-27

The aim of the present study was to assess the effects of sorghum bioprocessing into Gowé on iron bioavailability and antioxidant properties of the final products. Gowé is an African sour beverage, whose process combines malting and fermenting of sorghum grains. The effects of the durations of germination and fermentation on the phytochemicals were evaluated using a central composite design. The antioxidant capacity and iron bioavailability of the derived flour were also evaluated. During the germination process, the tannin content of the grain decreased from 429.5 to 174.1 mg/100 g DM, while the total phenolic content increased from 300.3 to 371.5 mg GAE/100 g DM. The phenolic acid contents of the flour were significantly modified as a result of the durations of germination and fermentation. Both germination and fermentation enhanced the antioxidant capacity of sorghum flour, and antioxidant characteristics were significantly correlated with the levels of total phenolics, tannins, and phenolic acids. Phytate content of sorghum grain decreased drastically from 1003 to 369.1 mg/100 g DM when the duration of germination or fermentation increased. This was associated with an increase in the bioavailability of iron.

The phytochemical composition and antioxidant actions of tree nuts

PubMed Central

Bolling, Bradley W; McKay, Diane L; Blumberg, Jeffrey B

2016-01-01

In addition to being a rich source of several essential vitamins and minerals, mono- and polyunsaturated fatty acids, and fiber, most tree nuts provide an array of phytochemicals that may contribute to the health benefits attributed to this whole food. Although many of these constituents remain to be fully identified and characterized, broad classes include the carotenoids, hydrolyzable tannins, lignans, naphthoquinones, phenolic acids, phytosterols, polyphenols, and tocopherols. These phytochemicals have been shown to possess a range of bioactivity, including antioxidant, antiproliferative, anti-inflammatory, antiviral, and hypocholesterolemic properties. This review summarizes the current knowledge of the carotenoid, phenolic, and tocopherol content of tree nuts and associated studies of their antioxidant actions in vitro and in human studies. Tree nuts are a rich source of tocopherols and total phenols and contain a wide variety of flavonoids and proanthocyanidins. In contrast, most tree nuts are not good dietary sources of carotenoids and stilbenes. Phenolic acids are present in tree nuts but a systematic survey of the content and profile of these compounds is lacking. A limited number of human studies indicate these nut phytochemicals are bioaccessible and bioavailable and have antioxidant actions in vivo. PMID:20199996

Mechanical, Optical, and Barrier Properties of Soy Protein Film As Affected by Phenolic Acid Addition.

PubMed

Insaward, Anchana; Duangmal, Kiattisak; Mahawanich, Thanachan

2015-11-04

This study aimed to explore the effect of phenolic acid addition on properties of soy protein film. Ferulic (FE), caffeic (CA), and gallic (GA) acids as well as their oxidized products were used in this study. Phenolic acid addition was found to have a significant effect (p ≤ 0.05) on the mechanical properties of the film. GA-containing films exhibited the highest tensile strength and elongation at break, followed by those with added CA and FE, respectively. Oxidized phenolic acids were shown to produce a film with higher tensile strength and elongation at break than their unoxidized counterparts. Phenolic acid addition also affected film color and transparency. As compared to the control, phenolic-containing film samples demonstrated reduced water vapor permeability and water solubility and increased contact angle, especially at high concentrations of oxidized phenolic acid addition.

Complex Enzyme-Assisted Extraction Releases Antioxidative Phenolic Compositions from Guava Leaves.

PubMed

Wang, Lu; Wu, Yanan; Liu, Yan; Wu, Zhenqiang

2017-09-30

Phenolics in food and fruit tree leaves exist in free, soluble-conjugate, and insoluble-bound forms. In this study, in order to enhance the bioavailability of insoluble-bound phenolics from guava leaves (GL), the ability of enzyme-assisted extraction in improving the release of insoluble-bound phenolics was investigated. Compared to untreated GL, single xylanase-assisted extraction did not change the composition and yield of soluble phenolics, whereas single cellulase or β -glucosidase-assisted extraction significantly enhanced the soluble phenolics content of PGL. However, complex enzyme-assisted extraction (CEAE) greatly improved the soluble phenolics content, flavonoids content, ABTS, DPPH, and FRAP by 103.2%, 81.6%, 104.4%, 126.5%, and 90.3%, respectively. Interestingly, after CEAE, a major proportion of phenolics existed in the soluble form, and rarely in the insoluble-bound form. Especially, the contents of quercetin and kaempferol with higher bio-activity were enhanced by 3.5- and 2.2-fold, respectively. More importantly, total soluble phenolics extracts of GL following CEAE exhibited the highest antioxidant activity and protective effect against supercoiled DNA damage. This enzyme-assisted extraction technology can be useful for extracting biochemical components from plant matrix, and has good potential for use in the food and pharmaceutical industries.

Relationship between red wine grade and phenolics. 2. Tannin composition and size.

PubMed

Kassara, Stella; Kennedy, James A

2011-08-10

Commercial red wines ( Vitis vinifera L. cv. Shiraz) produced during the 2009 vintage underwent winemaker assessment for allocation grade soon after production. The wines were then subjected to phenolic analysis to measure wine color (total anthocyanin, SO(2) nonbleachable pigment, and wine color density) and tannins (concentration, composition, and average degree of polymerization). A positive relationship was found between wine phenolic concentration and projected bottle price. Tannin compositional analysis suggested that there was specifically a relationship between wine grade and skin-derived tannins. These results suggest that maximization of skin tannin concentration and/or proportion is related to an increase in projected wine bottle price.

Tailoring Functional Chitosan-based Composites for Food Applications.

PubMed

Nunes, Cláudia; Coimbra, Manuel A; Ferreira, Paula

2018-03-08

Chitosan-based functional materials are emerging for food applications. The covalent bonding of molecular entities demonstrates to enhance resistance to the typical acidity of food assigning mechanical and moisture/gas barrier properties. Moreover, the grafting to chitosan of some functional molecules, like phenolic compounds or essential oils, gives antioxidant, antimicrobial, among others properties to chitosan. The addition of nanofillers to chitosan and other biopolymers improves the already mentioned required properties for food applications and can attribute electrical conductivity and magnetic properties for active and intelligent packaging. Electrical conductivity is a required property for the processing of food at low temperature using electric fields or for sensors application. © 2018 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Quorum Quenching and Microbial Control through Phenolic Extract of Eugenia Uniflora Fruits.

PubMed

Rodrigues, Adeline Conceição; Zola, Flávia Guimarães; Ávila Oliveira, Brígida D'; Sacramento, Nayara Thais Barbosa; da Silva, Elis Regina; Bertoldi, Michele Corrêa; Taylor, Jason Guy; Pinto, Uelinton Manoel

2016-10-01

We describe the characterization of the centesimal composition, mineral and phenolic content of Eugenia uniflora fruit and the determination of the antioxidant, antimicrobial and quorum quenching activities of the pulp phenolic extract. Centesimal composition was determined according to standard methods; trace elements were measured by total reflection X-ray fluorescence spectroscopy. The phenolic compounds were extracted by solid-phase chromatography and quantified by spectrophotometry. Antioxidant activity was determined by using 3 different methods. Antimicrobial activity was evaluated against a panel of foodborne microorganisms and antiquorum sensing activity in Chromobacterium violaceum was performed by measuring inhibition of quorum sensing dependent violacein production. The centesimal composition (per 100 g of pulp) was as follows: protein 3.68 ± 0.21 g, lipids 0.02 ± 0.03 g, carbohydrates 10.31 g and fiber 2.06 g. Trace elements (mg/g of pulp) were determined as: K 0.90, Ca 3.36, Fe 0.60, Zn 0.17, Cl 0.56, Cr 0.06, Ni 0.04, and Cu 0.07. The pulp is a source of phenolic compounds and presents antioxidant activity similar to other berries. The fruit phenolic extract inhibited all tested bacteria. We also found that the fruit phenolic extract at low subinhibitory concentrations inhibited up to 96% of violacein production in C. violaceum, likely due to the fruit's phenolic content. This study shows the contribution of E. uniflora phenolic compounds to the antioxidant, antimicrobial and the newly discovered quorum quenching activity, all of which could be used by the food and pharmaceutical industries to develop new functional products. © 2016 Institute of Food Technologists®.

Chemical characterization and bioactive properties of two aromatic plants: Calendula officinalis L. (flowers) and Mentha cervina L. (leaves).

PubMed

Miguel, María; Barros, Lillian; Pereira, Carla; Calhelha, Ricardo C; Garcia, Pablo A; Castro, MaÁngeles; Santos-Buelga, Celestino; Ferreira, Isabel C F R

2016-05-18

The chemical composition and bioactive properties of two plants (Calendula officinalis L. and Mentha cervina L.) were studied. Their nutritional value revealed a high content of carbohydrates and low fat levels, and very similar energy values. However, they presented different profiles in phenolic compounds and fatty acids; C. officinalis presented mainly glycosylated flavonols and saturated fatty acids, while M. cervina presented mainly caffeoyl derivatives and polyunsaturated fatty acids. M. cervina showed the highest concentration of phenolic compounds while C. officinalis presented higher amounts of sugars, organic acids and tocopherols. The highest antioxidant and cytotoxic activities were obtained for the hydromethanolic extract of M. cervina, which presented the lowest values of EC50 and exhibited cytotoxicity against the four tumor cell lines tested. Infusions showed no cytotoxicity for the tumor cell lines, and none of the extracts showed toxicity against non-tumor cells. This study contributes to expand the knowledge on both natural sources and therefore their use.

Composition and properties of virgin pistachio oils and their by-products from different cultivars.

PubMed

Ojeda-Amador, Rosa M; Fregapane, Giuseppe; Salvador, María Desamparados

2018-02-01

Pistachios (Pistacia vera) exhibit an interesting nutritional value, due to the high content of oleic acid and minor components with antioxidant and bioactive properties. This work aimed to characterize pistachio virgin oils and their partially defatted residual cakes, obtained from eight cultivars (Aegina, Avdat, Kastel, Kerman, Larnaka, Mateur, Napoletana, and Sirora). Interesting results on phenolics, tocopherols and antioxidant activity were observed, which were greatly affected by variety. Pistachio virgin oils are rich in healthy oleic acid (55-74%), phytosterols (3200-7600mg/kg) and γ-tocopherol (550-720mg/kg). A high content of phenolic compounds (8600-15000mg/kg gallic acid equivalents) and the corresponding antioxidant activities (12-46 and 155-496mmol/kg for DPPH and ORAC) of the residual cakes demonstrate their potential applications as functional ingredients and as rich sources of bioactive compounds. Moreover, virgin pistachio oils possess peculiar and pleasant sensory characteristics, contributing greater added value to the consumers compared to refined vegetable oils. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of baking and boiling on the nutritional and antioxidant properties of sweet potato [Ipomoea batatas (L.) Lam.] cultivars.

PubMed

Dincer, Cuneyt; Karaoglan, Mert; Erden, Fidan; Tetik, Nedim; Topuz, Ayhan; Ozdemir, Feramuz

2011-11-01

The effects of baking and boiling on the nutritional and antioxidant properties of three sweet potato cultivars (Beniazuma, Koganesengan, Kotobuki) cultivated in Turkey were investigated. The samples were analyzed for proximate composition, total phenolic content, ascorbic acid, β-carotene, antiradical activity, and free sugars. The dry matter, protein, and starch contents of the sweet potatoes were significantly changed by the treatments while the ash and crude fiber contents did not differ as significantly. The β-carotene contents of baked and boiled sweet potatoes were lower than those of fresh sweet potatoes; however, the total phenolic and ascorbic acid contents of the baked and boiled sweet potatoes were higher than those of the fresh samples. Generally, the antiradical activity of the sweet potatoes increased with the treatments. Sucrose, glucose, and fructose were quantified as free sugars in all fresh sweet potatoes; however, maltose was determined in the treated samples. In terms of the analyzed parameters, there were no explicit differences among the sweet potato cultivars.

An organic dye-polymer (phenol red-poly (vinyl alcohol)) composite architecture towards tunable -optical and -saturable absorption characteristics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sreedhar, Sreeja, E-mail: sreejasreedhar83@gmail.com; Muneera, C. I., E-mail: drcimuneera@hotmail.com; Illyaskutty, Navas

2016-05-21

Herein, we demonstrate that blending an organic dye (guest/filler), with a vinyl polymer (host template), is an inexpensive and simple approach for the fabrication of multifunctional photonic materials which could display an enhancement in the desirable properties of the constituent materials and, at the same time provide novel synergistic properties for the guest-host system. A new guest-host nanocomposite system comprising Phenol Red dye and poly (vinyl alcohol) as guest and host template, respectively, which exhibits tunable optical characteristics and saturable absorption behavior, is introduced. The dependence of local electronic environment provided by the polymer template and the interactions of themore » polymer molecules with the encapsulated guest molecules on the observed optical/nonlinear absorption behavior is discussed. An understanding of the tunability of the optical/ photophysical processes, with respect to the filler content, as discussed herein could help in the design of improved optical materials for several photonic device applications like organic light emitting diodes and saturable absorbers.« less

Scientific validation of synergistic antioxidant effects in commercialised mixtures of Cymbopogon citratus and Pterospartum tridentatum or Gomphrena globosa for infusions preparation.

PubMed

Roriz, Custódio Lobo; Barros, Lillian; Carvalho, Ana Maria; Santos-Buelga, Celestino; Ferreira, Isabel C F R

2015-10-15

Pterospartum tridentatum (L.) Willk., Gomphrena globosa L. and Cymbopogon citratus (DC) Stapf. are examples of medicinal plants with antioxidant properties on their own, but that can be improved when mixed. In the present work, the antioxidant activity and phenolic compounds were determined in the infusions prepared from the individual plants, and from mixtures of these plants in different proportions. P. tridentatum > C. citratus > G. globosa was the order observed for antioxidant efficacy, which can be related to their different composition in phenolic compounds. Synergism was the main effect observed among the tested mixtures, mainly for the infusions prepared from the plants in proportion 40%:60% (either P. tridentatum and C. citratus; or G. globosa and C. citratus). The infusion obtained with 40% of P. tridentatum and 60% of C. citratus gave the highest antioxidant properties. The present study validates the commercialisation of the studied plants combined in specific proportions. Copyright © 2015 Elsevier Ltd. All rights reserved.

Rheological and stability aspects of dry and hydrothermally heat treated aleurone-rich wheat milling fraction.

PubMed

Bucsella, Blanka; Takács, Ágnes; von Reding, Walter; Schwendener, Urs; Kálmán, Franka; Tömösközi, Sándor

2017-04-01

Novel aleurone-rich wheat milling fraction developed and produced on industry scale is investigated. The special composition of the novel flour with high protein, dietary fiber and fat content results in a unique combination of the mixing and viscosity properties. Due to the high lipid concentration, the fraction is exposed to fast rancidity. Dry heat (100°C for 12min) and hydrothermal treatment processes (96°C for 6min with 0-20 L/h steam) were applied on the aleurone-rich flour to modify the technological properties. The chemical, structural changes; the extractability of protein, carbohydrate and phenolic components and the rheological characteristics of the flours were evaluated. The dry treated flour decreased protein and carbohydrate extractability, shortened dough development time, reduced gel strength and enhanced the gelling ability. Hydrothermal treatment caused changes in the phenolic content improved the dough stability and -resistance. Heat treatment processes were able to extend the stability of the flour. Copyright © 2016 Elsevier Ltd. All rights reserved.

Evaluation of productivity and antioxidant profile of solid-state cultivated macrofungi Pleurotus albidus and Pycnoporus sanguineus.

PubMed

Gambato, Gabriela; Todescato, Kelly; Pavão, Elisa Maria; Scortegagna, Angélica; Fontana, Roselei Claudete; Salvador, Mirian; Camassola, Marli

2016-05-01

The aim of this study was to investigate the production profile of Pleurotus albidus and Pycnoporus sanguineus on different waste substrates containing natural phenolics, and also to investigate whether phenolic-rich substrates can improve the phenolic content of these macrofungi. The medium formulated with Pinus sp. sawdust (PSW) made possible the highest yields (2.62±0.73%) of P. sanguineus. However, the supplementation of PSW with apple waste (AW) resulted in better P. albidus yields (23.94±2.92%). The results indicated that the substrate composition affected macrofungi production, also the chemical composition and the presence of phenolic compounds in the production media influence phenolic content and antioxidant activity in macrofungi. Copyright © 2016 Elsevier Ltd. All rights reserved.

DEVELOPMENT OF FLEXIBLE INSULATION FOR SOLID PROPELLANT ROCKET MOTOR CASES

DTIC Science & Technology

acrylonitrile-phenol furfural -asbestos composition. Other promising materials which are reported are based on two types of liquid butadiene/styrene cbers. The...This material was based on a butadiene/acrylonitrile-phenol furfural -asbestos composition. Other promising materials which are reported are based on two

Antioxidant activity of commercial buckwheat flours and their free and bound phenolic compositions

USDA-ARS?s Scientific Manuscript database

Buckwheat flours (Whole, Farinetta, Supreme, and Fancy) were investigated for their compositions, free and bound phenolic contents, antioxidant activities, and flavonoid contents using spectrophotometer and LC-ESI-IT- MS (LC-MS). Farinetta flour contained the highest oil, protein, and free and boun...

Influence of the temperature and oxygen exposure in red Port wine: A kinetic approach.

PubMed

Oliveira, Carla Maria; Barros, António S; Silva Ferreira, António César; Silva, Artur M S

2015-09-01

Although phenolics are recognized to be related with health benefits by limiting lipid oxidation, in wine, they are the primary substrates for oxidation resulting in the quinone by-products with the participation of transition metal ions. Nevertheless, high quality Port wines require a period of aging in either bottle or barrels. During this time, a modification of sensory properties of wines such as the decrease of astringency or the stabilization of color is recognized to phenolic compounds, mainly attributed to anthocyanins and derived pigments. The present work aims to illustrate the oxidation of red Port wine based on its phenolic composition by the effect of both thermal and oxygen exposures. A kinetic approach toanthocyanins degradation was also achieved. For this purpose a forced red Port wine aging protocol was performed at four different storage temperatures, respectively, 20, 30, 35 and 40°C, and two adjusted oxygen saturation levels, no oxygen addition (treatment I), and oxygen addition (treatment II). Three hydroxycinnamic esters, three hydroxycinnamic acids, three hydroxybenzoic acids, two flavan-3-ols, and six anthocyanins were quantitated weekly during 63days, along with oxygen consumption. The most relevant phenolic oxidation markers were anthocyanins and catechin-type flavonoids, which had the highest decreases during the thermal and oxidative red Port wine process. Both temperature and oxygen treatments affected the rate of phenolic degradation. In addition, temperature seems to influence mostly the phenolics kinetic degradation. Copyright © 2015 Elsevier Ltd. All rights reserved.

A Fe3O4/FeAl2O4 composite coating via plasma electrolytic oxidation on Q235 carbon steel for Fenton-like degradation of phenol.

PubMed

Wang, Jiankang; Yao, Zhongping; Yang, Min; Wang, Yajing; Xia, Qixing; Jiang, Zhaohua

2016-08-01

The Fe3O4/FeAl2O4 composite coatings were successfully fabricated on Q235 carbon steel by plasma electrolytic oxidation technique and used to degrade phenol by Fenton-like system. XRD, SEM, and XPS indicated that Fe3O4 and FeAl2O4 composite coating had a hierarchical porous structure. The effects of various parameters such as pH, phenol concentration, and H2O2 dosage on catalytic activity were investigated. The results indicated that with increasing of pH and phenol content, the phenol degradation efficiency was reduced significantly. However, the degradation rate was improved with the addition of H2O2, but dropped with further increasing of H2O2. Moreover, 100 % removal efficiency with 35 mg/L phenol was obtained within 60 min at 303 K and pH 4.0 with 6.0 mmol/L H2O2 on 6-cm(2) iron oxide coating. The degradation process consisted of induction period and rapid degradation period; both of them followed pseudo-first-order reaction. Hydroxyl radicals were the mainly oxidizing species during phenol degradation by using n-butanol as hydroxyl radical scavenger. Based on Fe leaching and the reaction kinetics, a possible phenol degradation mechanism was proposed. The catalyst exhibited excellent stability.

Technology development for phosphoric acid fuel cell powerplant, phase 2

NASA Technical Reports Server (NTRS)

Christner, L.

1979-01-01

A technique for producing an acid inventory control member by spraying FEP onto a partially screened carbon paper backing is discussed. Theoretical analysis of the acid management indicates that the vapor composition of 103% H3PO4 is approximately 1.0 ppm P4O10. An SEM evaluation of corrosion resistance of phenolic resins and graphite/phenolic resin composites in H3PO4 at 185 C shows specific surface etching. Carbonization of graphite/phenolic bipolar plates is achieved without blistering.

Gelled compositions and well treating

DOE Office of Scientific and Technical Information (OSTI.GOV)

Swanson, B.L.

1982-04-06

Gelled compositions are disclosed suitable as fracture fluids and water diversion agents comprising water, a polymeric viscosifier, an aldehyde component, and at least one phenolic component such as resorcinol, catechol, and the like, as well as selected oxidized phenolic materials such as 1,4-benzoquinone of natural or synthetic origin and natural and modified tannins. The gelled compositions can additionally contain gel stabilizers and chemical buffering agents.

Characterisation of extra virgin olive oils from Galician autochthonous varieties and their co-crushings with Arbequina and Picual cv.

PubMed

Reboredo-Rodríguez, P; González-Barreiro, C; Cancho-Grande, B; Fregapane, G; Salvador, M D; Simal-Gándara, J

2015-06-01

The current trend of the olive oil market is the production of high quality extra from traditional minor olive varieties with peculiar and differentiated characteristics (especially with respect to the aromatic and phenolic composition). In this way, the interest of Galician oil producers (NW Spain) in recovering old autochthonous Local olive fruits has increased substantially in recent years. In order to investigate the potential of the Local olives by either producing high quality monovarietal oils or mixing with the most widespread olives in Galicia (Arbequina and Picual cv.), quality indices, and fatty acid composition as well as volatile and phenolic profiles were determined and compared. All EVOOs studied in this work can be considered as "extra virgin olive oil" due to quality indices fell within the ranges established in legislation. Picual and Local olive oils as well as those resulting from their co-crushing reach values which are required by EU legislation to add the specific health claim on the oil label. Co-crushing Picual:Local (80:20) provided a significant enhancement of grass and apple nuances and a decrease of banana notes with respect to Picual oils. The co-crushing process improved sensory and health properties of Picual extra virgin olive oils. The effect of co-crushing on phenolics, ester volatiles and banana nuances cannot be easily modulated, contrary to quality indices and fatty acid composition, both changing linearly in strict correlation with the fruit mass ratio. Copyright © 2014 Elsevier Ltd. All rights reserved.

VISCOSITY AND BINDER COMPOSITION EFFECTS ON TYROSINASE-BASED CARBON PASTE ELECTRODE FOR DETECTION OF PHENOL AND CATECHOL

EPA Science Inventory

The systematic study of the effect of binder viscosity on the sensitivity of a tyrosinase-based carbon paste electrode (CPE) biosensor for phenol and catechol is reported. Silicon oil binders with similar (polydimethylsiloxane) chemical composition were used to represent a wid...

Effects of roasting temperature and duration on fatty acid composition, phenolic composition, Maillard reaction degree and antioxidant attribute of almond (Prunus dulcis) kernel.

PubMed

Lin, Jau-Tien; Liu, Shih-Chun; Hu, Chao-Chin; Shyu, Yung-Shin; Hsu, Chia-Ying; Yang, Deng-Jye

2016-01-01

Roasting treatment increased levels of unsaturated fatty acids (linoleic, oleic and elaidic acids) as well as saturated fatty acids (palmitic and stearic acids) in almond (Prunus dulcis) kernel oils with temperature (150 or 180 °C) and duration (5, 10 or 20 min). Nonetheless, higher temperature (200 °C) and longer duration (10 or 20 min) roasting might result in breakdown of fatty acids especially for unsaturated fatty acids. Phenolic components (total phenols, flavonoids, condensed tannins and phenolic acids) of almond kernels substantially lost in the initial phase; afterward these components gradually increased with roasting temperature and duration. Similar results also observed for their antioxidant activities (scavenging DPPH and ABTS(+) radicals and ferric reducing power). The changes of phenolic acid and flavonoid compositions were also determined by HPLC. Maillard reaction products (estimated with non-enzymatic browning index) also increased with roasting temperature and duration; they might also contribute to enhancing the antioxidant attributes. Copyright © 2015 Elsevier Ltd. All rights reserved.

A different approach for the analysis of grapes: Using the skin as sensing element.

PubMed

Muñoz, Raquel; García-Hernández, Celia; Medina-Plaza, Cristina; García-Cabezón, Cristina; Fernández-Escudero, J A; Barajas, Enrique; Medrano, Germán; Rodriguez-Méndez, María Luz

2018-05-01

In this work, an alternative method to monitor the phenolic maturity of grapes was developed. In this approach, the skins of grapes were used to cover the surface of carbon paste electrodes and the voltammetric signals obtained with the skin-modified sensors were used to obtain information about the phenolic content of the skins. These sensors could easily detect differences in the phenolic composition of different Spanish varieties of grapes (Mencía, Prieto Picudo and Juan García). Moreover, sensors were able to monitor changes in the phenolic content throughout the ripening process from véraison until harvest. Using PLS-1 (Partial Least Squares), correlations were established between the voltammetric signals registered with the skin-modified sensors and the phenolic content measured by classical methods (Glories or Total Polyphenol Index). PLS-1 models provided additional information about Brix degree, density or sugar content, which usually used to establish the harvesting date. The quality of the correlations was influenced by the maturation process and the structural and mechanical skin properties. Thus the skin sensors fabricated with Juan García and Prieto Picudo grapes (that showed faster polyphenolic maturation and a higher amount of extractable polyphenols than Mencía), showed good correlations and therefore could be used to monitor the ripening. Copyright © 2018 Elsevier Ltd. All rights reserved.

Magnetic heterogeneous catalytic ozonation: a new removal method for phenol in industrial wastewater

PubMed Central

2014-01-01

In this study, a new strategy in catalytic ozonation removal method for degradation of phenol from industrial wastewater was investigated. Magnetic carbon nano composite as a novel catalyst was synthesized, characterized and then used in the catalytic ozonation process (COP) and compared with the single ozonation process (SOP). The influential parameters were all investigated. The results showed that the removal efficiency of phenol and COD (chemical oxygen demand) in COP (98.5%, 69.8%) was higher than those of SOP (78.7%, 50.5%) and the highest catalytic potential was achieved at optimal neutral pH. First order modeling demonstrated that the reactions were dependent on the concentration of catalyst, with kinetic constants varying from 0.023 1/min (catalyst = 0 g/L) to 0.071 1/min (catalyst = 4 g/L), whereby the optimum dosage of catalyst was found to be 2 g/L. Furthermore, the catalytic properties of the catalyst remained almost unchanged after 5-time reuse. The results regarding the biodegradability of the effluent showed that a 5-min reaction time in COP reduced the concentrations of phenol and COD to the acceptable levels for the efficient post-treatment in the SBR in a 4-h cycle period. Finally, this combined system is proven to be a technically effective method for treating phenolic contaminants. PMID:24572145

DOE Office of Scientific and Technical Information (OSTI.GOV)

Arman, B.; An, Q.; Luo, S. N.

We investigate with nonreactive molecular dynamics simulations the dynamic response of phenolic resin and its carbon-nanotube (CNT) composites to shock wave compression. For phenolic resin, our simulations yield shock states in agreement with experiments on similar polymers except the “phase change” observed in experiments, indicating that such phase change is chemical in nature. The elastic–plastic transition is characterized by shear stress relaxation and atomic-level slip, and phenolic resin shows strong strain hardening. Shock loading of the CNT-resin composites is applied parallel or perpendicular to the CNT axis, and the composites demonstrate anisotropy in wave propagation, yield and CNT deformation. Themore » CNTs induce stress concentrations in the composites and may increase the yield strength. Our simulations indicate that the bulk shock response of the composites depends on the volume fraction, length ratio, impact cross-section, and geometry of the CNT components; the short CNTs in current simulations have insignificant effect on the bulk response of resin polymer.« less

Effect of flash release treatment on phenolic extraction and wine composition.

PubMed

Morel-Salmi, Cécile; Souquet, Jean-Marc; Bes, Magali; Cheynier, Véronique

2006-06-14

The flash release (FR) process, consisting of rapidly heating the grapes and then applying strong vacuum, has been proposed to increase the polyphenol content of red wines. Its impact on polyphenol extraction kinetics and on the polyphenol composition of red juice and wines was studied over two seasons on different grape varieties (Grenache, Mourvedre, Carignan). The FR process allows fast extraction of all phenolic compounds (hydroxycinnamic acids, flavonols, anthocyanins, catechins, proanthocyanidins) and can be used to produce polyphenol-enriched grape juices. However, the concentration of all polyphenols dramatically decreased throughout fermentation when pressing was achieved immediately after FR. The FR wines made with pomace maceration were also enriched in polyphenols compared to the corresponding control wines. Increasing the duration of high-temperature exposure in the FR treatment further increased extraction of phenolic compounds but also accelerated their conversion to derived species. The tannin-to-anthocyanin ratio was particularly low in the wine fermented in the liquid phase, higher after FR than in the control, and even higher after longer heating. FR resulted in an increased tannin-to-anthocyanin ratio and an increased conversion of anthocyanins to tannin-anthocyanin adducts showing the same color properties as anthocyanins. The tannin-to-anthocyanin ratio was particularly low in the wine fermented in the liquid phase that also contained larger amounts of orange sulfite bleaching-resistant pigments.

Gum arabic based composite edible coating on green chillies

NASA Astrophysics Data System (ADS)

Valiathan, Sreejit; Athmaselvi, K. A.

2018-04-01

Green chillies were coated with a composite edible coating composed of gum arabic (5%), glycerol (1%), thyme oil (0.5%) and tween 80 (0.05%) to preserve the freshness and quality of green chillies and thus reduce the cost of preservation. In the present work, the chillies were coated with the composite edible coating using the dipping method with three dipping times (1, 3 and 5 min). The physicochemical parameters of the coated and control chillies stored at room temperature (28±2ºC) were evaluated at regular intervals of storage. There was a significant difference (p≤0.05) in the physicochemical properties between the control chillies and coated chillies with 1, 3 and 5 min dipping times. The coated green chillies showed significantly (p≤0.05) lower weight loss, phenolic acid production, capsaicin production and significantly (p≤0.05) higher retention of ascorbic acid, total chlorophyll content, colour, firmness and better organoleptic properties. The composite edible coating of gum arabic and thyme oil with 3 min dipping was effective in preserving the desirable physico-chemical and organoleptic properties of the green chillies up to 12 days, compared to the uncoated chillies that had a shelf life of 6 days at room temperature.

Effect of gas release in hot molding on flexural strength of composite friction brake

NASA Astrophysics Data System (ADS)

Rusdja, Andy Permana; Surojo, Eko; Muhayat, Nurul; Raharjo, Wijang Wisnu

2018-02-01

Composite friction brake is a vital part of braking system which serves to reduce the speed of vehicle. To fulfill the requirement of brake performance, composite friction brake must have friction and mechanical characteristic as required. The characteristics of composite friction brake are affected by brake material formulation and manufacturing parameter. In the beginning of hot molding, intermittent hot pressing was carried out to release the gases that consist of ammonia gas and water vapor. In composite friction brake, phenolic resin containing hexamethylenetetramine (HMTA) is often used as a binder. During hot molding, the reaction of phenolic resin and HMTA forms ammonia gas. Hot molding also generates water vapor because raw materials absorb moisture from environment when they are placed in storage. The gas release in hot molding is supposed affecting mechanical properties because it avoid entrapped gas in composite, so that this research investigated effect of gas release on flexural strength. Manufacturing of composite specimen was carried out as follow: mixing of raw materials, cold molding, and hot molding. In this research, duration of intermittent hot pressing and number of gas release were varied. The flexural strength of specimen was measured using three point bending test. The results showed that flexural strength specimens that were manufactured without gas release, using 4 times gas release with intermittent hot pressing for 5 and 10 seconds were not remarkably different. Conversely, hot molding using 4 times gas release with intermittent hot pressing for 15 seconds decreased flexural strength of composite. Hot molding using 2, 4, and 8 times gas release with intermittent hot pressing for 10 seconds also had no effect on increasing flexural strength. Increasing of flexural strength of composite was obtained only by using 6 times gas release with intermittent hot pressing for 10 seconds.

Inhibitory effects of benzimidazole containing new phenolic Mannich bases on human carbonic anhydrase isoforms hCA I and II.

PubMed

Gul, Halise Inci; Yazici, Zehra; Tanc, Muhammet; Supuran, Claudiu T

2016-12-01

New phenolic mono and bis Mannich bases incorporating benzimidazole, such as 2-(aminomethyl)-4-(1H-benzimidazol-2-yl)phenol and 2,6-bis(aminomethyl)-4-(1H-benzimidazol-2-yl)phenol were synthesized starting from 4-(1H-benzimidazol-2-yl)phenol. Amines used for the synthesis included dimethylamine, pyrrolidine, piperidine, N-methylpiperazine and morpholine. The CA inhibitory properties of these compounds were tested on the human carbonic anhydrase (CA, EC 4.2.1.1) isoforms hCA I and hCA II. These new compounds, as many phenols show moderate CA inhibitory properties.

Engineering phenolics metabolism in the grasses using transcription factors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grotewold, Erich

2013-07-26

The economical competitiveness of agriculture-derived biofuels can be significantly enhanced by increasing biomass/acre yields and by furnishing the desired carbon balance for facilitating liquid fuel production (e.g., ethanol) or for high-energy solid waste availability to be used as biopower (e.g., for electricity production). Biomass production and carbon balance are tightly linked to the biosynthesis of phenolic compounds, which are found in crops and in agricultural residues either as lignins, as part of the cell wall, or as soluble phenolics which play a variety of functions in the biology of plants. The grasses, in particular maize, provide the single major sourcemore » of agricultural biomass, offering significant opportunities for increasing renewable fuel production. Our laboratory has pioneered the use of transcription factors for manipulating plant metabolic pathways, an approach that will be applied here towards altering the composition of phenolic compounds in maize. Previously, we identified a small group of ten maize R2R3-MYB transcription factors with all the characteristics of regulators of different aspects of phenolic biosynthesis. Here, we propose to investigate the participation of these R2R3-MYB factors in the regulation of soluble and insoluble maize phenolics, using a combination of over-expression and down-regulation of these transcription factors in transgenic maize cultured cells and in maize plants. Maize cells and plants altered in the activity of these regulatory proteins will be analyzed for phenolic composition by targeted metabolic profiling. Specifically, we will I) Investigate the effect of gain- and loss-of-function of a select group of R2R3-MYB transcription factors on the phenolic composition of maize plants and II) Identify the biosynthetic genes regulated by each of the selected R2R3-MYB factors. While a likely outcome of these studies are transgenic maize plants with altered phenolic composition, this research will significantly contribute to understanding how different branches of the phenolic biosynthetic grid are regulated. Given the conservation of the selected regulators in other grasses, results derived from this project are likely to provide important tools for the manipulation of phenolic compounds in other emerging biomass producers (e.g., switchgrass or miscanthus), either through conventional breeding techniques (e.g., marker-assisted breeding) or by using transgenic approaches.« less

Phenolic composition of pomegranate peel extracts using an liquid chromatography-mass spectrometry approach with silica hydride columns.

PubMed

Young, Joshua E; Pan, Zhongli; Teh, Hui Ean; Menon, Veena; Modereger, Brent; Pesek, Joseph J; Matyska, Maria T; Dao, Lan; Takeoka, Gary

2017-04-01

The peels of different pomegranate cultivars (Molla Nepes, Parfianka, Purple Heart, Wonderful and Vkunsyi) were compared in terms of phenolic composition and total phenolics. Analyses were performed on two silica hydride based stationary phases: phenyl and undecanoic acid columns. Quantitation was accomplished by developing a liquid chromatography with mass spectrometry approach for separating different phenolic analytes, initially in the form of reference standards and then with pomegranate extracts. The high-performance liquid chromatography columns used in the separations had the ability to retain a wide polarity range of phenolic analytes, as well as offering beneficial secondary selectivity mechanisms for resolving the isobaric compounds, catechin and epicatechin. The Vkunsyi peel extract had the highest concentration of phenolics (as determined by liquid chromatography with mass spectrometry) and was the only cultivar to contain the important compound punicalagin. The liquid chromatography with mass spectrometry data were compared to the standard total phenolics content as determined by using the Folin-Ciocalteu assay. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Anomalous swelling behavior of FM 5055 carbon phenolic composite

NASA Technical Reports Server (NTRS)

Stokes, E. H.

1992-01-01

The swelling response of a typical carbon phenolic composite was measured in the three primary material directions. The data obtained sugrest that at low and high relative humidities the incremental increase in moisture absorption can be attributed primarily to the resin. At intermediate relative humidities, the water is moving largely into the carbonized fibers.

Comparative Study of Phenolic Profile, Antioxidant Capacity, and Color-composition Relation of Roselle Cultivars with Contrasting Pigmentation.

PubMed

Camelo-Méndez, Gustavo A; Jara-Palacios, M José; Escudero-Gilete, M Luisa; Gordillo, Belén; Hernanz, Dolores; Paredes-López, Octavio; Vanegas-Espinoza, Pablo E; Del Villar-Martínez, Alma A; Heredia, Francisco J

2016-03-01

Roselle is a plant that accumulates anthocyanins significantly, hence its importance as food coloring and as a source of antioxidant compounds for human health. This study was aimed to determine phenolic composition and antioxidant capacity of methanolic extracts, and beverages obtained from native roselle cultivars in Mexico (Negra, Sudan, Rosa and Blanca) with different degrees of pigmentation, and to establish the color-composition relationship. Chromatographic methods were used to determine phenolic compounds: flavanols, flavonols, benzoic, hibiscus and phenolic acids as well as two main anthocyanins (cyanidin 3-sambubioside and delphinidin 3-sambubioside). The antioxidant capacity was evaluated by ABTS and FRAP assays. Tristimulus colorimetry showed to be a useful technique to determine the color-composition relationship, leading to equations that allowed to predict anthocyanin content of roselle (R > 0.84). Also, a stepwise linear discriminant analysis (SLDA) was developed in order to classify roselle cultivars. The obtained mathematical model could be an important tool to be used in colorimetric characterization of functional compounds used in food processing.

Effect of phenol on the nitrogen removal performance and microbial community structure and composition of an anammox reactor.

PubMed

Pereira, Alyne Duarte; Leal, Cíntia Dutra; Dias, Marcela França; Etchebehere, Claudia; Chernicharo, Carlos Augusto L; de Araújo, Juliana Calabria

2014-08-01

The effects of phenol on the nitrogen removal performance of a sequencing batch reactor (SBR) with anammox activity and on the microbial community within the reactor were evaluated. A phenol concentration of 300 mg L(-1) reduced the ammonium-nitrogen removal efficiency of the SBR from 96.5% to 47%. The addition of phenol changed the microbial community structure and composition considerably, as shown by denaturing gradient gel electrophoresis and 454 pyrosequencing of 16S rRNA genes. Some phyla, such as Proteobacteria, Verrucomicrobia, and Firmicutes, increased in abundance, whereas others, such as Acidobacteria, Chloroflexi, Planctomycetes, GN04, WS3, and NKB19, decreased. The diversity of the anammox bacteria was also affected by phenol: sequences related to Candidatus Brocadia fulgida were no longer detected, whereas sequences related to Ca. Brocadia sp. 40 and Ca. Jettenia asiatica persisted. These results indicate that phenol adversely affects anammox metabolism and changes the bacterial community within the anammox reactor. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effect of addition of commercial grape seed tannins on phenolic composition, chromatic characteristics, and antioxidant activity of red wine.

PubMed

Neves, Ana C; Spranger, Maria I; Zhao, Yuqing; Leandro, Maria C; Sun, Baoshan

2010-11-24

The effect of addition of grape seed tannins on the phenolic composition, chromatic characteristics, and antioxidant activity of red wine was studied. Two highly pure commercial grape seed tannins (GSE100 and GSE300) were selected, and their phenolic compositions were determined. Two types of red wines were made with Castelão/Tinta Miúda (3/2, w/w) grapevine varieties by fermentation on skin using two different maceration times, which correspond to the wines rich and poor in polyphenols, respectively. Each of these wines was used for experimentation with the addition of GSE100 and GSE300 before and immediately after alcoholic fermentation. Phenolic composition, chromatic characteristics, and antioxidant activity of the finished red wines were analyzed by HPLC-DAD, CIElab 76 convention, and DPPH radical test, respectively. The results showed that the addition of grape seed tannins had obvious effects of increasing color intensity and antioxidant activity only in the wines poor in polyphenols. Although GSE300 contained much higher amounts of di- and trimer procyanidins and a lower amount of polymeric proanthocyanidins, it provided effects of increasing the color intensity and antioxidant activity of the wines poor in polyphenols similar to those of GSE100. Furthermore, GSE100 released more gallic acid to wines than GSE300, although no gallic acid was detected in GSE100. Tannins added after alcoholic fermentation had a better effect on phenolic composition of red wine than tannins added before alcoholic fermentation.

Effect of filler content on the properties of expanded- graphite-based composite bipolar plates for application in polymer electrolyte membrane fuel cells

NASA Astrophysics Data System (ADS)

Masand, Aakash; Borah, Munu; Pathak, Abhishek K.; Dhakate, Sanjay R.

2017-09-01

Minimization of the weight and volume of a hydrogen-based PEM fuel cell stack is an essential area of research for the development and commercialization of PEMFCs for various applications. Graphite-based composite bipolar plates have significant advantages over conventional metallic bipolar plates due to their corrosion resistivity and low cost. On the other hand, expanded graphite is seen to be a potential candidate for facilitating the required electrical, thermal and mechanical properties of bipolar plates with a low density. Therefore, in the present study, the focus is on minimization of the high loading of graphite and optimizes its composition to meet the target properties of bipolar plates as per the USDOE target. Three types of expanded graphite (EG)-phenolic-resin-based composite bipolar plates were developed by partially replacing the expanded graphite content with natural graphite (NG) and carbon black as an additional filler. The three types of composite plate with the reinforcing constituent ratio EG:NG:R (25:25:50) give a bending strength of 49 MPa, a modulus of ~6 GPa, electrical conductivity  >100 S cm-1, a shore hardness of 55 and a bulk density of 1.55 g/cc. The 50 wt% loading of resin is sufficient to wet the 50 wt% filler content in the composite plate. This study gives an insight into using hybrid reinforcements in order to achieve the desired properties of bipolar plates.

Distribution of free amino acids, flavonoids, total phenolics, and antioxidative activities of Jujube (Ziziphus jujuba) fruits and seeds harvested from plants grown in Korea.

PubMed

Choi, Suk-Hyun; Ahn, Jun-Bae; Kozukue, Nobuyuki; Levin, Carol E; Friedman, Mendel

2011-06-22

Fruit pulp and seeds from the jujube plant possess nutritional and medicinal properties. The bioactive components have been shown to vary both with cultivar and with growing conditions. Most studies report the components of varieties from China. We measured free amino acid, individual phenolic, and total phenolic content, and antioxidative activities in three jujube fruit pulp extracts from Boeun-deachu, Mechu, and Sanzoin cultivars and two seed extracts (Mechu and Sanzoin) from plants grown in Korea. In g/100 g dry weight, total free amino acid content measured by ion-exchange chromatography ranged from 5.2 to 9.8 in the pulp and from 4.0 to 5.3 in the seed. Total phenolic content measured by Folin-Ciocalteu ranged from 1.1 to 2.4 in the pulp and from 3.6 to 4.6 in the seed. Flavonoids were measured by HPLC and ranged from 0.7 to 1.8 in the pulp and from 3.2 to 4.0 in the seed. Flavonoids were identified by HPLC elution position and UV/vis and mass spectra. Fruits contained the following flavonoids: procyanidin B2, epicatechin, quercetin-3-O-rutinoside (Q-3-R), quercetin-3-O-galactoside (Q-3-G), kaempferol-glucosyl-rhamnoside (K-G-R), and two unidentified compounds. Seeds contained the following flavonoids: saponarin, spinosin, vitexin, swertish, 6'''-hydroxybenzoylspinosin (6'''-HBS), 6'''-feruloylspinosin (6'''-FS), and one unidentified substance. Dimensions and weights of the fresh fruit samples affected phenolic content. The distribution of the individual flavonoids among the different samples varied widely. Data determined by the FRAP antioxidative assay were well correlated with total phenolic content. In a departure from other studies, data from the DPPH free radical assay were not correlated with FRAP or with any of the measured compositional parameters. Because individual jujube flavonoids are reported to exhibit different health-promoting effects, knowledge of the composition and concentration of bioactive compounds of jujube products can benefit consumers.

Peel effects on phenolic composition, antioxidant activity, and making of pomegranate juice and wine.

PubMed

Wasila, Humaira; Li, Xuan; Liu, Linwei; Ahmad, Imran; Ahmad, Sajjad

2013-08-01

Pomegranate peel was used in juicing to find out its effects on the juice products' (storable juice and wine) sensory property, polyphenols composition, and antioxidant ability. Macroporous resin was used to purify the polyphenols, and 6 different in vitro assays were used to comprehensively determine the antioxidant activity of each. The results showed that juicing with peel made the juice bitter and astringent, but contributed better sensory quality to wine. Peel contributed higher total polyphenols and flavonoids, but lower anthocyanins to the juice products, and caused the phenolics content to fluctuate more dramatically during making wine than the storable juice. Polyphenols purified from the juice products containing peel showed higher total reducing ability and 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid radical elimination abilities, but their clearance activity of hydroxyl radicals was not positive, and their superoxide anion radical elimination ability showed no significant difference when compared to polyphenols purified from juice products without peel. © 2013 Institute of Food Technologists®

Characterization of the crosslinking reaction in high performance phenolic resins

NASA Astrophysics Data System (ADS)

Patel, Jigneshkumar; Zou, Guo Xiang; Hsu, Shaw Ling; university of massachusetts/Polymer science; Engineering Team

In this study, a combination of thermal analysis, infrared spectroscopy (near and mid) in conjunction with low field NMR, was used to characterize the crosslinking reaction involving phenol formaldehyde resin and a crosslinking agent, Hexamethylenetetramine (HMTA). The strong hydrogen bonds in the resin and the completely crystalline HMTA (Tm = 280 °C) severely hamper the crosslinking process. Yet the addition of a small amount of plasticizer can induce a highly efficient crosslinking reaction to achieve the desired mechanical properties needed in a number of high performance organic-inorganic composites. The infrared spectroscopy clarifies the dissolution process of the crystalline crosslinker and the specific interactions needed to achieve miscibility of the reactants. The thermal analysis enabled us to follow the changing mobility of the system as a function of temperature. The low field NMR with the T1 inverse recovery technique allowed us to monitor the crosslinking process directly. For the first time, it is now possible to identify the functionality of the plasticizer and correlate the crosslinked structure achieved to the macroscopic performance needed for high performance organic-inorganic composites.

Application of slightly acidic electrolyzed water for decontamination of stainless steel surfaces in animal transport vehicles.

PubMed

Ni, Li; Zheng, Weichao; Zhang, Qiang; Cao, Wei; Li, Baoming

2016-10-01

The effectiveness of slightly acidic electrolyzed water (SAEW) in reducing Escherichia coli, Salmonella typhimurim, Staphylococcus aureus or bacterial mixtures on stainless steel surfaces was evaluated and compared its efficacy with composite phenol solution for reducing total aerobic bacteria in animal transport vehicles. Stainless steel surfaces were inoculated with these strains individually or in a mixture, and sprayed with SAEW, composite phenol, or alkaline electrolyzed water for 0.5, 1, 1.5 and 2min. The bactericidal activity of SAEW increased with increasing available chlorine concentration and spraying duration. The SAEW solution of 50mgl -1 of available chlorine concentration showed significantly higher effectiveness than composite phenol in reducing the pathogens on stainless steel surfaces (P<0.05). Complete inactivation of pathogens on stainless steel surfaces were observed after treatment with alkaline electrolyzed water followed by SAEW at 50mgl -1 of available chlorine concentration for 2min or alkaline electrolyzed water treatment followed by SAEW treatment at 90mgl -1 of available chlorine concentration for 0.5min. The efficacy of SAEW in reducing total aerobic bacteria in animal transport vehicles was also determined. Vehicles in the disinfection booth were sprayed with the same SAEW, alkaline electrolyzed water and composite phenol solutions using the automatic disinfection system. Samples from vehicle surfaces were collected with sterile cotton swabs before and after each treatment. No significant differences in bactericidal efficiency were observed between SAEW and composite phenol for reducing total aerobic bacteria in the vehicles (P>0.05). SAEW was also found to be more effective when used in conjunction with alkaline electrolyzed water. Results suggest that the bactericidal efficiency of SAEW was higher than or equivalent to that of composite phenol and SAEW may be used as effective alternative for reducing microbial contamination of animal transport vehicles. Copyright © 2016 Elsevier B.V. All rights reserved.

LC-MS identification and preparative HPLC isolation of Frankenia pulverulenta phenolics with antioxidant and neuroprotective capacities in PC12 cell line.

PubMed

Ben Mansour, Rim; Wided, Megdiche Ksouri; Cluzet, Stéphanie; Krisa, Stéphanie; Richard, Tristan; Ksouri, Riadh

2017-12-01

Frankenia pulverulenta L. (Frankeniaceae) is a medicinal species with carminative, analgesic and antiviral properties. However, phytochemical investigations, antioxidant and neuroprotective capacities of this plant remain unclear. This work assesses the phenolic composition of F. pulverulenta shoot and root and evaluates their antioxidant and neuroprotective capacities. Successive fractionation of F. pulverulenta shoot and root using 6 solvents were used. Antioxidant capacity of these fractions was assessed through four in vitro tests (DPPH, ABTS, Fe-chelating activity and ORAC). Phenolic identification, purification as well as neuroprotective activity of ethyl acetate (EtOAc) fraction and purified molecules were assessed. Among the tested fractions, EtOAc shoot and root fractions possessed considerable phenolic contents (383 and 374 mg GAE/g E, respectively) because of their important ORAC (821 and 1054 mg of TE/g E), DPPH (586 and 750 mg of TE/g) and ABTS (1453 and 1319 mg of TE/g) results. Moreover, gallic acid, quercetin, quercetin galloyl glucoside, trigalloyl hexoside, procyanidin dimers and sulfated flavonoids were identified by LC-DAD-ESI-MS for the first time in this species. The relevant cytoprotective capacity (at 300 μg/mL) against β-amyloid peptide induced toxicity in PC12 cells of EtOAc fractions were corroborated with the chemical composition. In addition, purified molecules were tested for their ORAC and neuroprotective activity. Quercetin showed the best ORAC value (33.55 mmol TE/g polyphenols); nevertheless, procyanidin dimer exhibited an exceptionally efficient neuroprotective activity (100% of viability at 50 μg/mL). These findings suggest that this halophyte is a promising source of antioxidant and neuroprotective molecules for pharmaceutical purposes.

Comparative analyses of seeds of wild fruits of Rubus and Sambucus species from Southern Italy: fatty acid composition of the oil, total phenolic content, antioxidant and anti-inflammatory properties of the methanolic extracts.

PubMed

Fazio, Alessia; Plastina, Pierluigi; Meijerink, Jocelijn; Witkamp, Renger F; Gabriele, Bartolo

2013-10-15

Fruit seeds are byproducts from fruit processing. Characterisation of the bioactive compounds present in seeds and evaluation of their potential biological properties is therefore of particular importance in view of a possible valorisation of seeds as a source of health beneficial components. In this work, we have analysed the seeds of Sambucus and Rubus species in order to identify their bioactive components and to determine the antioxidant and anti-inflammatory activities of the extracts. We first analysed their oil content, in order to assess the fatty acid profile and tocopherol content. Moreover, the methanolic extracts of the seeds were analysed for their total phenolic contents and antioxidant capacities. Polyphenols were identified by HPLC-ESI-MS/MS analysis. Furthermore, extracts were evaluated for their inhibitory effects on the production of LPS-induced inflammatory mediators (NO, CCL-20) in RAW 264.7 cells. Our findings show that the methanolic extracts from Rubus seeds have strong antioxidant and anti-inflammatory properties and could therefore represent an attractive source of bioactive compounds for food, cosmetic, or pharmaceutical applications. Copyright © 2012 Elsevier Ltd. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Roach, Dennis Patrick; Rackow, Kirk A.

The FAA's Airworthiness Assurance NDI Validation Center, in conjunction with the Commercial Aircraft Composite Repair Committee, developed a set of composite reference standards to be used in NDT equipment calibration for accomplishment of damage assessment and post-repair inspection of all commercial aircraft composites. In this program, a series of NDI tests on a matrix of composite aircraft structures and prototype reference standards were completed in order to minimize the number of standards needed to carry out composite inspections on aircraft. Two tasks, related to composite laminates and non-metallic composite honeycomb configurations, were addressed. A suite of 64 honeycomb panels, representingmore » the bounding conditions of honeycomb construction on aircraft, was inspected using a wide array of NDI techniques. An analysis of the resulting data determined the variables that play a key role in setting up NDT equipment. This has resulted in a set of minimum honeycomb NDI reference standards that include these key variables. A sequence of subsequent tests determined that this minimum honeycomb reference standard set is able to fully support inspections over the full range of honeycomb construction scenarios found on commercial aircraft. In the solid composite laminate arena, G11 Phenolic was identified as a good generic solid laminate reference standard material. Testing determined matches in key velocity and acoustic impedance properties, as well as, low attenuation relative to carbon laminates. Furthermore, comparisons of resonance testing response curves from the G11 Phenolic NDI reference standard was very similar to the resonance response curves measured on the existing carbon and fiberglass laminates. NDI data shows that this material should work for both pulse-echo (velocity-based) and resonance (acoustic impedance-based) inspections.« less

Transglycosylation reactions, a main mechanism of phenolics incorporation in coffee melanoidins: Inhibition by Maillard reaction.

PubMed

Moreira, Ana S P; Nunes, Fernando M; Simões, Cristiana; Maciel, Elisabete; Domingues, Pedro; Domingues, M Rosário M; Coimbra, Manuel A

2017-07-15

Under roasting conditions, polysaccharides depolymerize and also are able to polymerize, forming new polymers through non-enzymatic transglycosylation reactions (TGRs). TGRs can also occur between carbohydrates and aglycones, such as the phenolic compounds present in daily consumed foods like coffee. In this study, glycosidically-linked phenolic compounds were quantified in coffee melanoidins, the polymeric nitrogenous brown-colored compounds formed during roasting, defined as end-products of Maillard reaction. One third of the phenolics present were in glycosidically-linked form. In addition, the roasting of solid-state mixtures mimicking coffee beans composition allowed the conclusion that proteins play a regulatory role in TGRs extension and, consequently, modulate melanoidins composition. Overall, the results obtained showed that TGRs are a main mechanism of phenolics incorporation in melanoidins and are inhibited by amino groups through Maillard reaction. Copyright © 2017 Elsevier Ltd. All rights reserved.

Antioxidant and antimicrobial properties of polyphenolic fractions from selected Moroccan red wines.

PubMed

Tenore, Gian Carlo; Basile, Adriana; Novellino, Ettore

2011-01-01

The present study is the first effort to a comprehensive evaluation of the antioxidant and antimicrobial activities of fractionated red wines from Morocco. The results obtained revealed that the wine samples were characterized by a higher phytochemical concentration than the same variety of wines with a different geographical origin and other more consumed red wines, confirming what was reported in a previous authors' work. The most phenolic-rich fractions were the ones containing phenolic acids and quercetin glucoronides from Syrah and Merlot wine samples while Cabernet Sauvignon exhibited the highest monomeric anthocyanin content. The antioxidant activity of wine extracts was tested by ferric reducing antioxidant power and 1,1-diphenyl-2-picrilhydrazyl assays. Samples revealed a higher reducing capacity than radical scavenging property and a good correlation between antioxidant activity and polyphenolic content values. As regards the antimicrobial properties, each fraction exhibited activity against a broad spectrum of food-borne microorganisms, revealing not only a moderate to high natural preserving capacity, but also potentially beneficial influence on human health. In consideration of the scarcity of data regarding composition and biological properties of Moroccan red wines, the present study may represent a valuable reference for wine consumers and producers. © 2011 Institute of Food Technologists®

Chemical composition and biological properties of Satureja avromanica Maroofi.

PubMed

Abdali, Elham; Javadi, Shima; Akhgari, Maryam; Hosseini, Seyran; Dastan, Dara

2017-03-01

Satureja avromanica is an indigenous plant which is frequently used as a spice in Avraman-Kurdistan region of Iran. The present study aimed to investigate the chemical composition, antimicrobial and antioxidant properties of the S. avromanica . In addition, rosmarinic acid and total phenolic content of S. avromanica was assessed by spectrophotometric method and HPTLC. The essential oil and methanolic extract were isolated by hydrodistillation and maceration methods, respectively. A total of 32 compounds representing 98.6% of the essential oil were identified by GC-MS and GC-FID. The main constituents were n -pentacosane (23.8%), spathulenol (11.5%), β-bourbonen (11.3%) and n -docosane (11.0%). The antibacterial activity of samples were carried out by disc diffusion method and evaluate the minimal inhibitory concentration (MIC) essential oil and methanolic extract were found to be effective against Staphylococcus aureus , Bacillus cereus and Bacillus pumilus . The highest scavenging activity was found for methanolic extract of S. avromanica (21.58 µg/mL) and the total phenolics of methanolic extract of S. avromanica was 95.3 mg GAE/g. The rosmarinic acid content of S. avromanica methanolic extract was 0.83 mg/g plant. Antioxidant activity and rosmarininc acid content of S. avromanica suggests that the essential oil and methanolic extract of S. avromanica has great potential for application as a natural antimicrobial and antioxidant agent to preserve food.

Studies on novel BiyXz-TiO2/SrTiO3 composites: Surface properties and visible light-driven photoactivity

NASA Astrophysics Data System (ADS)

Marchelek, Martyna; Grabowska, Ewelina; Klimczuk, Tomasz; Lisowski, Wojciech; Giamello, Elio; Zaleska-Medynska, Adriana

2018-03-01

A series of novel BiyXz-TiO2/SrTiO3 composites were prepared by multistep synthesis route. The as-prepared photocatalysts were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), diffuse reflectance spectroscopy (DRS), Fourier transform infrared (FT-IR), Raman spectra and BET analysis. The photocatalytic activity test was performed in aqueous solution of phenol under the irradiation of visible light range (λ ≥ 420 nm). Obtained results revealed that the BiOI_TiO2/SrTiO3 sample exhibit the highest photocatalytic activity under visible irradiation (0.6 μmol/dm3/min). Thus, it was demonstrated that modification of the TiO2/SrTiO3 microspheres by flowers-like structure made of bismuth oxyiodide resulted in enhancement of photocatalytic activity under visible light. The role of active species during the decomposition process of organic compound was investigated using different types of active species scavengers as well as electron paramagnetic resonance analysis (EPR). The study showed that in the BiOI_TiO2/SrTiO3/Vis system the holes (h+) plays relevant role in phenol decomposition. Furthermore, the stability and recyclable properties of obtained BiOI_TiO2/SrTiO3 sample were confirmed during three consecutive processes.

Phenolic compounds and fatty acid composition of organic and conventional grown pecan kernels

USDA-ARS?s Scientific Manuscript database

In this study, differences in contents of phenolic compounds and fatty acids in pecan kernels of organically versus conventionally grown pecan cultivars (‘Desirable’, ‘Cheyenne’, and ‘Wichita’) were evaluated. Although we were able to identify nine phenolic compounds (gallic acid, catechol, catechin...

Tribological study of non-asbestos fiber reinforced phenolic composites for braking applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gopal, P.; Dharani, L.R.; Blum, F.D.

A cashew modified phenolic resin was used as the binder to prepare several different nonasbestos fiber reinforced composite friction materials. Friction-wear tests were conducted at various loads, speeds and temperatures on a Chase friction testing machine. The fade and wear characteristics of glass and carbon fiber reinforced friction materials were studied. The wear rates of hybrid composites containing Kevlar{reg_sign} (registered trademark of E.I. duPont de Nemours) pulp were compared to those of control composites without Kevlar{reg_sign} pulp.

Fate and wetting potential of bio-refractory organics in membrane distillation for coke wastewater treatment.

PubMed

Ren, Jing; Li, Jianfeng; Chen, Zuliang; Cheng, Fangqin

2018-06-02

Membrane distillation (MD) has been hindered in industrial applications due to the potential wetting or fouling caused by complicated organic compositions. This study investigated the correlations between the fate and wetting potential of bio-refractory organics in the MD process, where three coke wastewater samples pre-treated with bio-degradation and coagulation served as feed solutions. Results showed that although most of the bio-refractory organics in coke wastewater were rejected by the hydrophobic membrane, some volatile aromatic organics including benzenes, phenols, quinolines and naphthalenes passed through the membrane during the MD process. Interestingly, membrane wetting occurred coincidently with the penetration of phenolic and heterocyclic organics. The wetting rate was obviously correlated with the feed composition and membrane surface properties. Ultimately, novel insights into the anti-wetting strategy of MD with bio-refractory organics was proposed, illustrating that the polyaluminum chloride/polyacrylamide coagulation not only removed contaminants which could accelerate membrane wetting, but also retarded membrane wetting by the complexation with organics. The deposition of these complexes on the membrane surface introduced a secondary hydrophilic layer on the hydrophobic substrate, which established a composite membrane structure with superior wetting resistance. These new findings would be beneficial to wetting control in membrane distillation for wastewater treatment. Copyright © 2018 Elsevier Ltd. All rights reserved.

Nutritional, antioxidative, and antimicrobial analysis of the Mediterranean hackberry (Celtis australis L.).

PubMed

Ota, Ajda; Višnjevec, Ana Miklavčič; Vidrih, Rajko; Prgomet, Željko; Nečemer, Marijan; Hribar, Janez; Cimerman, Nina Gunde; Možina, Sonja Smole; Bučar-Miklavčič, Milena; Ulrih, Nataša Poklar

2017-01-01

Celtis australis is a deciduous tree commonly known as Mediterranean hackberry or the European nettle tree. The fruit of hackberry are seldom used for nutritional purposes. The nutritional and physicochemical properties of ripe hackberry fruit from Istria (Marasi village near Vrsar, Croatia) were determined, including water, total fiber, protein, vitamin, mineral, and phenolic contents. This analysis demonstrates that the hackberry fruit is a valuable source of dietary fiber, protein, and vitamins, and of pigments such as lutein, β -carotene, zeaxanthin, and tocopherols. The seasonal differences associated with the different growth stages for the element composition, total phenolic content, and phenolic profile were also determined for hackberry mesocarp and leaves. Water and ethanol extracts were prepared from mesocarp and leaves harvested at different growth stages and their phenolic profiles and antioxidant and antimicrobial activities were investigated. This study demonstrates that water and ethanol extracts of hackberry fruit and leaves collected at different growth stages contain epicatechin, gallic acid, vanillic acid, 3,4-dihydroxybenzaldehyde, delphinidin-3,5-di-O-glucoside, cyanidin-3,5-di-O-glucoside, and pelargonidin-3,5-di-O-glucoside. They also show some antimicrobial and antifungal activities. Further studies are needed to identify and define the active ingredients of these hackberry leaf ethanol extracts.

Preparation of black soybean (Glycine max L) extract with enhanced levels of phenolic compound and estrogenic activity using high hydrostatic pressure and pre-germination

NASA Astrophysics Data System (ADS)

Kim, Min Young; Jang, Gwi Yeong; Lee, Sang Hoon; Kim, Kyung Mi; Lee, Junsoo; Jeong, Heon Sang

2018-04-01

We investigated the influence of high hydrostatic pressure (HHP) treatment on the estrogenic properties and conversion of the phenolic compounds in germinated black soybean. The black soybean was germinated for two- or four-days, and then subjected to HHP at 0.1, 50, 100, or 150 MPa for 12 or 24 h. The highest total polyphenol content (3.9 mg GAE/g), flavonoid content (0.8 mg CE/g), phenolic acid content (940 ± 18.96 μg/g), and isoflavonone content (2600 μg/g) were observed after germination for four days and HHP treatment at 100 MPa for 24 h. In terms of isoflavone composition, the malonyl, acetyl and β-glycoside contents decreased, while the aglycone content increased with HHP. The highest proliferative effect (150%) is observed at four days germination and HHP treatment at 100 MPa. These results suggest that application of HHP may provide useful information regarding the utility of black soybean as alternative hormone replacement therapy.

Effect of pectinase treatment on extraction of antioxidant phenols from pomace, for the production of puree-enriched cloudy apple juices.

PubMed

Oszmiański, Jan; Wojdyło, Aneta; Kolniak, Joanna

2011-07-15

Effects of pomace maceration on yield, turbidity, cloud stability, composition of phenolics, antioxidant activity and colour properties were studied, to evaluate the potential applicability of enzyme preparations in puree-enriched cloudy apple juice production. The yield of mixed juice and puree from pomace obtained in the enzymatic processing of apple ranged from 92.3% to 95.3%, significantly higher than the yield from the control without enzymatic pomace treatment (81.8%). Higher turbidity was obtained upon pomace treatment with Pectinex XXL and Pectinex Ultra SPL enzymes. The total content of phenolic compounds in apple pomace was higher than in raw juices (1520mg/kg and 441mg/L, respectively). The total polyphenol yields were higher in juices treated with Pectinex AFP L-4, Pectinex Yield Mash and Pectinex XXL, as compared to the control treatment. During 6months of storage, a significant change was observed in the content of polyphenols, especially in procyanidin fractions. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

Investigation of the usage of centrifuging waste of mineral wool melt (CMWW), contaminated with phenol and formaldehyde, in manufacturing of ceramic products.

PubMed

Kizinievič, Olga; Balkevičius, Valdas; Pranckevičienė, Jolanta; Kizinievič, Viktor

2014-08-01

Large amounts of centrifuging waste of mineral wool melt (CMWW) are created during the production of mineral wool. CMWW is technogenic aluminum silicate raw material, formed from the particles of undefibred melt (60-70%) and mineral wool fibers (30-40%). 0.3-0.6% of organic binder with phenol and formaldehyde in its composition exists in this material. Objective of the research is to investigate the possibility to use CMWW as an additive for the production of ceramic products, by neutralising phenol and formaldehyde existing in CMWW. Formation masses were prepared by incorporating 10%, 20% and 30% of CMWW additive and burned at various temperatures. It was identified that the amount of 10-30% of CMWW additive influences the following physical and mechanical properties of the ceramic body: lowers drying and firing shrinkage, density, increases compressive strength and water absorption. Investigations carried out show that CMWW waste can be used for the production of ceramic products of various purposes. Copyright © 2014 Elsevier Ltd. All rights reserved.

Steam reforming of simulated bio-oil on K-Ni-Cu-Mg-Ce-O/Al 2O 3: The effect of K

DOE PAGES

Yu, Ning; Rahman, Muhammad Mahfuzur; Chen, Jixiang; ...

2018-04-10

Steam reforming of simulated bio-oil (ethanol, acetone, phenol, and acetic acid) and phenol has been studied on K-Ni-Cu-Mg-Ce-O/Al 2O 3 composite catalysts. Complementary characterization techniques, such as nitrogen sorption, XRD, H 2-TPR, H 2-TPD, CO-TPD, CO-DRIFTS, and in situ XPS, were used to correlate surface structure and functionality to catalytic performance of potassium (K) doped catalysts. K doping of the Ni-Cu-Mg-Ce-O/Al 2O 3 catalyst created a Ni°/Ni 2+ mixed active phase, which not only enhanced steam reforming activity, but also suppressed the methanation reaction. In addition, K doping changed the surface acid-basic properties of the catalyst, which instead favor themore » gasifcation and water-gas shift reactions. In conclusion, with the combination of these effects, K doping of Ni-Cu-Mg-Ce-O/Al 2O 3 catalysts led to higher C1 yield and much lower methane formation, favoring hydrogen production in steam reforming of both phenol and simulated bio-oil.« less

Steam reforming of simulated bio-oil on K-Ni-Cu-Mg-Ce-O/Al 2O 3: The effect of K

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yu, Ning; Rahman, Muhammad Mahfuzur; Chen, Jixiang

Steam reforming of simulated bio-oil (ethanol, acetone, phenol, and acetic acid) and phenol has been studied on K-Ni-Cu-Mg-Ce-O/Al 2O 3 composite catalysts. Complementary characterization techniques, such as nitrogen sorption, XRD, H 2-TPR, H 2-TPD, CO-TPD, CO-DRIFTS, and in situ XPS, were used to correlate surface structure and functionality to catalytic performance of potassium (K) doped catalysts. K doping of the Ni-Cu-Mg-Ce-O/Al 2O 3 catalyst created a Ni°/Ni 2+ mixed active phase, which not only enhanced steam reforming activity, but also suppressed the methanation reaction. In addition, K doping changed the surface acid-basic properties of the catalyst, which instead favor themore » gasifcation and water-gas shift reactions. In conclusion, with the combination of these effects, K doping of Ni-Cu-Mg-Ce-O/Al 2O 3 catalysts led to higher C1 yield and much lower methane formation, favoring hydrogen production in steam reforming of both phenol and simulated bio-oil.« less

Removal of phenol from synthetic wastewater using carbon-mineral composite: Batch mechanisms and composition study

NASA Astrophysics Data System (ADS)

Kamaruddin, Mohamad Anuar; Alrozi, Rasyidah; Aziz, Hamidi Abdul; Han, Tan Yong; Yusoff, Mohd Suffian

2017-09-01

This study investigates the treatability of composite adsorbent made from waste materials and minerals which is widely available in Malaysia. The composite adsorbent was prepared based on wet attrition method which focuses on the determination of optimum dosage of each of raw materials amount by conventional design of experiment work. Zeolite, activated carbon, rice husk and limestone were ground to obtained particle size of 150 µm. 45.94% zeolite, 15.31% limestone, 4.38% activated carbon, 4.38% rice husk carbon and 30% of ordinary Portland cement (OPC). The mixture was mixed together under pre-determined mixing time. About 60% (by weight) of water was added and the mixture paste was allowed to harden for 24 hours and then submersed in water for three days for curing. Batch experimental study was performed on synthetic dissolving a known amount of solid crystal phenol with distilled water into the volumetric flasks. From the batch experimental study, it was revealed that the optimum shaking speed for removal of phenol was 200 rpm. The removal efficiency was 65%. The optimum shaking time for removing phenol was 60 minutes; the percentage achieved was 55%. The removal efficiency increased with the increased of the amount of composite adsorbent. The removal efficiency for optimum adsorbent dosage achieved 86%. Furthermore, the influence of pH solution was studied. The optimum pH for removing phenol was pH 6, with the removal percentage of 95%. The results implies that carbon-mineral based composite adsorbent is promising replacement for commercial adsorbent that provides alternative source for industrial adsorption application in various types of effluent treatment system.

In vitro antioxidant and in vivo photoprotective effect of pistachio (Pistacia vera L., variety Bronte) seed and skin extracts.

PubMed

Martorana, Maria; Arcoraci, Teresita; Rizza, Luisa; Cristani, Mariateresa; Bonina, Francesco Paolo; Saija, Antonina; Trombetta, Domenico; Tomaino, Antonio

2013-03-01

Pistachio (Pistacia vera L.) nuts are a rich source of phenolic compounds, known for their high antioxidant activity, and contained not only in the seeds but also in the skin. A pistachio cultivar of high quality is typical of Bronte, Sicily, Italy. The purpose of our study was to investigate the chemical composition and antioxidant properties of two polyphenol-rich extracts from skins (TP) and decorticated seeds (SP) of Bronte pistachios, and to verify the potential use of these extracts for topical photoprotective products. Chemical analysis showed that the TP and SP extracts contain high levels of phenolic compounds, but the TP extract is about ten times richer in phenols than the SP extract, being anthocyanins the most abundant compounds found in the TP extract. Both these extracts, and especially the TP extract, possess good radical scavenger/antioxidant properties, as shown in a series of in vitro assays carried out using homogenous and non-homogenous chemical environment. Furthermore both the TP extract and, although at a lower degree, the SP extract reduce, when topically applied, UV-B-induced skin erythema in human volunteers. These findings suggest that extracts from Bronte TP and SP could be successfully employed as photoprotective ingredients in topical cosmetic and pharmaceutical formulations. Copyright © 2013 Elsevier B.V. All rights reserved.

Phenolic and Aroma Composition of White Wines Produced by Prolonged Maceration and Maturation in Wooden Barrels

PubMed Central

Jedrejčić, Nikolina; Ganić, Karin Kovačević; Staver, Mario; Peršurić, Đordano

2015-01-01

Summary To investigate the phenolic and aroma composition of Malvazija istarska (Vitis vinifera L.) white wines produced by an unconventional technology comprising prolonged maceration followed by maturation in wooden barrels, representative samples were subjected to analysis by UV/Vis spectrometry, high-performance liquid chromatography, and gas chromatography-mass spectrometry. When compared to standard wines, the investigated samples contained higher levels of dry extract, volatile acidity, lactic acid, phenols, colour intensity, antioxidant activity, majority of monoterpenes, C13-norisoprenoids, methanol, higher alcohols, ethyl acetate, branched-chain esters and esters of hydroxy and dicarboxylic acids, ethylphenols, furans, and acetals, as well as lower levels of malic acid, β-damascenone, straight-chain fatty acids, ethyl and acetate esters. It was estimated that maceration had a stronger influence on phenols, and maturation on volatile aromas. Despite different vintages and technological details, the investigated wines showed a relative homogeneity in the composition, representing a clear and distinctive type. PMID:27904375

Optimisation of an oak chips-grape mix maceration process. Influence of chip dose and maceration time.

PubMed

Gordillo, Belén; Baca-Bocanegra, Berta; Rodriguez-Pulído, Francisco J; González-Miret, M Lourdes; García Estévez, Ignacio; Quijada-Morín, Natalia; Heredia, Francisco J; Escribano-Bailón, M Teresa

2016-09-01

Oak chips-related phenolics are able to modify the composition of red wine and modulate the colour stability. In this study, the effect of two maceration techniques, traditional and oak chips-grape mix process, on the phenolic composition and colour of Syrah red wines from warm climate was studied. Two doses of oak chips (3 and 6g/L) at two maceration times (5 and 10days) during fermentation was considered. Changes on phenolic composition (HPLC-DAD-MS), copigmentation/polymerisation (spectrophotometry), and colour (Tristimulus and Differential Colorimetry) were assessed by multivariate statistical techniques. The addition of oak chips at shorter maceration times enhanced phenolic extraction, colour and its stabilisation in comparison to the traditional maceration. On contrast, increasing chip dose in extended maceration time resulted in wines with lighter and less stable colour. Results open the possibility of optimise alternative technological applications to traditional grape maceration for avoiding the common loss of colour of wines from warm climate. Copyright © 2016 Elsevier Ltd. All rights reserved.

Salal (Gaultheria shallon) and aronia (Aronia melanocarpa) fruits from Orkney: Phenolic content, composition and effect of wine-making.

PubMed

McDougall, G J; Austin, C; Van Schayk, E; Martin, P

2016-08-15

The polyphenol content and composition of salal and aronia fruits from plants established in Orkney was examined. The composition of the salal fruits has not previously been recorded, and they contained anthocyanins, flavonols, hydroxycinnamates and proanthocyanins. The aronia fruits contained anthocyanins, hydroxycinnamates and flavonols as previously described. Although salal fruits had half the anthocyanin content of aronia fruits, salal wine had higher anthocyanin content, probably due to the relative stability of diglycoside pentose anthocyanins. The wines contained components suggestive of anthocyanin and flavonol degradation, but there was no consistent pattern to stability within phenolic sub-classes. Indeed, the wine made from equal amounts of salal and aronia fruits had patterns of recovery of individual phenolic components which could not be predicted from recoveries in wines from single fruits. This strongly suggests that stability of individual phenolic constituents during wine-making is influenced by the presence and relative stability of other components. Copyright © 2016 Elsevier Ltd. All rights reserved.

Fabrication of a Microbial Biosensor Based on QD-MWNT Supports by a One-Step Radiation Reaction and Detection of Phenolic Compounds in Red Wines

PubMed Central

Kim, Seul-Ki; Kwen, Hai-Doo; Choi, Seong-Ho

2011-01-01

An Acaligense sp.-immobilized biosensor was fabricated based on QD-MWNT composites as an electron transfer mediator and a microbe immobilization support by a one-step radiation reaction and used for sensing phenolic compounds in commercial red wines. First, a quantum dot-modified multi-wall carbon nanotube (QD-MWNT) composite was prepared in the presence of MWNT by a one-step radiation reaction in an aqueous solution at room temperature. The successful preparation of the QD-MWNT composite was confirmed by XPS, TEM, and elemental analysis. Second, the microbial biosensor was fabricated by immobilization of Acaligense sp. on the surface of the composite thin film of a glassy carbon (GC) electrode, which was prepared by a hand casting method with a mixture of the previously obtained composite and Nafion solution. The sensing ranges of the microbial biosensor based on CdS-MWNT and Cu2S-MWNT supports were 0.5–5.0 mM and 0.7–10 mM for phenol in a phosphate buffer solution, respectively. Total concentration of phenolic compounds contained in commercial red wines was also determined using the prepared microbial immobilized biosensor. PMID:22319395

Physio-Biochemical Composition and Untargeted Metabolomics of Cumin (Cuminum cyminum L.) Make It Promising Functional Food and Help in Mitigating Salinity Stress

PubMed Central

Pandey, Sonika; Patel, Manish Kumar; Mishra, Avinash; Jha, Bhavanath

2015-01-01

Cumin is an annual, aromatic, herbaceous, medicinal, spice plant, most widely used as a food additive and flavoring agent in different cuisines. The study is intended to comprehensively analyse physiological parameters, biochemical composition and metabolites under salinity stress. Seed germination index, rate of seed emergence, rate of seed germination, mean germination time, plant biomass, total chlorophyll and carotenoid contents decreased concomitantly with salinity. In contrast, total antioxidant activity, H2O2, proline and MDA contents increased concurrently with stress treatments. Total phenolic and flavonoid contents were decreased initially about 1.4-fold at 50 mM, and thereafter increased about 1.2-fold at 100 mM NaCl stress. Relative water content remained unchanged up to 50 mM NaCl stress, and thereafter decreased significantly. About 2.8-fold electrolyte leakage was found in 50 mM, which increases further 4-fold at 100 mM NaCl stress. Saturated fatty acids (FAs) increased gradually with salinity, whereas unsaturation index and degree of unsaturation change arbitrarily along with the percent quantity of unsaturated FAs. Total lipid and fatty acid composition were significantly influenced by salinity stress. A total of 45 differentially expressed metabolites were identified, including luteolin, salvianolic acid, kaempferol and quercetin, which are phenolic, flavonoid or alkaloids in nature and contain antioxidant activities. Additionally, metabolites with bioactivity such as anticancerous (docetaxel) and antimicrobial (megalomicin) properties were also identified. The study evidenced that plant shoots are a rich source of metabolites, essential amino acids, phenolic compounds and fatty acids, which unveil the medicinal potential of this plant, and also provide useful insight about metabolic responses under salinity stress. PMID:26641494

Physio-Biochemical Composition and Untargeted Metabolomics of Cumin (Cuminum cyminum L.) Make It Promising Functional Food and Help in Mitigating Salinity Stress.

PubMed

Pandey, Sonika; Patel, Manish Kumar; Mishra, Avinash; Jha, Bhavanath

2015-01-01

Cumin is an annual, aromatic, herbaceous, medicinal, spice plant, most widely used as a food additive and flavoring agent in different cuisines. The study is intended to comprehensively analyse physiological parameters, biochemical composition and metabolites under salinity stress. Seed germination index, rate of seed emergence, rate of seed germination, mean germination time, plant biomass, total chlorophyll and carotenoid contents decreased concomitantly with salinity. In contrast, total antioxidant activity, H2O2, proline and MDA contents increased concurrently with stress treatments. Total phenolic and flavonoid contents were decreased initially about 1.4-fold at 50 mM, and thereafter increased about 1.2-fold at 100 mM NaCl stress. Relative water content remained unchanged up to 50 mM NaCl stress, and thereafter decreased significantly. About 2.8-fold electrolyte leakage was found in 50 mM, which increases further 4-fold at 100 mM NaCl stress. Saturated fatty acids (FAs) increased gradually with salinity, whereas unsaturation index and degree of unsaturation change arbitrarily along with the percent quantity of unsaturated FAs. Total lipid and fatty acid composition were significantly influenced by salinity stress. A total of 45 differentially expressed metabolites were identified, including luteolin, salvianolic acid, kaempferol and quercetin, which are phenolic, flavonoid or alkaloids in nature and contain antioxidant activities. Additionally, metabolites with bioactivity such as anticancerous (docetaxel) and antimicrobial (megalomicin) properties were also identified. The study evidenced that plant shoots are a rich source of metabolites, essential amino acids, phenolic compounds and fatty acids, which unveil the medicinal potential of this plant, and also provide useful insight about metabolic responses under salinity stress.

Targeted and untargeted high resolution mass approach for a putative profiling of glycosylated simple phenols in hybrid grapes.

PubMed

Barnaba, Chiara; Dellacassa, Eduardo; Nicolini, Giorgio; Giacomelli, Mattia; Roman Villegas, Tomas; Nardin, Tiziana; Larcher, Roberto

2017-08-01

Vitis vinifera is one of the most widespread grapevines around the world representing the raw material for high quality wine production. The availability of more resistant interspecific hybrid vine varieties, developed from crosses between Vitis vinifera and other Vitis species, has generated much interest, also due to the low environmental effect of production. However, hybrid grape wine composition and varietal differences between interspecific hybrids have not been well defined, particularly for the simple phenols profile. The dynamic of these phenols in wines, where the glycosylated forms can be transformed into the free ones during winemaking, also raises an increasing health interest by their role as antoxidants in wine consumers. In this work an on-line SPE clean-up device, to reduce matrix interference, was combined with ultra-high liquid chromatography-high resolution mass spectrometry in order to increase understanding of the phenolic composition of hybrid grape varieties. Specifically, the phenolic composition of 4 hybrid grape varieties (red, Cabernet Cantor and Prior; white, Muscaris and Solaris) and 2 European grape varieties (red, Merlot; white, Chardonnay) was investigated, focusing on free and glycosidically bound simple phenols and considering compound distribution in pulp, skin, seeds and wine. Using a targeted approach 53 free simple phenols and 7 glycosidic precursors were quantified with quantification limits ranging from 0.001 to 2mgKg -1 and calibration R 2 of 0.99 for over 86% of compounds. The untargeted approach made it possible to tentatively identify 79 glycosylated precursors of selected free simple phenols in the form of -hexoside (N=30), -pentoside (21), -hexoside-hexoside (17), -hexoside-pentoside (4), -pentoside-hexoside (5) and -pentoside-pentoside (2) derivatives on the basis of accurate mass, isotopic pattern and MS/MS fragmentation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Controlled Fabrication of Functional Capsules Based on the Synergistic Interaction between Polyphenols and MOFs under Weak Basic Condition.

PubMed

Wang, Hui; Zhu, Wei; Ping, Yuan; Wang, Chen; Gao, Ning; Yin, Xianpeng; Gu, Chen; Ding, Dan; Brinker, C Jeffrey; Li, Guangtao

2017-04-26

Metal-organic coordination materials with controllable nanostructures are of widespread interest due to the coupled benefits of inorganic/organic building blocks and desired architectures. In this work, based on the finding of a synergistic interaction between metal-organic frameworks (MOFs) and natural polyphenols under weak basic condition, a facile strategy has been developed for directly fabricating diverse phenolic-inspired functional materials or metal-phenolic frameworks (MPFs) with controlled hollow nanostructures (polyhedral core-shell, rattle-like, hollow cage, etc.) and controllable size, morphology, and roughness, as well as composition. By further incorporating the diverse functionalities of polyphenols such as low toxicity and therapeutic properties, catalytic activity, and ability to serve as carbon precursors, into the novel assemblies, diverse artificially designed nanoarchitectures with target functionalities have been generated for an array of applications.

Curing property and plywood adhesive performance of resol-type phenol-urea-formaldehyde cocondensed resins

Treesearch

Masahiko Ohyama; Bunchiro Tomita; Chung-Yun Hse

1995-01-01

The curing processes and thermal properties of resol-type phenol-urea-formaldehyde cocondensed resins, which were prepared by alkaline treatments of the cocondensed resins once synthesized from UF-concentrate and phenol, were investigated by torsional braid analysis. The resol-type cocondensed resins displayed almost the same curing behaviors and heat-resistance as a...

Phenolic profiling of Portuguese propolis by LC-MS spectrometry: uncommon propolis rich in flavonoid glycosides.

PubMed

Falcão, Soraia I; Vale, Nuno; Gomes, Paula; Domingues, Maria R M; Freire, Cristina; Cardoso, Susana M; Vilas-Boas, Miguel

2013-01-01

Propolis is a chemically complex resinous substance collected by honeybees (Apis mellifera) from tree buds, comprising plant exudates, secreted substances from bee metabolism, pollen and waxes. Its chemical composition depends strongly on the plant sources available around the beehive, which have a direct impact in the quality and bioactivity of the propolis. Being as Portugal is a country of botanical diversity, the phenolic characterisation of propolis from the different regions is a priority. Extensive characterisation of the phenolic composition of Portuguese propolis from different continental regions and islands. Forty propolis ethanolic extracts were analysed extensively by liquid chromatography with diode-array detection coupled to electrospray ionisation tandem mass spectrometry (LC-DAD-ESI-MS(n) ). Seventy-six polyphenols were detected in the samples and two groups of propolis were established: the common temperate propolis, which contained the typical poplar phenolic compounds such as flavonoids and their methylated/esterified forms, phenylpropanoid acids and their esters, and an uncommon propolis type with an unusual composition in quercetin and kaempferol glycosides - some of them never described in propolis. The method allowed the establishment of the phenolic profile of Portuguese propolis from different geographical locations, and the possibility to use some phenolic compounds, such as kaempferol-dimethylether, as geographical markers. Data suggest that other botanical species in addition to poplar trees can be important sources of resins for Portuguese propolis. Copyright © 2012 John Wiley & Sons, Ltd.

An Oleuropein β-Glucosidase from Olive Fruit Is Involved in Determining the Phenolic Composition of Virgin Olive Oil

PubMed Central

Velázquez-Palmero, David; Romero-Segura, Carmen; García-Rodríguez, Rosa; Hernández, María L.; Vaistij, Fabián E.; Graham, Ian A.; Pérez, Ana G.; Martínez-Rivas, José M.

2017-01-01

Phenolic composition of virgin olive oil is determined by the enzymatic and/or chemical reactions that take place during olive fruit processing. Of these enzymes, β-glucosidase activity plays a relevant role in the transformation of the phenolic glycosides present in the olive fruit, generating different secoiridoid derivatives. The main goal of the present study was to characterize olive fruit β-glucosidase genes and enzymes responsible for the phenolic composition of virgin olive oil. To achieve that, we have isolated an olive β-glucosidase gene from cultivar Picual (OepGLU), expressed in Nicotiana benthamiana leaves and purified its corresponding recombinant enzyme. Western blot analysis showed that recombinant OepGLU protein is detected by an antibody raised against the purified native olive mesocarp β-glucosidase enzyme, and exhibits a deduced molecular mass of 65.0 kDa. The recombinant OepGLU enzyme showed activity on the major olive phenolic glycosides, with the highest levels with respect to oleuropein, followed by ligstroside and demethyloleuropein. In addition, expression analysis showed that olive GLU transcript level in olive fruit is spatially and temporally regulated in a cultivar-dependent manner. Furthermore, temperature, light and water regime regulate olive GLU gene expression in olive fruit mesocarp. All these data are consistent with the involvement of OepGLU enzyme in the formation of the major phenolic compounds present in virgin olive oil. PMID:29163620

The Role of Polyphenoloxidase, Peroxidase, and β-Glucosidase in Phenolics Accumulation in Olea europaea L. Fruits under Different Water Regimes

PubMed Central

Cirilli, Marco; Caruso, Giovanni; Gennai, Clizia; Urbani, Stefania; Frioni, Eleonora; Ruzzi, Maurizio; Servili, Maurizio; Gucci, Riccardo; Poerio, Elia; Muleo, Rosario

2017-01-01

Olive fruits and oils contain an array of compounds that contribute to their sensory and nutritional properties. Phenolic compounds in virgin oil and olive-derived products have been proven to be highly beneficial for human health, eliciting increasing attention from the food industry and consumers. Although phenolic compounds in olive fruit and oil have been extensively investigated, allowing the identification of the main classes of metabolites and their accumulation patterns, knowledge of the molecular and biochemical mechanisms regulating phenolic metabolism remains scarce. We focused on the role of polyphenoloxidase (PPO), peroxidase (PRX) and β-glucosidase (β-GLU) gene families and their enzyme activities in the accumulation of phenolic compounds during olive fruit development (35–146 days after full bloom), under either full irrigation (FI) or rain-fed (RF) conditions. The irrigation regime affected yield, maturation index, mesocarp oil content, fruit size, and pulp-to-pit ratio. Accumulation of fruit phenolics was higher in RF drupes than in FI ones. Members of each gene family were developmentally regulated, affected by water regime, and their transcript levels were correlated with the respective enzyme activities. During the early phase of drupe growth (35–43 days after full bloom), phenolic composition appeared to be linked to β-GLU and PRX activities, probably through their effects on oleuropein catabolism. Interestingly, a higher β-GLU activity was measured in immature RF drupes, as well as a higher content of the oleuropein derivate 3,4-DHPEA-EDA and verbascoside. Activity of PPO enzymes was slightly affected by the water status of trees during ripening (from 120 days after full bloom), but was not correlated with phenolics content. Overall, the main changes in phenolics content appeared soon after the supply of irrigation water and remained thereafter almost unchanged until maturity, despite fruit growth and the progressive decrease in pre-dawn leaf water potential. We suggest that enzymes involved in phenolic catabolism in the olive fruit have a differential sensitivity to soil water availability depending on fruit developmental stage. PMID:28536589

Composite electrochemical biosensors: a comparison of three different electrode matrices for the construction of amperometric tyrosinase biosensors.

PubMed

Serra, B; Jiménez, S; Mena, M L; Reviejo, A J; Pingarrón, J M

2002-03-01

A comparison of the behaviour of three different rigid composite matrices for the construction of amperometric tyrosinase biosensors, which are widely used for the detection of phenolic compounds, is reported. The composite electrode matrices were, graphite-Teflon; reticulated vitreous carbon (RVC)-epoxy resin; and graphite-ethylene/propylene/diene (EPD) terpolymer. After optimization of the experimental conditions, different aspects regarding the stability of the three composite tyrosinase electrode designs were considered and compared. A better reproducibility of the amperometric responses was found with the graphite-EPD electrodes, whereas a longer useful lifetime was observed for the graphite-Teflon electrodes. The kinetic parameters of the tyrosinase reaction were calculated for eight different phenolic compounds, as well as their corresponding calibration plots. The general trend in sensitivity was graphite-EPD>graphite-Teflon>RVC-epoxy resin. A correlation between sensitivity and the catalytic efficiency of the enzyme reaction for each phenolic substrate was found. Furthermore, differences in the sensitivity order for the phenolic compounds were observed among the three biocomposite electrodes, which suggests that the nature of the electrode matrix influences the interactions in the tyrosinase catalytic cycle.

Biological properties of propolis extracts: Something new from an ancient product.

PubMed

Zabaiou, Nada; Fouache, Allan; Trousson, Amalia; Baron, Silvère; Zellagui, Amar; Lahouel, Mesbah; Lobaccaro, Jean-Marc A

2017-10-01

Natural products are an interesting source of new therapeutics, especially for cancer therapy as 70% of them have botany origin. Propolis, a resinous mixture that honey bees collect and transform from tree buds, sap flows, or other botanical sources, has been used by ethnobotany and traditional practitioners as early in Egypt as 3000 BCE. Enriched in flavonoids, phenol acids and terpene derivatives, propolis has been widely used for its antibacterial, antifungal and anti-inflammatory properties. Even though it is a challenge to standardize propolis composition, chemical analyses have pointed out interesting molecules that also present anti-oxidant and anti-proliferative properties that are of interest in the field of anti-cancer therapy. This review describes the various geographical origins and compositions of propolis, and analyzes how the main compounds of propolis could modulate cell signaling. A focus is made on the putative use of propolis in prostate cancer. Copyright © 2017 Elsevier B.V. All rights reserved.

Exploration of avocado by-products as natural sources of bioactive compounds.

PubMed

Tremocoldi, Maria Augusta; Rosalen, Pedro Luiz; Franchin, Marcelo; Massarioli, Adna Prado; Denny, Carina; Daiuto, Érica Regina; Paschoal, Jonas Augusto Rizzato; Melo, Priscilla Siqueira; Alencar, Severino Matias de

2018-01-01

This study aimed to evaluate the antioxidant, anti-inflammatory, and cytotoxic properties and phenolic composition of peel and seed of avocado varieties Hass and Fuerte using green solvents. Ethanol soluble compounds were identified in peel and seed of both varieties using HPLC-MS/MS and quantified using HPLC-DAD. Agro-industrial by-products of both varieties exhibited high radical scavenging activity against synthetic free radicals (DPPH and ABTS) and reactive oxygen species (peroxyl, superoxide, and hypochlorous acid) and high ability to reduce Fe3+ to Fe2+. The main compounds with significant contribution to the antioxidant activity determined by online HPLC-ABTS●+ analyses were procyanidin B2 and epicatechin in the peel and trans-5-O-caffeoyl-D-quinic acid, procyanidin B1, catechin, and epicatechin in the seed. Peel of Fuerte significantly suppressed TNF-α and nitric oxide (NO) release (459.3 pg/mL and 8.5 μM, respectively), possibly because of the high phenolic content and antioxidant activity detected. Avocado agro-industrial by-products can be used for food and pharmaceutical purposes due to their antioxidant and anti-inflammatory properties.

Exploration of avocado by-products as natural sources of bioactive compounds

PubMed Central

Tremocoldi, Maria Augusta; Rosalen, Pedro Luiz; Franchin, Marcelo; Massarioli, Adna Prado; Denny, Carina; Daiuto, Érica Regina; Paschoal, Jonas Augusto Rizzato; Melo, Priscilla Siqueira

2018-01-01

This study aimed to evaluate the antioxidant, anti-inflammatory, and cytotoxic properties and phenolic composition of peel and seed of avocado varieties Hass and Fuerte using green solvents. Ethanol soluble compounds were identified in peel and seed of both varieties using HPLC-MS/MS and quantified using HPLC-DAD. Agro-industrial by-products of both varieties exhibited high radical scavenging activity against synthetic free radicals (DPPH and ABTS) and reactive oxygen species (peroxyl, superoxide, and hypochlorous acid) and high ability to reduce Fe3+ to Fe2+. The main compounds with significant contribution to the antioxidant activity determined by online HPLC-ABTS●+ analyses were procyanidin B2 and epicatechin in the peel and trans-5-O-caffeoyl-D-quinic acid, procyanidin B1, catechin, and epicatechin in the seed. Peel of Fuerte significantly suppressed TNF-α and nitric oxide (NO) release (459.3 pg/mL and 8.5 μM, respectively), possibly because of the high phenolic content and antioxidant activity detected. Avocado agro-industrial by-products can be used for food and pharmaceutical purposes due to their antioxidant and anti-inflammatory properties. PMID:29444125

Phytochemical composition and in vitro functional properties of three wild rose hips and their traditional preserves.

PubMed

Nađpal, Jelena D; Lesjak, Marija M; Mrkonjić, Zorica O; Majkić, Tatjana M; Četojević-Simin, Dragana D; Mimica-Dukić, Neda M; Beara, Ivana N

2018-02-15

The aim of the present study was investigation of the phenolic profile, ascorbic acid content, antioxidant, anti-acetylcholinesterase, anti-inflammatory and cytotoxic activity of rose hips and the preserves (purée and jam) of three insufficiently examined Rosa species: Rosa dumalis Bechst., R. dumetorum Thuill. and R. sempervirens L. The liquid chromatography-tandem mass spectrometry analysis resulted in quantification of 14 of the 45 phenolic compounds examined, with ellagic acid as the most dominant. Notable antioxidant activity of all three species was confirmed through several assays. Moderate inhibition of acetylcholinesterase by extracts of all investigated Rosa species was observed. Several extracts of examined Rosa species demonstrated inhibition potency towards production of some monitored eicosanoids in cyclooxygenase-1 and 12-lipoxygenase pathways. Two R. sempervirens extracts exerted cytotoxic activity against HeLa and HT-29 cell lines, but were inactive towards MRC-5 and MCF7. The results support the potential of these rose hips as food with health-promoting properties. Copyright © 2017 Elsevier Ltd. All rights reserved.

Influence of added bean flour (Phaseolus vulgaris L.) on some physical and nutritional properties of wheat flour tortillas.

PubMed

Anton, Alex A; Ross, Kelly A; Lukow, Odean M; Fulcher, R Gary; Arntfield, Susan D

2008-07-01

Composite flours containing 15%, 25%, or 35% of small red, black, pinto, or navy bean flours (BF) and wheat were made into tortillas. Dough rheology, firmness, cohesiveness, rollability, and some physical properties of tortillas were negatively affected as BF concentration increased regardless of bean cultivar. Nutritionally, all bean tortillas had significantly higher levels of crude protein, total phenols, 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS(+)) in vitro antioxidant activity (AA) and antinutritional compounds such as phytic acid (PA) and trypsin inhibitors (TI) than the wheat control. Tortillas to which 35% of small red, pinto and black BF was added had the highest levels of phenols, which were significantly correlated with both DPPH (r=0.99) and ABTS(+) (r=0.99) AA. Compared to raw flours, PA and TI were reduced from 37.37% to 43.78% and from 50% to 66%, respectively, in the tortillas. Overall analysis indicated that tortillas with acceptable texture and improved nutritional profile were produced at 25% substitution. Copyright © 2007 Elsevier Ltd. All rights reserved.

Statistical interpretation of chromatic indicators in correlation to phytochemical profile of a sulfur dioxide-free mulberry (Morus nigra) wine submitted to non-thermal maturation processes.

PubMed

Tchabo, William; Ma, Yongkun; Kwaw, Emmanuel; Zhang, Haining; Xiao, Lulu; Apaliya, Maurice T

2018-01-15

The four different methods of color measurement of wine proposed by Boulton, Giusti, Glories and Commission International de l'Eclairage (CIE) were applied to assess the statistical relationship between the phytochemical profile and chromatic characteristics of sulfur dioxide-free mulberry (Morus nigra) wine submitted to non-thermal maturation processes. The alteration in chromatic properties and phenolic composition of non-thermal aged mulberry wine were examined, aided by the used of Pearson correlation, cluster and principal component analysis. The results revealed a positive effect of non-thermal processes on phytochemical families of wines. From Pearson correlation analysis relationships between chromatic indexes and flavonols as well as anthocyanins were established. Cluster analysis highlighted similarities between Boulton and Giusti parameters, as well as Glories and CIE parameters in the assessment of chromatic properties of wines. Finally, principal component analysis was able to discriminate wines subjected to different maturation techniques on the basis of their chromatic and phenolics characteristics. Copyright © 2017. Published by Elsevier Ltd.

A Member of Complementary Medicinal Food: Anatolian Royal Jellies, Their Chemical Compositions, and Antioxidant Properties.

PubMed

Kolayli, Sevgi; Sahin, Huseyin; Can, Zehra; Yildiz, Oktay; Malkoc, Meltem; Asadov, Alsever

2016-10-01

This study investigated various chemical and antioxidant properties of Anatolian royal jelly samples. Moisture, pH, total protein, 10-hydroxy-2-decenoic acid (10-HDA) and sugars were analyzed from 18 samples. Total phenolic contents, ferric reducing antioxidant capacity and 2,2-diphenyl-1-picryhydrazyl (DPPH) free radical scavenging activity were measured as antioxidant determinants. 10-HDA contents and total protein content of fresh weight ranged between 1.0% and 3.9%, and 11.4% and 15.8%, respectively. The main sugars detected were glucose and fructose. Maltose, trehalose, and melibiose were detected at less than 1.0% in all samples. Lactose, a milk sugar, was detected in only 3 samples, at values between 0.8% and 1.4%. Total henolic content ranged from 91.0 to 301.0 mg gallic acid equivalents/kg fresh weight. Antioxidant activity is due to both to the total phenolic content, proteins and fatty acids of royal jelly. Anatolian royal jelly samples were not different from other royal jelly samples from across the world. © The Author(s) 2015.

Process for preparing a liquid fuel composition

DOEpatents

Singerman, Gary M.

1982-03-16

A process for preparing a liquid fuel composition which comprises liquefying coal, separating a mixture of phenols from said liquefied coal, converting said phenols to the corresponding mixture of anisoles, subjecting at least a portion of the remainder of said liquefied coal to hydrotreatment, subjecting at least a portion of said hydrotreated liquefied coal to reforming to obtain reformate and then combining at least a portion of said anisoles and at least a portion of said reformate to obtain said liquid fuel composition.

Foamable compositions and formations treatment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Clampitt, R.L.

1981-11-17

Thermally stable foamable gelled compositions are disclosed suitable for postprimary oil recovery e.g., steam- or gas-foamed systems comprising water, a surfactant, a polymeric viscosifier, an aldehyde component, and at least one phenolic component such as resorcinol, catechol, and the like, as well as selected oxidized phenolic materials such as 1,4-benzoquinone of natural or synthetic origin and natural and modified tannins. The gel compositions can additionally contain gel stabilizers such as sulfomethylated quebracho (Smq) and chemical buffering agents such as sodium bicarbonate.

Chemical composition and antioxidant activity of phenolic compounds and essential oils from Calamintha nepeta L.

PubMed

Khodja, Nabyla Khaled; Boulekbache, Lila; Chegdani, Fatima; Dahmani, Karima; Bennis, Faiza; Madani, Khodir

2018-05-24

Background Essential oils, infusion and decoction extracts of Calamintha nepeta L. were evaluated for their bioactive substances (polyphenols and essential oils) and antioxidant activities. Methods The amounts of phenolic compounds were determined by colorimetric assays and identified by high performance and liquid chromatography coupled with ultraviolet detector (HPLC-UV) method. The chemical composition of essential oils was determined by gas-chromatography coupled with mass spectrometry (GC/MS) method. For the evaluation of the antioxidant activity of essential oils and extracts, two different assays (reducing power and DPPH radical scavenging activity) were used. Results Infusion extract presented the highest phenolic content, followed by the decoction one, while the lowest amount was observed in essential oils. The amount of flavonoids of the decocted extract was higher than that of the infused one. The phenolic profile of C. nepeta infusion and decoction extracts revealed the presence of 28 and 13 peaks, respectively. Four phenolics compounds were identified in infusion (gallic acid (GA), rosmarinic acid (RA), caffeine (C) and caffeic acid (CA)) and two were identified in decoction (GA and RA). The chemical composition of essential oils revealed the presence of 29 compounds, accounting for the 99.7% of the total oils. Major compounds of essential oil (EO) were trans-menthone (50.06%) and pulegone (33.46%). Infusion and decoction extracts revealed an interesting antioxidant activity which correlates positively with their total phenolic contents. Conclusions These results showed that Calamintha nepeta could be considered as a valuable source of phenolics and essential oils with potent antioxidant activity.

Wines in contact with oak wood: the impact of the variety (Carménère and Cabernet Sauvignon), format (barrels, chips and staves) and aging time on the phenolic composition.

PubMed

Laqui-Estaña, Jaime; López-Solís, Remigio; Peña-Neira, Álvaro; Medel-Marabolí, Marcela; Obreque-Slier, Elías

2018-06-13

This study characterized the flavonoid and non-flavonoid phenolic composition of Carménère and Cabernet Sauvignon wines that were in contact with barrels, chips and staves during a 12-month aging period. The wines were evaluated by spectrophotometric (for total phenols, anthocyanins and tannins, colorant intensity, hue, CIElab parameters and fractionation into mono-, oligo- and polymer of proanthocyanidins) and HPLC-DAD analyses (for ellagitannins, gallotannins, anthocyanins and low molecular weight phenols). Wines in contact with oak wood presented a strong enrichment with non-flavonoid compounds, such as caffeic, gallic, ellagic acids and ellagitannins. Wines in contact with staves stood out for the increased presence of total phenols, vanillic acid and higher color intensity, while wines aged in contact with chips showed large contents of proanthocyanidin gallates. Wines aged in barrels exhibited high contents of ellagitannins and ethyl gallates. The effect of wood on the phenolic composition was mostly associated to the original and intrinsic characteristics of each grape variety. Extraction of phenolic compounds from oak wood during wine aging is closely related to the wood format, grape variety (Carménère or Cabernet Sauvignon) and aging time. The final effect of wood on wine would be related not just to the transference of polyphenols from wood but also to structural modifications of grape polyphenols. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Volatile compounds and phenolic composition of virgin olive oil: optimization of temperature and time of exposure of olive pastes to air contact during the mechanical extraction process.

PubMed

Servili, Maurizio; Selvaggini, Roberto; Taticchi, Agnese; Esposto, Sonia; Montedoro, GianFrancesco

2003-12-31

The operative conditions of malaxation such as temperature and time of exposure of olive pastes to air contact (TEOPAC) affect volatile and phenolic composition of virgin olive oil (VOO) and, as a consequence, its sensory and healthy qualities. In this paper, optimal temperature and TEOPAC during malaxation were studied, in lab scale, in two Italian cultivars using phenolic compounds, volatile composition, and sensory analysis of VOO as markers. The optimal temperature and TEOPAC, selected by response surface modeling,were cultivar-dependent being 30 min of TEOPAC at the lowest temperature investigated (22 degrees C) and 0 min of TEOPAC at 26 degrees C for Frantoio and Moraiolo cultivars, respectively.

Chemical characterization of some aqueous leachates from crop residues in 'CELSS'

NASA Technical Reports Server (NTRS)

Madsen, Brooks C.

1992-01-01

Aqueous leachate samples prepared from crop residues that are produced as a component of the Controlled Ecological Life Support System program designed to support long duration space missions have been compared and general chemical characterization has been accomplished. Solid phase extraction and high performance liquid chromatography were used to accomplish comparisons based on chromatographic and ultraviolet absorption properties of the components that are present. Specific compounds were not identified, however, general composition related to the presence of phenol-like compounds was explored.

Assessment of the polyphenolic composition of the organic extracts of Mauritian black teas: a potential contributor to their antioxidant functions.

PubMed

Luximon-Ramma, Amitabye; Neergheen, Vidushi S; Bahorun, Theeshan; Crozier, Alan; Zbarsky, Virginia; Datla, Krishna P; Dexter, David T; Aruoma, Okezie I

2006-01-01

There is increasing interest in the emerging view that tea improves the antioxidant status in vivo and thereby helps to lower risk of certain types of cancer, coronary heart disease and stroke and its component biofactors could provide prophylactic potential for these diseases. The polyphenolic composition and the antioxidant properties of organic extracts (acetone/methanol) of Mauritian commercial black teas were evaluated. HPLC data of the individual compounds revealed remarkably high levels (+)-Catechin ((+)-C), (-)-epicatechin ((-)-EC), (-)-epicatechin 3-gallate ((-)-ECG), (-)-epigallocatechin ((-)-EGC), (-)-epigallocatechin 3-gallate ((-)-EGCG) and gallic acid. Analysis of hydrolysed extracts indicated that quercetin was the dominant flavonol aglycone with traces of myricetin and kaempferol. Based on the Ferric Reducing Antioxidant Power (FRAP) and the Trolox Equivalent Antioxidant Capacity (TEAC) assays Extra tea from Bois Chéri exhibited the highest antioxidant potential. Linear regression analyses showed that the antioxidant capacities of the organic extracts are strongly influenced by total phenols (TEAC: r=0.95 and FRAP: r=0.96) and to a lesser extent by total proanthocyanidin and total flavonoid contents. Catechins and gallic acid seem to add up to the overall antioxidant capacity of black tea extracts. The fresh tea leaves had high levels of total phenols, total flavonoids, total proanthocyanidin and exhibited greater antioxidant potential when compared with black teas. Organic extracts of endemic teas represent useful source of phenolic antioxidants supplements for prophylactic use.

Pilot-plant evaluation of TiO2 and TiO2-based hybrid photocatalysts for solar treatment of polluted water.

PubMed

Andronic, Luminita; Isac, Luminita; Miralles-Cuevas, Sara; Visa, Maria; Oller, Isabel; Duta, Anca; Malato, Sixto

2016-12-15

Materials with photocatalytic and adsorption properties for advanced wastewater treatment targeting reuse were studied. Making use of TiO 2 as a well-known photocatalyst, Cu 2 S as a Vis-active semiconductor, and fly ash as a good adsorbent, dispersed mixtures/composites were prepared to remove pollutants from wastewater. X-ray diffraction, scanning electron microscopy, energy-dispersive X-Ray spectroscopy, atomic force microscopy, band gap energy, point of zero charge (pH pzc ) and BET porosity were used to characterize the substrates. Phenol, imidacloprid and dichloroacetic acid were used as pollutants for photocatalytic activity of the new photocatalysts. Experiments using the new dispersed powders were carried out at laboratory scale in two solar simulators and under natural solar irradiation at the Plataforma Solar de Almería, in a Compound Parabolic Collector (CPC) for a comparative analysis of pollutants removal and mineralization efficiencies, and to identify features that could facilitate photocatalyst separation and reuse. The results show that radiation intensity significantly affects the phenol degradation rate. The composite mixture of TiO 2 and fly ash is 2-3 times less active than sol-gel TiO 2 . Photodegradation kinetic data on the highly active TiO 2 are compared for pollutants elimination. Photodegradation of dichloroacetic acid was fast and complete after 90min in the CPC, while after 150min imidacloprid and phenol removal was 90% and 56% respectively. Copyright © 2016 Elsevier B.V. All rights reserved.

Tailoring the properties of a zero-valent iron-based composite by mechanochemistry for nitrophenols degradation in wastewaters.

PubMed

Cagnetta, Giovanni; Huang, Jun; Lomovskiy, Igor O; Yu, Gang

2017-11-01

Zero-valent iron (ZVI) is a valuable material for environmental remediation, because of its safeness, large availability, and inexpensiveness. Moreover, its reactivity can be improved by addition of (nano-) particles of other elements such as noble metals. However, common preparation methods for this kind of iron-based composites involve wet precipitation of noble metal salt precursors, so they are often expensive and not green. Mechanochemical procedures can provide a solvent-free alternative, even at a large scale. The present study demonstrates that it is possible to tailor functional properties of ZVI-based materials, utilizing high-energy ball milling. All main preparation parameters are investigated and discussed. Specifically, a copper-carbon-iron ternary composite was prepared for fast degradation of 4-nitrophenol (utilized as model pollutant) to 4-aminophenol and other phenolic compounds. Copper and carbon are purposely chosen to insert specific properties to the composite: Copper acts as efficient nano-cathode that enhances electron transfer from iron to 4-nitrophenol, while carbon protects the iron surface from fast oxidation in open air. In this way, the reactive material can rapidly reduce high concentration of nitrophenols in water, it does not require acid washing to be activated, and can be stored in open air for one week without any significant activity loss.

Composite materials for precision space reflector panels

NASA Technical Reports Server (NTRS)

Tompkins, Stephen S.; Funk, Joan G.; Bowles, David E.; Towell, Timothy W.; Connell, John W.

1992-01-01

One of the critical technology needs of large precision reflectors for future astrophysical and optical communications satellites lies in the area of structural materials. Results from a materials research and development program at NASA Langley Research Center to provide materials for these reflector applications are discussed. Advanced materials that meet the reflector panel requirements are identified, and thermal, mechanical and durability properties of candidate materials after exposure to simulated space environments are compared. A parabolic, graphite-phenolic honeycomb composite panel having a surface accuracy of 70.8 microinches rms and an areal weight of 1.17 lbm/sq ft was fabricated with T50/ERL1962 facesheets, a PAEI thermoplastic surface film, and Al and SiO(x) coatings.

Synthesis, characterization, bioactivity and potential application of phenolic acid grafted chitosan: A review.

PubMed

Liu, Jun; Pu, Huimin; Liu, Shuang; Kan, Juan; Jin, Changhai

2017-10-15

In recent years, increasing attention has been paid to the grafting of phenolic acid onto chitosan in order to enhance the bioactivity and widen the application of chitosan. Here, we present a comprehensive overview on the recent advances of phenolic acid grafted chitosan (phenolic acid-g-chitosan) in many aspects, including the synthetic method, structural characterization, biological activity, physicochemical property and potential application. In general, four kinds of techniques including carbodiimide based coupling, enzyme catalyzed grafting, free radical mediated grafting and electrochemical methods are frequently used for the synthesis of phenolic acid-g-chitosan. The structural characterization of phenolic acid-g-chitosan can be determined by several instrumental methods. The physicochemical properties of chitosan are greatly altered after grafting. As compared with chitosan, phenolic acid-g-chitosan exhibits enhanced antioxidant, antimicrobial, antitumor, anti-allergic, anti-inflammatory, anti-diabetic and acetylcholinesterase inhibitory activities. Notably, phenolic acid-g-chitosan shows potential applications in many fields as coating agent, packing material, encapsulation agent and bioadsorbent. Copyright © 2017 Elsevier Ltd. All rights reserved.

Yeast effects on Pinot noir wine phenolics, color, and tannin composition.

PubMed

Carew, Anna L; Smith, Paul; Close, Dugald C; Curtin, Chris; Dambergs, Robert G

2013-10-16

Extraction and stabilization of wine phenolics can be challenging for wine makers. This study examined how yeast choice affected phenolic outcomes in Pinot noir wine. Five yeast treatments were applied in replicated microvinification, and wines were analyzed by UV-visible spectrophotometry. At bottling, yeast treatment Saccharomyces cerevisiae RC212 wine had significantly higher concentrations of total pigment, free anthocyanin, nonbleachable pigment, and total tannin and showed high color density. Some phenolic effects were retained at 6 months' bottle age, and RC212 and S. cerevisae EC1118 wines showed increased mean nonbleachable pigment concentrations. Wine tannin composition analysis showed three treatments were associated with a higher percentage of trihydroxylated subunits (skin tannin indicator). A high degree of tannin polymerization was observed in wines made with RC212 and Torulaspora delbruekii , whereas tannin size by gel permeation chromatography was higher only in the RC212 wines. The results emphasize the importance of yeast strain choice for optimizing Pinot noir wine phenolics.

[The changes in contents and composition of phenolic acids during cell xylem growth in scots pine].

PubMed

Antonova, G F; Zheliznichenko, T V; Stasova, V V

2011-01-01

The contents and composition of alcohol soluble phenolic acids were studied during cell xylem growth in the course of wood annual increment formation in the stems of Scots pine. The cells of cambium zone, of two stages of expansion growth and the outset of secondary thickening zone (before lignification) were successively gathered from the stem segments of 25-old pine trees in the period of earlywood xylem formation with constant anatomical and histochemical control. The contents of free and bound forms of phenolic acids, isolated by 80% ethanol from tissues, as well as of their ethers and esters were calculated both per dry weight and per cell. The content and relation of the fractions and the composition of phenolic acid have been found to change significantly from cambium zone to the outset of tracheid secondary thickening. The character of the variations depends on a calculation method. According to the calculation per cell the amount of free and bound phenolic acids and in their composition of esters and especially ethers increased at the first step of expansion growth zone, decreased at the second one and rose again in the outset of secondary wall deposition. In dependence on the stage of cell development the pool of bound phenolic acids exceeded of free acid pool in 2-5 times. Sinapic and ferulic acids dominated in the composition of free hydroxycinnamic acids. The content and composition of hydroxycinnamic acids in ethers and esters depended on cell development phase. In cambium p-coumaric and sinapic acids were principal aglycons in ethers, at other stages these were sinapic and caffeic acids. The esters in cambium zone included essentially p-coumaric acid and at the other stages - sinapic and ferulic acids. At the first phase of growth benzoic acid was connected principally by ester bonds. The pool of these esters decreased from the first phase of growth to the outset of cell wall thickening and in proportion to this the level of free benzoic acid rose.

Tooling Foam for Structural Composite Applications

NASA Technical Reports Server (NTRS)

DeLay, Tom; Smith, Brett H.; Ely, Kevin; MacArthur, Doug

1998-01-01

Tooling technology applications for composite structures fabrication have been expanded at MSFC's Productivity Enhancement Complex (PEC). Engineers from NASA/MSFC and Lockheed Martin Corporation have developed a tooling foam for use in composite materials processing and manufacturing that exhibits superior thermal and mechanical properties in comparison with other tooling foam materials. This tooling foam is also compatible with most preimpregnated composite resins such as epoxy, bismaleimide, phenolic and their associated cure cycles. MARCORE tooling foam has excellent processability for applications requiring either integral or removable tooling. It can also be tailored to meet the requirements for composite processing of parts with unlimited cross sectional area. A shelf life of at least six months is easily maintained when components are stored between 50F - 70F. The MARCORE tooling foam system is a two component urethane-modified polyisocyanurate, high density rigid foam with zero ozone depletion potential. This readily machineable, lightweight tooling foam is ideal for composite structures fabrication and is dimensionally stable at temperatures up to 350F and pressures of 100 psi.

Changes in the phenolic composition of pancake fractions made from refined and whole-wheat flour of two wheat varieties

USDA-ARS?s Scientific Manuscript database

In this study, we investigated the changes in the levels of phenolic acids during pancake preparation from refined and whole-wheat flours of two wheat varieties. Comparison of the efficacy of two commonly used methods for hydrolysis and extraction of phenolic acids, namely ultrasonic-assisted extrac...

Soybean seed phenol, lignin, and isoflavones and sugars composition are altered by Foliar Boron application in soybean under water stress

USDA-ARS?s Scientific Manuscript database

Previous research showed that foliar boron (B) fertilizer at flowering or seed-fill growth stages altered seed protein, oil, and fatty acids. The objective of this research was to investigate the effects of foliar B fertilizer on seed phenolics (phenol, lignin, and isoflavones) and sugars concentrat...

Phenolic Profiles and Antioxidant Activity of Lotus Root Varieties.

PubMed

Yi, Yang; Sun, Jie; Xie, Jun; Min, Ting; Wang, Li-Mei; Wang, Hong-Xun

2016-06-30

Lotus root attracts increasing attention mainly because of its phenolic compounds known as natural antioxidants. Its thirteen varieties were systematically analyzed on the content, distribution, composition and antioxidant activity of phenolic compounds for a better understanding of this aquatic vegetable. The respective mean contents of total phenolics in their flesh, peel and nodes were 1.81, 4.30 and 7.35 mg gallic acid equivalents (GAE)/g fresh weight (FW), and those of total flavonoids were 3.35, 7.69 and 15.58 mg rutin equivalents/g FW. The phenolic composition determined by a high-performance liquid chromatography method varied significantly among varieties and parts. The phenolics of flesh were mainly composed of gallocatechin and catechin; those of peel and node were mainly composed of gallocatechin, gallic acid, catechin and epicatechin. The antioxidant activities of phenolic extracts in increasing order were flesh, peel and node; their mean concentrations for 50% inhibition of 2,2-diphenyl-1-picrylhydrazyl radical were 46.00, 26.43 and 21.72 µg GAE/mL, and their mean values representing ferric reducing antioxidant power were 75.91, 87.66 and 100.43 µg Trolox equivalents/100 µg GAE, respectively. "Zoumayang", "Baheou", "No. 5 elian" and "Guixi Fuou" were the hierarchically clustered varieties with relatively higher phenolic content and stronger antioxidant activity as compared with the others. Especially, their nodes and peels are promising sources of antioxidants for human nutrition.

Antioxidant activity, phenolic-flavonoid content and high-performance liquid chromatography profiling of three different variants of Syzygium cumini seeds: A comparative study.

PubMed

Priya, Syama Hari; Prakasan, Nisha; Purushothaman, Jayamurthy

2017-01-01

The medicinally important phytochemicals present in Syzygium cumini seeds probably accounts for its wide use in traditional systems of medicines in India, like Ayurveda, Unani, and Siddha. The aim of the study was to determine the antioxidant potential of three different geographical variants of S. cumini seeds and to compare the phenolic profiling to know the effect of geographical variation in phenolic composition. Total phenolic and flavonoid content of S. cumini seeds were analyzed. Antioxidant activities in terms of 2,2-diphenyl-1-picrylhydrazyl, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid), nitric oxide and superoxide radical scavenging assays were performed. The most active fractions were subjected to high-performance liquid chromatography (HPLC) profiling to identify the phenolic composition. Among all the fractions, 70% methanol fraction of S. cumini seed showed significant antioxidant potential. There existed a linear correlation between phenolic content and antioxidant activity. HPLC profiling of 70% methanol (ME) fractions of all the variants revealed the presence of phenolic compounds with high concentrations of ellagic acid and gallic acid. The differences in phenolic concentration due to geographical changes might be the reason for higher antioxidant potential showed by 70% ME of Trivandrum variant. 70% methanolic fraction of S. cumini can act as a novel source of natural antioxidant.

The nature of the MDI/wood bond

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marcinko, J.J.; Phanopoulos, C.; Newman, W.H.

1995-12-01

Polymeric diphenylmethane diisocyanate (pMDI) binders have been used in the wood composite industry for 20 years. Almost one half of the oriented strand board (OSB) manufactures in North America are taking advantage of its processing speed and superior board performance. MDI`s current use in Strandboard, MDF (medium density fiber board), LVL (laminated veneer lumber), Plywood, and Particleboard is wide spread. A fundamental understanding of the role of MIDI as a binder in these complex composites is essential for further processing optimization. Experimental data is presented which investigates the nature of the chemical bonding in wood composites. Solid state nuclear magneticmore » resonance (NMR) data is combined with data from thermal analysis and fluorescence microscopy to investigate the chemistry, penetration, and morphology of the isocyanate/wood interphase. Structure property relationships are developed and related to composite performance. The study contrasts isocyanate and phenol formaldehyde binder systems.« less

Microwave and micronization treatments affect dehulling characteristics and bioactive contents of dry beans (Phaseolus vulgaris L.).

PubMed

Oomah, B Dave; Kotzeva, Lily; Allen, Meghan; Bassinello, Priscila Zaczuk

2014-05-01

Heat pretreatment is considered the first step in grain milling. This study therefore evaluated microwave and micronization heat treatments in improving the dehulling characteristics, phenolic composition and antioxidant and α-amylase activities of bean cultivars from three market classes. Heat treatments improved dehulling characteristics (hull yield, rate coefficient and reduced abrasive hardness index) depending on bean cultivar, whereas treatment effects increased with dehulling time. Micronization increased minor phenolic components (tartaric esters, flavonols and anthocyanins) of all beans but had variable effects on total phenolic content depending on market class. Microwave treatment increased α-amylase inhibitor concentration, activity and potency, which were strongly correlated (r²  = 0.71, P < 0.0001) with the flavonol content of beans. Heat treatment had variable effects on the phenolic composition of bean hulls obtained by abrasive dehulling without significantly altering the antioxidant activity of black and pinto bean hulls. Principal component analysis on 22 constituents analyzed in this study demonstrated the differences in dehulling characteristics and phenolic components of beans and hulls as major factors in segregating the beneficial heat treatment effects. Heat treatment may be useful in developing novel dietary fibers from beans with variable composition and bioactivity with a considerable range of applications as functional food ingredients. © 2013 Society of Chemical Industry.

Prediction of aged red wine aroma properties from aroma chemical composition. Partial least squares regression models.

PubMed

Aznar, Margarita; López, Ricardo; Cacho, Juan; Ferreira, Vicente

2003-04-23

Partial least squares regression (PLSR) models able to predict some of the wine aroma nuances from its chemical composition have been developed. The aromatic sensory characteristics of 57 Spanish aged red wines were determined by 51 experts from the wine industry. The individual descriptions given by the experts were recorded, and the frequency with which a sensory term was used to define a given wine was taken as a measurement of its intensity. The aromatic chemical composition of the wines was determined by already published gas chromatography (GC)-flame ionization detector and GC-mass spectrometry methods. In the whole, 69 odorants were analyzed. Both matrixes, the sensory and chemical data, were simplified by grouping and rearranging correlated sensory terms or chemical compounds and by the exclusion of secondary aroma terms or of weak aroma chemicals. Finally, models were developed for 18 sensory terms and 27 chemicals or groups of chemicals. Satisfactory models, explaining more than 45% of the original variance, could be found for nine of the most important sensory terms (wood-vanillin-cinnamon, animal-leather-phenolic, toasted-coffee, old wood-reduction, vegetal-pepper, raisin-flowery, sweet-candy-cacao, fruity, and berry fruit). For this set of terms, the correlation coefficients between the measured and predicted Y (determined by cross-validation) ranged from 0.62 to 0.81. Models confirmed the existence of complex multivariate relationships between chemicals and odors. In general, pleasant descriptors were positively correlated to chemicals with pleasant aroma, such as vanillin, beta damascenone, or (E)-beta-methyl-gamma-octalactone, and negatively correlated to compounds showing less favorable odor properties, such as 4-ethyl and vinyl phenols, 3-(methylthio)-1-propanol, or phenylacetaldehyde.

Phenolic compounds in ectomycorrhizal interaction of lignin modified silver birch

PubMed Central

Sutela, Suvi; Niemi, Karoliina; Edesi, Jaanika; Laakso, Tapio; Saranpää, Pekka; Vuosku, Jaana; Mäkelä, Riina; Tiimonen, Heidi; Chiang, Vincent L; Koskimäki, Janne; Suorsa, Marja; Julkunen-Tiitto, Riitta; Häggman, Hely

2009-01-01

Background The monolignol biosynthetic pathway interconnects with the biosynthesis of other secondary phenolic metabolites, such as cinnamic acid derivatives, flavonoids and condensed tannins. The objective of this study is to evaluate whether genetic modification of the monolignol pathway in silver birch (Betula pendula Roth.) would alter the metabolism of these phenolic compounds and how such alterations, if exist, would affect the ectomycorrhizal symbiosis. Results Silver birch lines expressing quaking aspen (Populus tremuloides L.) caffeate/5-hydroxyferulate O-methyltransferase (PtCOMT) under the 35S cauliflower mosaic virus (CaMV) promoter showed a reduction in the relative expression of a putative silver birch COMT (BpCOMT) gene and, consequently, a decrease in the lignin syringyl/guaiacyl composition ratio. Alterations were also detected in concentrations of certain phenolic compounds. All PtCOMT silver birch lines produced normal ectomycorrhizas with the ectomycorrhizal fungus Paxillus involutus (Batsch: Fr.), and the formation of symbiosis enhanced the growth of the transgenic plants. Conclusion The down-regulation of BpCOMT in the 35S-PtCOMT lines caused a reduction in the syringyl/guaiacyl ratio of lignin, but no significant effect was seen in the composition or quantity of phenolic compounds that would have been caused by the expression of PtCOMT under the 35S or UbB1 promoter. Moreover, the detected alterations in the composition of lignin and secondary phenolic compounds had no effect on the interaction between silver birch and P. involutus. PMID:19788757

Banana (Musa spp) from peel to pulp: ethnopharmacology, source of bioactive compounds and its relevance for human health.

PubMed

Pereira, Aline; Maraschin, Marcelo

2015-02-03

Banana is a fruit with nutritional properties and also with acclaimed therapeutic uses, cultivated widely throughout the tropics as source of food and income for people. Banana peel is known by its local and traditional use to promote wound healing mainly from burns and to help overcome or prevent a substantial number of illnesses, as depression. This review critically assessed the phytochemical properties and biological activities of Musa spp fruit pulp and peel. A survey on the literature on banana (Musa spp, Musaceae) covering its botanical classification and nomenclature, as well as the local and traditional use of its pulp and peel was performed. Besides, the current state of art on banana fruit pulp and peel as interesting complex matrices sources of high-value compounds from secondary metabolism was also approached. Dessert bananas and plantains are systematic classified into four sections, Eumusa, Rhodochlamys, Australimusa, and Callimusa, according to the number of chromosomes. The fruits differ only in their ploidy arrangement and a single scientific name can be given to all the edible bananas, i.e., Musa spp. The chemical composition of banana's peel and pulp comprise mostly carotenoids, phenolic compounds, and biogenic amines. The biological potential of those biomasses is directly related to their chemical composition, particularly as pro-vitamin A supplementation, as potential antioxidants attributed to their phenolic constituents, as well as in the treatment of Parkinson's disease considering their contents in l-dopa and dopamine. Banana's pulp and peel can be used as natural sources of antioxidants and pro-vitamin A due to their contents in carotenoids, phenolics, and amine compounds, for instance. For the development of a phytomedicine or even an allopathic medicine, e.g., banana fruit pulp and peel could be of interest as raw materials riches in beneficial bioactive compounds. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Antioxidant activities of ficus glomerata (moraceae) leaf gall extracts

PubMed Central

Eshwarappa, Ravi Shankara Birur; Iyer, Shanthi; Subaramaihha, Sundara Rajan; Richard, S Austin; Dhananjaya, Bhadrapura Lakkappa

2015-01-01

An excess production or decreased scavenging of reactive oxygen species (ROS) has been implicated in the pathogenesis of diverse metabolic disorders such as diabetes, cancer, atherosclerosis and neurodegeneration. Hence the antioxidant therapy has gained an utmost importance in the treatment of such diseases linked to free radicals. The medicinal properties of plants have been investigated and explored for their potent antioxidant activities to counteract metabolic disorders. This research highlights the chemical composition and antioxidant potential of leaf gall extracts (aqueous and methanol) of Ficus glomerata (F. glomerata), which is extensively used in the preparation of traditional medications to treat various metabolic diseases. The presences of phenolics, flavonoids, phytosterols, terpenoids and reducing sugars were identified in both the extracts. In comparison to the aqueous extract, the methanol extract had the highest total phenolic and flavonoid content at 370 ± 3.2 mg of gallic acid equivalent per gram of dry weight (mg GAE/g dw) and 155 ± 3.2 mg of quercetin equivalent per gram of dry weight (mg QUE/g dw), respectively. The antioxidant activities of leaf gall extracts were examined using diphenylpicrylhydrazyl (DPPH), Nitric oxide scavenging, hydroxyl scavenging and ferric reducing power (FRAP) methods. In all the methods, the methanolic extract showed higher antioxidant potential than the aqueous extract. A higher content of both total phenolics and flavonoids were found in the methanolic extract and the significantly high antioxidant activity can be positively correlated to the high content of total polyphenols/flavonoids of the methanol extract. The results of this study confirm the folklore use of F. glomerata leaf gall extracts as a natural antioxidant and justify its ethnobotanical use. Further, the results of antioxidant properties encourage the use of F. glomerata leaf gall extracts for medicinal health, functional food and nutraceuticals applications. Future work will be interesting in knowing the chemical composition and better understand the mechanism of action of the antioxidants present for development as drug for its therapeutic application. PMID:25598645

Comparison of Phytochemical Composition and Biological Activities of Rubus ulmifolius Extracts Originating from Four Regions of Tunisia.

PubMed

Tabarki, Sonia; Aouadhi, Chedia; Mechergui, Kaouther; Hammi, Khaoula Mkadmini; Ksouri, Riadh; Raies, Aly; Toumi, Lamjed

2017-01-01

In the current study, the phenolic composition, antioxidant and antimicrobial activities of extracts from Rubus ulmifolius Schott leaves harvested in four localities (Sejnen, Tabarka, Faija and Ain drahem) in Tunisia were investigated for the first time. Great differences were found for the chemical composition, total phenol contents and biological activities among the evaluated extracts. HPLC analysis of methanolic extracts showed that the dominant compounds were kaempferol 3-O-rutinoside and naringenine. In addition, significant correlations were observed between antioxidant activities and phenolic contents. In fact, leaves collected from Sejnen presented higher total phenol content (53.32 mg GAE/g DW) and antioxidant activities (IC 50 = 39.40 mg/l) than the others samples. All extracts showed significant antimicrobial activity against six used bacteria with the inhibition zones diameters and minimal inhibitory concentration values were in the range of 8 - 16 mm and 6.25 - 25 mg/ml, respectively. The highest antimicrobial activities were recorded in Sejnen extract against Gram-positive bacteria. © 2017 Wiley-VHCA AG, Zurich, Switzerland.

Amperometric Biosensor Based on Zirconium Oxide/Polyethylene Glycol/Tyrosinase Composite Film for the Detection of Phenolic Compounds.

PubMed

Ahmad, Nor Monica; Abdullah, Jaafar; Yusof, Nor Azah; Ab Rashid, Ahmad Hazri; Abd Rahman, Samsulida; Hasan, Md Rakibul

2016-06-29

A phenolic biosensor based on a zirconium oxide/polyethylene glycol/tyrosinase composite film for the detection of phenolic compounds has been explored. The formation of the composite film was expected via electrostatic interaction between hexacetyltrimethylammonium bromide (CTAB), polyethylene glycol (PEG), and zirconium oxide nanoparticles casted on screen printed carbon electrode (SPCE). Herein, the electrode was treated by casting hexacetyltrimethylammonium bromide on SPCE to promote a positively charged surface. Later, zirconium oxide was mixed with polyethylene glycol and the mixture was dropped cast onto the positively charged SPCE/CTAB. Tyrosinase was further immobilized onto the modified SPCE. Characterization of the prepared nanocomposite film and the modified SPCE surface was investigated by scanning electron microscopy (SEM), Electrochemical Impedance Spectroscopy (EIS), and Cyclic voltamogram (CV). The developed biosensor exhibits rapid response for less than 10 s. Two linear calibration curves towards phenol in the concentrations ranges of 0.075-10 µM and 10-55 µM with the detection limit of 0.034 µM were obtained. The biosensor shows high sensitivity and good storage stability for at least 30 days.

PICA Variants with Improved Mechanical Properties

NASA Technical Reports Server (NTRS)

Thornton, Jeremy; Ghandehari, Ehson M.; Fan, Wenhong; Stackpoole, Margaret; Chavez-Garcia, Jose

2011-01-01

Phenolic Impregnated Carbon Ablator (PICA) is a member of the family of Lightweight Ceramic Ablators (LCAs) and was developed at NASA Ames Research Center as a thermal protection system (TPS) material for the Stardust mission probe that entered the Earth s atmosphere faster than any other probe or vehicle to date. PICA, carbon fiberform base and phenolic polymer, shows excellent thermal insulative properties at heating rates from about 250 W/sq cm to 1000 W/sq cm. The density of standard PICA - 0.26 g/cu cm to 0.28 g/cu cm - can be changed by changing the concentration of the phenolic resin. By adding polymers to the phenolic resin before curing it is possible to significantly improve the mechanical properties of PICA without significantly increasing the density.

Effect of Sterilization Process and Storage on the Antioxidative Properties of Runner Bean.

PubMed

Wołosiak, Rafał; Drużyńska, Beata; Piecyk, Małgorzata; Majewska, Ewa; Worobiej, Elwira

2018-06-11

In this study, we investigated the effect of standard preservation of bean seeds on changes in contents and activity of their selected components: dry matter, ash, different forms of nitrogen, composition of protein fractions; total phenolics and condensed tannins; ability to chelate iron(II) ions; antiradical activity against ABTS •+ and DPPH • ; and capability for inhibiting autoxidation and enzymatic oxidation of linoleic acid. The conducted technological process caused various changes in contents of nitrogen forms and partial loss of phenolic compounds. The antiradical and antioxidative activity of the extracts decreased significantly, while an increase was observed in their ability to chelate Fe(II). These changes were due to the migration of active compounds to the brine, and to their structural transformations and degradation. Longer storage of the sterilized product caused restoration of part of the antiradical activity of the seeds.

Parameters and kinetics of olive mill wastewater dephenolization by immobilized Rhodotorula glutinis cells.

PubMed

Bozkoyunlu, Gaye; Takaç, Serpil

2014-01-01

Olive mill wastewater (OMW) with total phenol (TP) concentration range of 300-1200 mg/L was treated with alginate-immobilized Rhodotorula glutinis cells in batch system. The effects of pellet properties (diameter, alginate concentration and cell loading (CL)) and operational parameters (initial TP concentration, agitation rate and reusability of pellets) on dephenolization of OMW were studied. Up to 87% dephenolization was obtained after 120 h biodegradations. The utilization number of pellets increased with the addition of calcium ions into the biodegradation medium. The overall effectiveness factors calculated for different conditions showed that diffusional limitations arising from pellet size and pellet composition could be neglected. Mass transfer limitations appeared to be more effective at high substrate concentrations and low agitation rates. The parameters of logistic model for growth kinetics of R. glutinis in OMW were estimated at different initial phenol concentrations of OMW by curve-fitting of experimental data with the model.

Fibre from pumpkin (Cucurbita pepo L.) seeds and rinds: physico-chemical properties, antioxidant capacity and application as bakery product ingredients.

PubMed

Nyam, K L; Lau, M; Tan, C P

2013-04-01

The aims of this study were to determine the proximate composition, functional properties and antioxidant activity of pumpkin seeds and rind. Besides, the effects of dietary fibre in pumpkin seeds and rinds on bread qualities and properties were evaluated. Formulations for bread substituted with 0%, 5% and 10% pumpkin seed and rind, respectively were produced. Sensory evaluation of the prepared bread samples for such attributes as appearance, aroma, flavour, texture and overall acceptability was undertaken. The physical properties of the bread samples, including dough expansion, loaf volume, crumb colour and bread texture, were determined. Proximate analysis and determination of antioxidant activity of the bread samples were also conducted. Crude fibre of the pumpkin seeds and pumpkin rinds was high at 31.48% and 14.83%, respectively. The total phenolic compound (TPC) and DPPH radical scavenging activity for the pumpkin rinds were 38.60 mg GAE/100 g dry weight and 69.38%, respectively, which were higher than those of pumpkin seeds. A 5% level of pumpkin rind bread gave the best overall acceptability and sensory attributes, followed by 5% pumpkin seed bread. Total dietary fibre, total phenolic compound and DPPH radical scavenging activity in breads substituted with 5% pumpkin seed and 5% pumpkin rind flour were higher than the values in control bread. Pumpkin seeds and rinds can be used as dietary fibre sources in bakery.

Phenolic Composition, Antioxidant Capacity and in vitro Cytotoxicity Assessment of Fruit Wines

PubMed Central

Ljevar, Ana; Tomašević, Marina; Radošević, Kristina; Srček, Višnja Gaurina; Ganić, Karin Kovačević

2016-01-01

Summary Fruit wines contain a wide range of phenolic compounds with biological effects, but their composition and potential benefits to human health have been studied to the much lesser extent compared to grape wines. The aim of this research is to study the phenolic profile of different types of fruit wines and to evaluate their antioxidant and biological potential. Commercially available fruit wines from blackberry, cherry, raspberry, blackcurrant, strawberry and apple produced in Croatia were analyzed. To the best of our knowledge, this study represents the first comprehensive screening of Croatian fruit wines. The phenolic characterization was performed by spectrophotometry and HPLC-PDA/MS analysis. The antioxidant capacity was determined using ABTS and FRAP assays, while in vitro biological activity was analyzed by the cytotoxicity assay on human breast (MCF-7), colon (CaCo-2) and cervical (HeLa) cancer cell lines. Among the studied fruit wines, blackberry, cherry and blackcurrant wines contained the highest amount of total phenolics, while the last two also contained the highest amount of total anthocyanins. The analysis of individual phenolic compounds showed distinctive phenolic composition of each type of fruit wine, notably as regards anthocyanins. Blackberry, followed by cherry, raspberry and blackcurrant wines also had a significantly higher antioxidant capacity than strawberry and apple wines. Fruit wines inhibited the growth of human cancer cells in vitro in a dose--dependent manner with differing susceptibility among tested cancer cells. Blackberry, cherry, raspberry and blackcurrant wines in the volume ratio of 10 and 20% showed to be the most effective anti-proliferative agents, with higher susceptibility in HeLa and MCF-7 cells than CaCo-2 cells. PMID:27904404

Transport properties associated with carbon-phenolic ablators

NASA Technical Reports Server (NTRS)

Biolsi, L.

1982-01-01

Entry vehicle heat shields designed for entry into the atmosphere of the outer planets are usually made of carbonaceous material such as carbon-phenolic ablator. Ablative injection of this material is an important mechanism for reducing the heat at the surface of the entry vehicle. Conductive transport properties in the shock layer are important for some entry conditions. The kinetic theory of gases has been used to calculate the transport properties for 17 gaseous species obtained from the ablation of carbon-phenolic heat shields. Results are presented for the pure species and for the gas mixture.

One-pot synthesis of biocompatible Te@phenol formaldehyde resin core-shell nanowires with uniform size and unique fluorescent properties by a synergized soft-hard template process.

PubMed

Qian, Haisheng; Zhu, Enbo; Zheng, Shunji; Li, Zhengquan; Hu, Yong; Guo, Changfa; Yang, Xingyun; Li, Liangchao; Tong, Guoxiu; Guo, Huichen

2010-12-10

One-pot hydrothermal process has been developed to synthesize uniform Te@phenol formaldehyde resin core-shell nanowires with unique fluorescent properties. A synergistic soft-hard template mechanism has been proposed to explain the formation of the core-shell nanowires. The Te@phenol formaldehyde resin core-shell nanowires display unique fluorescent properties, which give strong luminescent emission in the blue-violet and green regions with excitation wavelengths of 270 nm and 402 nm, respectively.

Investigation of the Potential Health Benefits as Lipase Inhibitor and Antioxidant of Leopoldia comosa (L.) Parl.: Variability of Chemical Composition of Wild and Cultivated Bulbs.

PubMed

Marrelli, Mariangela; La Grotteria, Stefania; Araniti, Fabrizio; Conforti, Filomena

2017-09-01

There is a great interest in the nutritional value of vegetables and fruits and how the habitat affects nutritive and biological properties. In vitro studies here reported were performed to evaluate the inhibitory activity of formulations from edible plant on pancreatic lipase. The aim of this study was also to evaluate the biovariability of L. comosa (L.) Parl. bulbs from Italy. The wild bulbs were compared with the same cultivated species that are commonly commercialized to identify samples with the best quality for a potential therapeutic application. Hydroalcoholic extract and polar fraction of wild bulbs showed a very important pancreatic lipase inhibitory activity, with IC 50 values of 0.166 ± 0.005 and 0.153 ± 0.005 mg/mL, respectively. In order to characterize the extracts, gas chromatography associated with mass spectrometry (GC/MS) analysis was performed, revealing the predominance of palmitic acid. Phenolic and flavonoid composition was also evaluated. L. comosa extract obtained from wild bulbs demonstrated both antioxidant and anti-obesity activities that might be attributed to a wide range of present phenolic compounds.

Colonic fermentation of polyphenols from Chilean currants (Ribes spp.) and its effect on antioxidant capacity and metabolic syndrome-associated enzymes.

PubMed

Burgos-Edwards, Alberto; Jiménez-Aspee, Felipe; Theoduloz, Cristina; Schmeda-Hirschmann, Guillermo

2018-08-30

The Chilean wild currants Ribes magellanicum and R. punctatum are a good source of polyphenols. Polyphenolic-enriched extracts (PEEs) from both species were submitted to in vitro colonic fermentation to assess the changes in phenolic composition, antioxidant capacity and inhibition of metabolic syndrome-associated enzymes. The phenolic profiles of the fermented samples showed significant changes after 24 h incubation. Nine metabolites, derived from the microbial fermentation, were tentatively identified, including dihydrocaffeic acid, dihydrocaffeoyl-, dihydroferuloylquinic acid, 1-(3,4-dihydroxyphenyl)-3-(2,4,6-trihydroxyphenyl)propan-2-ol (3,4-diHPP-2-ol), among others. The content of anthocyanins and hydroxycinnamic acids was most affected by simulated colonic conditions, with a loss of 71-92% and 90-100% after 24 h incubation, respectively. The highest antioxidant capacity values (ORAC) were reached after 8 h incubation. The inhibitory activity against the enzyme α-glucosidase was maintained after the fermentation process. Our results show that simulated colonic fermentation exerts significant changes on the polyphenolic composition of these berries, modifying their health-promoting properties. Copyright © 2018 Elsevier Ltd. All rights reserved.

Antioxidant properties, phenolic composition and potentiometric sensor array evaluation of commercial and new blueberry (Vaccinium corymbosum) and bog blueberry (Vaccinium uliginosum) genotypes.

PubMed

Kraujalytė, Vilma; Venskutonis, Petras Rimantas; Pukalskas, Audrius; Česonienė, Laima; Daubaras, Remigijus

2015-12-01

Antioxidant properties of juices of newly bred and known blueberry (Vaccinium corymbosum) genotypes and wild bog blueberry (Vaccinium uliginosum) were evaluated by ABTS(+) scavenging capacity (RSC), ferric reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC), total phenolic content (TPC) and total anthocyanin content (TAC) assays. TPC varied in the range of 0.85-2.81 mg gallic acid equiv./mL, RSC, FRAP and ORAC values were 6.38-20.9, 3.07-17.8 and 4.21-45.68 μmol Trolox equiv./g, respectively. New blueberry genotypes and bog blueberry demonstrated stronger antioxidant properties and TAC than other studied genotypes. The content of quinic (203-3614 μg/mL), chlorogenic (20.0-346.8 μg/mL) acids and rutin (0.00-26.88 μg/mL) measured by UPLC/ESI-QTOF-MS varied depending on the genotype. Juices were evaluated by electronic tongue; PCA score plot showed that the method discriminates different genotypes although some juice samples were located very closely and overlapping. Significant differences were observed between L(∗), a(∗), b(∗) colour parameters of some genotypes. Copyright © 2015 Elsevier Ltd. All rights reserved.

Elemental composition and optical properties reveal changes in dissolved organic matter along a permafrost thaw chronosequence in a subarctic peatland

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hodgkins, Suzanne B.; Tfaily, Malak M.; Podgorski, David C.

2016-08-01

The fate of carbon stored in permafrost-zone peatlands represents a significant uncertainty in global climate modeling. Given that the breakdown of dissolved organic matter (DOM) is often a major pathway for decomposition in peatlands, knowledge of DOM reactivity under different permafrost regimes is critical for determining future climate feedbacks. To explore the effects of permafrost thaw and resultant plant succession on DOM reactivity, we used a combination of Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), UV/Vis absorbance, and excitation-emission matrix spectroscopy (EEMS) to examine the DOM elemental composition and optical properties of 27 pore water samples gathered frommore » various sites along a permafrost thaw sequence in Stordalen Mire, a thawing subarctic peatland in northern Sweden. The presence of dense Sphagnum moss, a feature that is dominant in the intermediate thaw stages, appeared to be the main driver of variation in DOM elemental composition and optical properties at Stordalen. Specifically, DOM from sites with Sphagnum had greater aromaticity, higher average molecular weights, and greater O/C, consistent with a higher abundance of phenolic compounds that likely inhibit decomposition. These compounds are released by Sphagnum and may accumulate due to inhibition of phenol oxidase activity by the acidic pH at these sites. In contrast, sites without Sphagnum, specifically fully-thawed rich fens, had more saturated, more reduced compounds, which were high in N and S. Optical properties at rich fens were indicated the presence of microbially-derived DOM, consistent with the higher decomposition rates previously measured at these sites. These results indicate that Sphagnum acts as an inhibitor of rapid decomposition and CH4 release in thawing subarctic peatlands, consistent with lower rates of CO2 and CH4 production previously observed at these sites. However, this inhibitory effect may disappear if Sphagnumdominated bogs transition to more waterlogged rich fens that contain very little to no living Sphagnum. Release of this inhibition allows for higher levels of microbial activity and potentially greater CH4 release, as has been observed in these fen sites.« less

Elemental composition and optical properties reveal changes in dissolved organic matter along a permafrost thaw chronosequence in a subarctic peatland

NASA Astrophysics Data System (ADS)

Hodgkins, Suzanne B.; Tfaily, Malak M.; Podgorski, David C.; McCalley, Carmody K.; Saleska, Scott R.; Crill, Patrick M.; Rich, Virginia I.; Chanton, Jeffrey P.; Cooper, William T.

2016-08-01

The fate of carbon stored in permafrost-zone peatlands represents a significant uncertainty in global climate modeling. Given that the breakdown of dissolved organic matter (DOM) is often a major pathway for decomposition in peatlands, knowledge of DOM reactivity under different permafrost regimes is critical for determining future climate feedbacks. To explore the effects of permafrost thaw and resultant plant succession on DOM reactivity, we used a combination of Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), UV/Vis absorbance, and excitation-emission matrix spectroscopy (EEMS) to examine the DOM elemental composition and optical properties of 27 pore water samples gathered from various sites along a permafrost thaw sequence in Stordalen Mire, a thawing subarctic peatland in northern Sweden. The presence of dense Sphagnum moss, a feature that is dominant in the intermediate thaw stages, appeared to be the main driver of variation in DOM elemental composition and optical properties at Stordalen. Specifically, DOM from sites with Sphagnum had greater aromaticity, higher average molecular weights, and greater O/C, consistent with a higher abundance of phenolic compounds that likely inhibit decomposition. These compounds are released by Sphagnum and may accumulate due to inhibition of phenol oxidase activity by the acidic pH at these sites. In contrast, sites without Sphagnum, specifically fully-thawed rich fens, had more saturated, more reduced compounds, which were high in N and S. Optical properties at rich fens indicated the presence of microbially-derived DOM, consistent with the higher decomposition rates previously measured at these sites. These results indicate that Sphagnum acts as an inhibitor of rapid decomposition and CH4 release in thawing subarctic peatlands, consistent with lower rates of CO2 and CH4 production previously observed at these sites. However, this inhibitory effect may disappear if Sphagnum-dominated bogs transition to more waterlogged rich fens that contain very little to no living Sphagnum. Release of this inhibition allows for higher levels of microbial activity and potentially greater CH4 release, as has been observed in these fen sites.

Effect of processing on phenolic acids composition and radical scavenging capacity of barley pasta.

PubMed

De Paula, Rosanna; Rabalski, Iwona; Messia, Maria Cristina; Abdel-Aal, El-Sayed M; Marconi, Emanuele

2017-12-01

Phenolic acids, total phenolics content and DPPH radical scavenging capacity in raw ingredients, fresh and dried spaghetti, and in uncooked and cooked spaghetti were evaluated and compared with semolina spaghetti as a reference. Ferulic acid was the major phenolic acid found in the free and bound phenolic extracts in all the investigated pasta samples. The addition of barley flour into pasta at incorporation levels of 30, 50 and 100% increased phenolic acids and total phenolics content. Pasta processing did not significantly affect the total phenolics content and free radical scavenging capacity, but a significant reduction in total phenolic acids measured by HPLC was found. Drying process differently affected individual phenolic compounds in the free and bound fractions, and thus, the total phenolic acids content. Free vanillic, caffeic and p-coumaric acids did not significantly change, while p-hydroxybenzoic and ferulic acids of the free extracts showed higher values compared to the corresponding fresh pasta. Cooking did not greatly affect total phenolic acids, more leading to conserving free and bound phenolic compounds. Copyright © 2017 Elsevier Ltd. All rights reserved.

Opuntia spp.: Characterization and Benefits in Chronic Diseases.

PubMed

Del Socorro Santos Díaz, María; Barba de la Rosa, Ana-Paulina; Héliès-Toussaint, Cécile; Guéraud, Françoise; Nègre-Salvayre, Anne

2017-01-01

Opuntia species have been used for centuries as food resources and in traditional folk medicine for their nutritional properties and their benefit in chronic diseases, particularly diabetes, obesity, cardiovascular diseases, and cancer. These plants are largely distributed in America, Africa, and the Mediterranean basin. Opuntia spp. have great economic potential because they grow in arid and desert areas, and O. ficus-indica , the domesticated O . species, is used as a nutritional and pharmaceutical agent in various dietary and value-added products. Though differences in the phytochemical composition exist between wild and domesticated ( O. ficus-indica ) Opuntia spp., all Opuntia vegetatives (pear, roots, cladodes, seeds, and juice) exhibit beneficial properties mainly resulting from their high content in antioxidants (flavonoids, ascorbate), pigments (carotenoids, betalains), and phenolic acids. Other phytochemical components (biopeptides, soluble fibers) have been characterized and contribute to the medicinal properties of Opuntia spp. The biological properties of Opuntia spp. have been investigated on cellular and animal models and in clinical trials in humans, allowing characterization and clarification of the protective effect of Opuntia -enriched diets in chronic diseases. This review is an update on the phytochemical composition and biological properties of Opuntia spp. and their potential interest in medicine.

Opuntia spp.: Characterization and Benefits in Chronic Diseases

PubMed Central

del Socorro Santos Díaz, María; Barba de la Rosa, Ana-Paulina; Héliès-Toussaint, Cécile; Guéraud, Françoise

2017-01-01

Opuntia species have been used for centuries as food resources and in traditional folk medicine for their nutritional properties and their benefit in chronic diseases, particularly diabetes, obesity, cardiovascular diseases, and cancer. These plants are largely distributed in America, Africa, and the Mediterranean basin. Opuntia spp. have great economic potential because they grow in arid and desert areas, and O. ficus-indica, the domesticated O. species, is used as a nutritional and pharmaceutical agent in various dietary and value-added products. Though differences in the phytochemical composition exist between wild and domesticated (O. ficus-indica) Opuntia spp., all Opuntia vegetatives (pear, roots, cladodes, seeds, and juice) exhibit beneficial properties mainly resulting from their high content in antioxidants (flavonoids, ascorbate), pigments (carotenoids, betalains), and phenolic acids. Other phytochemical components (biopeptides, soluble fibers) have been characterized and contribute to the medicinal properties of Opuntia spp. The biological properties of Opuntia spp. have been investigated on cellular and animal models and in clinical trials in humans, allowing characterization and clarification of the protective effect of Opuntia-enriched diets in chronic diseases. This review is an update on the phytochemical composition and biological properties of Opuntia spp. and their potential interest in medicine. PMID:28491239

Bean cultivars (Phaseolus vulgaris L.) have similar high antioxidant capacity, in vitro inhibition of alpha-amylase and alpha-glucosidase while diverse phenolic composition and concentration

USDA-ARS?s Scientific Manuscript database

Common beans are a good source of essential nutrients such as protein, fiber, vitamins, and minerals; they also contain phenolic compounds and other phytochemicals. Phenolic compounds exhibit high antioxidant capacity that promotes health benefits by reducing oxidative stress. The objective was to c...

Chemometric compositional analysis of phenolic compounds in fermenting samples and wines using different infrared spectroscopy techniques.

PubMed

Aleixandre-Tudo, Jose Luis; Nieuwoudt, Helene; Aleixandre, Jose Luis; du Toit, Wessel

2018-01-01

The wine industry requires reliable methods for the quantification of phenolic compounds during the winemaking process. Infrared spectroscopy appears as a suitable technique for process control and monitoring. The ability of Fourier transform near infrared (FT-NIR), attenuated total reflectance mid infrared (ATR-MIR) and Fourier transform infrared (FT-IR) spectroscopies to predict compositional phenolic levels during red wine fermentation and aging was investigated. Prediction models containing a large number of samples collected over two vintages from several industrial fermenting tanks as well as wine samples covering a varying number of vintages were validated. FT-NIR appeared as the most accurate technique to predict the phenolic content. Although slightly less accurate models were observed, ATR-MIR and FT-IR can also be used for the prediction of the majority of phenolic measurements. Additionally, the slope and intercept test indicated a systematic error for the three spectroscopies which seems to be slightly more pronounced for HPLC generated phenolics data than for the spectrophotometric parameters. However, the results also showed that the predictions made with the three instruments are statistically comparable. The robustness of the prediction models was also investigated and discussed. Copyright © 2017 Elsevier B.V. All rights reserved.

Eggplant fruit composition as affected by the cultivation environment and genetic constitution.

PubMed

San José, Raquel; Sánchez-Mata, María-Cortes; Cámara, Montaña; Prohens, Jaime

2014-10-01

No comprehensive reports exist on the combined effects of season, cultivation environment and genotype on eggplant (Solanum melongena) composition. We studied proximate composition, carbohydrates, total phenolics and vitamin C of eggplant fruits of three Spanish landraces, three commercial hybrids and three hybrids between landraces cultivated across two environmental conditions (open field, OF; and, greenhouse, GH) for up to four seasons. Season (S) had a larger effect than the genotype (G) for composition traits, except for total phenolics. G × S interaction was generally of low relative magnitude. Orthogonal decomposition of the season effect showed that differences within OF or GH environments were in many instances greater than those between OF and GH. Spanish landraces presented, on average, lower contents of total carbohydrates and starch and higher contents of total vitamin C, ascorbic acid, and total phenolics than commercial hybrids. Hybrids among landraces presented variable levels of heterosis for composition traits. Genotypes grown in the same season cluster together on the graph of multivariate principal components analysis. The cultivation environment has a major role in determining the composition of eggplant fruits. Environmental and genotypic differences can be exploited to obtain high quality eggplant fruits.

Phenolic Profile and Biological Activities of the Pepino (Solanum muricatum) Fruit and Its Wild Relative S. caripense

PubMed Central

Herraiz, Francisco J.; Villaño, Débora; Plazas, Mariola; Vilanova, Santiago; Ferreres, Federico; Prohens, Jaime; Moreno, Diego A.

2016-01-01

The pepino (Solanum muricatum) is an edible and juicy fruit native to the Andean region which is becoming increasingly important. However, little information is available on its phenolic composition and bioactive properties. Four pepino varieties (37-A, El Camino, Puzol, and Valencia) and one accession (E-7) of its close wild relative S. caripense were characterized by HPLC-DAD-MSn/ESI. Twenty-four hydroxycinnamic acid derivatives were detected (5 to 16 compounds per variety or accession), with differences of more than two-fold for their total content among the materials studied. The major phenolics in the pepino varieties were chlorogenic acids and derivatives, while in S. caripense a caffeoyl-synapoyl-quinic acid was the major compound. The in vitro antioxidant capacity (DPPH (2,2-diphenyl-1-picrylhydrazyl hydrate), ORAC (oxygen radical absorbance capacity), and TRC (total reducing capacity) tests) was higher in S. caripense. Pepino and S. caripense extracts were not toxic for RAW 264.7 macrophage cells, and the raw extracts inhibited NO production of the lipopolysaccharide (LPS)-stimulated macrophages by 36% (El Camino) to 67% (37-A). No single variety ranked high simultaneously for hydroxycinnamic acids content, antioxidant activity and biological activity. We suggest the screening of large collections of germplasm or the use of complementary crosses between Puzol (high for hydroxycinnamic acids and biological activity) and S. caripense E-7 (high for antioxidant activity) to select and breed pepino varieties with enhanced properties. PMID:26999114

Antioxidant Property Enhancement of Sweet Potato Flour under Simulated Gastrointestinal pH

PubMed Central

Chan, Kim Wei; Khong, Nicholas M. H.; Iqbal, Shahid; Umar, Imam Mustapha; Ismail, Maznah

2012-01-01

Sweet potato is known to be rich in healthful antioxidants, but the stability of its antioxidant properties under gastrointestinal pH is very much unknown. Hence, this study aimed to evaluate the changes in antioxidant properties (total contents of phenolics and flavonoids as well as antioxidant activity) of sweet potato flour (SPF) under simulated gastrointestinal pH conditions. It was found that the yield of SPF crude phenolic extract increased from 0.29 to 3.22 g/100 g SPF upon subjection to gastrointestinal pH conditions (p < 0.05). Also elevated significantly were the total phenolic content (TPC), total flavonoid content (TFC) and antioxidant activity of SPF (p < 0.05). In summary, the antioxidant properties of SPF were enhanced under gastrointestinal pH conditions, suggesting that SPF might possess a considerable amount of bound phenolic and other antioxidative compounds. The antioxidant properties of SPF are largely influenced by pH and thus might be enhanced during the in vivo digestive process. PMID:22942747

Cultivar Diversity of Grape Skin Polyphenol Composition and Changes in Response to Drought Investigated by LC-MS Based Metabolomics

PubMed Central

Pinasseau, Lucie; Vallverdú-Queralt, Anna; Verbaere, Arnaud; Roques, Maryline; Meudec, Emmanuelle; Le Cunff, Loïc; Péros, Jean-Pierre; Ageorges, Agnès; Sommerer, Nicolas; Boulet, Jean-Claude; Terrier, Nancy; Cheynier, Véronique

2017-01-01

Phenolic compounds represent a large family of plant secondary metabolites, essential for the quality of grape and wine and playing a major role in plant defense against biotic and abiotic stresses. Phenolic composition is genetically driven and greatly affected by environmental factors, including water stress. A major challenge for breeding of grapevine cultivars adapted to climate change and with high potential for wine-making is to dissect the complex plant metabolic response involved in adaptation mechanisms. A targeted metabolomics approach based on ultra high-performance liquid chromatography coupled to triple quadrupole mass spectrometry (UHPLC-QqQ-MS) analysis in the Multiple Reaction Monitoring (MRM) mode has been developed for high throughput profiling of the phenolic composition of grape skins. This method enables rapid, selective, and sensitive quantification of 96 phenolic compounds (anthocyanins, phenolic acids, stilbenoids, flavonols, dihydroflavonols, flavan-3-ol monomers, and oligomers…), and of the constitutive units of proanthocyanidins (i.e., condensed tannins), giving access to detailed polyphenol composition. It was applied on the skins of mature grape berries from a core-collection of 279 Vitis vinifera cultivars grown with or without watering to assess the genetic variation for polyphenol composition and its modulation by irrigation, in two successive vintages (2014–2015). Distribution of berry weights and δ13C values showed that non irrigated vines were subjected to a marked water stress in 2014 and to a very limited one in 2015. Metabolomics analysis of the polyphenol composition and chemometrics analysis of this data demonstrated an influence of water stress on the biosynthesis of different polyphenol classes and cultivar differences in metabolic response to water deficit. Correlation networks gave insight on the relationships between the different polyphenol metabolites and related biosynthetic pathways. They also established patterns of polyphenol response to drought, with different molecular families affected either positively or negatively in the different cultivars, with potential impact on grape and wine quality. PMID:29163566

Influence of doum (Hyphaene thebaica L.) flour addition on dough mixing properties, bread quality and antioxidant potential.

PubMed

Aboshora, Waleed; Lianfu, Zhang; Dahir, Mohammed; Qingran, Meng; Musa, Abubakr; Gasmalla, Mohammed A A; Omar, Khamis Ali

2016-01-01

In this covenant of functional foods, the world seeks for new healthier food products with appropriate proportions of bioactive constituents such as fiber, mineral elements, phenols and flavonoids. The doum fruit has good nutritional and pharmaceutical properties; therefore, its incorporation in breads could be beneficial in improving human health. In the current study, partial substitution of wheat flour (WF) with doum fruit flour (DFF) at levels of 5 %, 10 %, 15 % and 20 % were carried out to investigate the dough viscoelastic properties, baking performance, proximate compositions and antioxidant properties of the breads. Partial substitution of WF with DFF increased the water absorption and developing time of dough (P ≤ 0.05), while, the dough extensibility, resistance to extension and the deformation energy were reduced. Bread supplemented with DFF resulted in a reduction in quality in terms of specific loaf volume, conferred softness, hardness, cohesiveness and gumminess to the bread crumbs. DFF up to 15 % could partially replace WF in bread; increase its nutritional value in terms of fiber content and minerals, with only a small depreciation in the bread quality. Sensory evaluation showed that breads supplemented up to 15 % DFF were acceptable to the panelists and there was no significant difference in terms of taste, texture and overall acceptability compared to the control. The incorporation of DFF increased the total phenolic contents, total flavonoids contents and antioxidant properties compared to the control (for both flour and bread).

Bioreactor microbial ecosystems with differentiated methanogenic phenol biodegradation and competitive metabolic pathways unraveled with genome-resolved metagenomics.

PubMed

Ju, Feng; Wang, Yubo; Zhang, Tong

2018-01-01

Methanogenic biodegradation of aromatic compounds depends on syntrophic metabolism. However, metabolic enzymes and pathways of uncultured microorganisms and their ecological interactions with methanogenic consortia are unknown because of their resistance to isolation and limited genomic information. Genome-resolved metagenomics approaches were used to reconstruct and dissect 23 prokaryotic genomes from 37 and 20 °C methanogenic phenol-degrading reactors. Comparative genomic evidence suggests that temperature difference leads to the colonization of two distinct cooperative sub-communities that can respire sulfate/sulfite/sulfur or nitrate/nitrite compounds and compete for uptake of methanogenic substrates (e.g., acetate and hydrogen). This competition may differentiate methanogenesis. The uncultured ε - Proteobacterium G1, whose close relatives have broad ecological niches including the deep-sea vents, aquifers, sediment, limestone caves, spring, and anaerobic digesters, is implicated as a Sulfurovum -like facultative anaerobic diazotroph with metabolic versatility and remarkable environmental adaptability. We provide first genomic evidence for butyrate, alcohol, and carbohydrate utilization by a Chloroflexi T78 clade bacterium, and phenol carboxylation and assimilatory sulfite reduction in a Cryptanaerobacter bacterium. Genome-resolved metagenomics enriches our view on the differentiation of microbial community composition, metabolic pathways, and ecological interactions in temperature-differentiated methanogenic phenol-degrading bioreactors. These findings suggest optimization strategies for methanogenesis on phenol, such as temperature control, protection from light, feed desulfurization, and hydrogen sulfide removal from bioreactors. Moreover, decoding genome-borne properties (e.g., antibiotic, arsenic, and heavy metal resistance) of uncultured bacteria help to bring up alternative schemes to isolate them.

The paradoxical effect of extra-virgin olive oil on oxidative phenomena during in vitro co-digestion with meat.

PubMed

Martini, Serena; Cavalchi, Martina; Conte, Angela; Tagliazucchi, Davide

2018-07-01

Extra-virgin olive oil is an integral part of the Mediterranean diet and its consumption has been associated with a reduction risk of chronic diseases. Here we tested the potential of extra-virgin olive oil to limit the oxidative phenomena during in vitro gastro-intestinal co-digestion with turkey breast meat. The extra-virgin olive oil was particularly rich in oleuropein aglycone isomers, which represented the 66.8% of total phenolic determined with MS/MS experiments. Meals supplemented with extra-virgin olive oil equivocally affected lipid peroxidation. At low concentration (2.5% respect to meat), a significant inhibition of lipid oxidation was observed, whereas lipid peroxidation was greatly enhanced when the amount of extra-virgin olive oil was increased in the gastro-intestinal system. The inhibitory effect observed at 2.5% extra-virgin olive oil was due to the antioxidant properties of extra-virgin olive oil phenolic compounds. At high concentration, extra-virgin olive oil phenolic compounds (especially hydroxytyrosol-derivative) behaved as pro-oxidants increasing the generation of lipid hydroperoxides from meat. At the same time, the presence in the digestive system of catalysers from meat induced the peroxidation of extra-virgin olive oil fatty acids, which was further intensified by the pro-oxidant activity of extra-virgin olive oil phenolic compounds. Our study underlined the importance of the timing and amount of consumption of extra-virgin olive oil as well as its phenolic composition in limiting the peroxidative phenomena on meat lipids during digestion. Copyright © 2018 Elsevier Ltd. All rights reserved.

Tailoring Dielectric and Actuated Properties of Elastomer Composites by Bioinspired Poly(dopamine) Encapsulated Graphene Oxide.

PubMed

Ning, Nanying; Ma, Qin; Liu, Suting; Tian, Ming; Zhang, Liqun; Nishi, Toshio

2015-05-27

In this study, we obtained dielectric elastomer composites with controllable dielectric and actuated properties by using a biomimetic method. We used dopamine (DA) to simultaneously coat the graphene oxide (GO) and partially reduce GO by self-polymerization of DA on GO. The poly(dopamine) (PDA) coated GO (GO-PDA) was assembled around rubber latex particles by hydrogen bonding interaction between carboxyl groups of carboxylated nitrile rubber (XNBR) and imino groups or phenolic hydroxyl groups of GO-PDA during latex compounding, forming a segregated GO-PDA network at a low percolation threshold. The results showed that the introduction of PDA on GO prevented the restack of GO in the matrix. The dielectric and actuated properties of the composites depend on the thickness of PDA shell. The dielectric loss and the elastic modulus decrease, and the breakdown strength increases with increasing the thickness of PDA shell. The maximum actuated strain increases from 1.7% for GO/XNBR composite to 4.4% for GO-PDA/XNBR composites with the PDA thickness of about 5.4 nm. The actuated strain at a low electric field (2 kV/mm) obviously increases from 0.2% for pure XNBR to 2.3% for GO-PDA/XNBR composite with the PDA thickness of 1.1 nm, much higher than that of other DEs reported in previous studies. Thus, we successfully obtained dielectric composites with low dielectric loss and improved breakdown strength and actuated strain at a low electric field, facilitating the wide application of dielectric elastomers.

Phenolic Composition and Antioxidant Activity of Malus domestica Leaves

PubMed Central

Viškelis, Pranas; Uselis, Norbertas

2014-01-01

The aim of this study was to determine the composition and content of phenolic compounds in the ethanol extracts of apple leaves and to evaluate the antioxidant activity of these extracts. The total phenolic content was determined spectrophotometrically, as well as the total flavonoid content in the ethanol extracts of apple leaves and the antioxidant activity of these extracts, by the ABTS, DPPH, and FRAP assays. The highest amount of phenolic compounds and flavonoids as well as the highest antioxidant activity was determined in the ethanol extracts obtained from the apple leaves of the cv. Aldas. The analysis by the HPLC method revealed that phloridzin was a predominant component in the ethanol extracts of the apple leaves of all cultivars investigated. The following quercetin glycosides were identified and quantified in the ethanol extracts of apple leaves: hyperoside, isoquercitrin, avicularin, rutin, and quercitrin. Quercitrin was the major compound among quercetin glycosides. PMID:25302319

Phenolic composition and antioxidant activity of Malus domestica leaves.

PubMed

Liaudanskas, Mindaugas; Viškelis, Pranas; Raudonis, Raimondas; Kviklys, Darius; Uselis, Norbertas; Janulis, Valdimaras

2014-01-01

The aim of this study was to determine the composition and content of phenolic compounds in the ethanol extracts of apple leaves and to evaluate the antioxidant activity of these extracts. The total phenolic content was determined spectrophotometrically, as well as the total flavonoid content in the ethanol extracts of apple leaves and the antioxidant activity of these extracts, by the ABTS, DPPH, and FRAP assays. The highest amount of phenolic compounds and flavonoids as well as the highest antioxidant activity was determined in the ethanol extracts obtained from the apple leaves of the cv. Aldas. The analysis by the HPLC method revealed that phloridzin was a predominant component in the ethanol extracts of the apple leaves of all cultivars investigated. The following quercetin glycosides were identified and quantified in the ethanol extracts of apple leaves: hyperoside, isoquercitrin, avicularin, rutin, and quercitrin. Quercitrin was the major compound among quercetin glycosides.

Variability in the composition of phenolic compounds in winter-dormant Salix pyrolifolia in relation to plant part and age.

PubMed

Lavola, Anu; Maukonen, Merja; Julkunen-Tiitto, Riitta

2018-06-12

The phenolic phytochemicals of winter-dormant Salix pyrolifolia were determined from the vegetative buds, and the bark and wood of different-aged twigs by HPLC-DAD and UHPLC-QTOF-MS analyses. All the plant parts were composed of salicylate glucosides and the other Salix-specific, simple phenolic glucosides as well as of phenolic acids, flavonoids and the high molecular-weight condensed tannins. The flavonoid composition was most diverse in buds and they also contained a large amount of chlorogenic acid (5-caffeoylquinic acid IUPAC), while salicylate glucosides and simple phenolic glucosides predominated in bark. The wooden interior part of the twigs contained fewer components and the lowest concentrations of compounds. Salicortin was the main compound in winter-dormant S. pyrolifolia (over 10% of bark biomass), but the concentrations of picein, salireposide, isosalipurposide, catechin and condensed tannins were also high. The flavonoid composition was highly naringenin- and quercetin-biassed. The composition of phytochemicals was organ-specific and remained relatively similar between different-aged trees. However, there were compound-specific fluctuations in the concentrations of phytochemicals with the age of the trees and within plant parts. Generally, the one-year-old plants differed from the older trees in their high concentration of condensed tannins in all the plant parts studied and in the highest concentration of isosalipurposide in bark, while the total amounts of salicylate glucosides in plant parts, and of naringenin glucosides in buds, tended to be highest in 20 year-old-trees. Copyright © 2018 Elsevier Ltd. All rights reserved.

A review of phenolic compounds in oil-bearing plants: Distribution, identification and occurrence of phenolic compounds.

PubMed

Alu'datt, Muhammad H; Rababah, Taha; Alhamad, Mohammad N; Al-Mahasneh, Majdi A; Almajwal, Ali; Gammoh, Sana; Ereifej, Khalil; Johargy, Ayman; Alli, Inteaz

2017-03-01

Over the last two decades, separation, identification and measurement of the total and individual content of phenolic compounds has been widely investigated. Recently, the presence of a wide range of phenolic compounds in oil-bearing plants has been shown to contribute to their therapeutic properties, including anti-cancer, anti-viral, anti-oxidant, hypoglycemic, hypo-lipidemic, and anti-inflammatory activities. Phenolics in oil-bearing plants are now recognized as important minor food components due to several organoleptic and health properties, and they are used as food or sources of food ingredients. Variations in the content of phenolics in oil-bearing plants have largely been attributed to several factors, including the cultivation, time of harvest and soil types. A number of authors have suggested that the presence phenolics in extracted proteins, carbohydrates and oils may contribute to objectionable off flavors The objective of this study was to review the distribution, identification and occurrence of free and bound phenolic compounds in oil-bearing plants. Copyright © 2016 Elsevier Ltd. All rights reserved.

Chemical composition and biological activities of a phenol-water extract from Haemophilus influenzae type a.

PubMed Central

Raichvarg, D; Brossard, C; Agneray, J

1979-01-01

Ribonucleic acid was removed from a phenol-water extract of Haemophilus influenzae type a by streptomycin sulfate. This preparation was called purified preparation or PP. It contained neutral sugars (glucose, galactose, mannose, pentose), glucosamine, amino acids, and fatty acids. Heptose and 2-keto-3-deoxyoctonic acid were not present. The biological properties and immunogenicity were compared with the activities of lipopolysaccharide of Escherichia coli or Salmonella typhimurium. Higher doses were necessary to obtain lethality in mice and Sanarelli and Shwartzman reactions with our preparations than were necessary with lipopolysaccharide. The Limulus test and pyrogen assay in rabbits gave the same results with purified preparation and lipopolysaccharide, but pyrogenicity of purified preparation was not destroyed by NaOH treatment. Purified preparation was not as immunogenic at low doeses for rabbits as lipopolysaccharide. The results were different from those obtained with lipopolysaccharide but similar to those known from peptidoglycan studies. The contamination of purified preparation with peptidoglycan was negligible and cannot explain the biological activities of purified preparation. We suggest that the phenol-water extract from H. influenzae is not a classical endotoxin, but rather an endotoxin-like substance. PMID:317593

Bioactive compounds in pindo palm (Butia capitata) juice and in pomace resulting of the extraction process.

PubMed

Jachna, Tiphaine J; Hermes, Vanessa S; Flôres, Simone H; Rios, Alessandro O

2016-03-15

Pindo palm (Butia capitata, Becc. 1916) is a tropical fruit native to South America and is relatively rich in bioactive compounds. It is often consumed as juice. The aim of this study was, first, to identify the degradation of these compounds by pasteurization and by cold storage (4 °C) of pindo palm juice. Physicochemical properties and concentrations of phenolic compounds, carotenoids and vitamin C have been evaluated on fresh and pasteurized juices. Moreover, another objective was to characterize the nutritional composition and the bioactive compounds of pindo palm pomace, the by-product of juice processing. The results demonstrated a degradation of carotenoids with pasteurization and a degradation of vitamin C with both pasteurization and cold storage of juices. Furthermore, the evaluation of pindo palm pomace showed that it is relatively rich in total phenols (20.06 g gallic acid equivalents kg(-1) dry matter) and in β-carotene (0.22 g kg(-1) dry matter). Thus, from the nutrition viewpoint, it does not seem interesting to pasteurize juice. On the other hand, extraction of carotenoids and phenolic compounds from the pomace appears to be a relevant process. © 2015 Society of Chemical Industry.

Semisynthetic Phenol Derivatives Obtained from Natural Phenols: Antimicrobial Activity and Molecular Properties.

PubMed

Pinheiro, Patrícia Fontes; Menini, Luciana Alves Parreira; Bernardes, Patrícia Campos; Saraiva, Sérgio Henriques; Carneiro, José Walkimar Mesquita; Costa, Adilson Vidal; Arruda, Társila Rodrigues; Lage, Mateus Ribeiro; Gonçalves, Patrícia Martins; Bernardes, Carolina de Oliveira; Alvarenga, Elson Santiago; Menini, Luciano

2018-01-10

Semisynthetic phenol derivatives were obtained from the natural phenols: thymol, carvacrol, eugenol, and guaiacol through catalytic oxychlorination, Williamson synthesis, and aromatic Claisen rearrangement. The compounds characterization was carried out by 1 H NMR, 13 C NMR, and mass spectrometry. The natural phenols and their semisynthetic derivatives were tested for their antimicrobial activity against the bacteria: Staphylococcus aureus, Escherichia coli, Listeria innocua, Pseudomonas aeruginosa, Salmonella enterica Typhimurium, Salmonella enterica ssp. enterica, and Bacillus cereus. Minimum inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) values were determined using concentrations from 220 to 3.44 μg mL -1 . Most of the tested compounds presented MIC values ≤220 μg mL -1 for all the bacteria used in the assays. The molecular properties of the compounds were computed with the PM6 method. Through principle components analysis, the natural phenols and their semisynthetic derivatives with higher antimicrobial potential were grouped.

Apple juice composition: sugar, nonvolatile acid, and phenolic profiles.

PubMed

Lee, H S; Wrolstad, R E

1988-01-01

Apples from Michigan, Washington, Argentina, Mexico, and New Zealand were processed into juice; the 8 samples included Golden Delicious, Jonathan, Granny Smith, and McIntosh varieties. Liquid chromatography was used for quantitation of sugars (glucose, fructose, sucrose, and sorbitol), nonvolatile acids (malic, quinic, citric, shikimic, and fumaric), and phenolics (chlorogenic acid and hydroxymethylfurfural [HMF]). Other determinations included pH, 0Brix, and L-malic acid. A number of compositional indices for these authentic juices, e.g., chlorogenic acid content, total malic - L-malic difference, and the HMF:chlorogenic ratio, were at variance with recommended standards. The phenolic profile was shown to be particularly influenced by gelatin fining, with peak areas decreasing by as much as 50%. The L-malic:total malic ratio serves as a better index for presence of synthetic malic acid than does the difference between the 2 determinations. No apparent differences in chemical composition could be attributed to geographic origin.

Biodegradation of Phenolic Contaminants: Current Status and Perspectives

NASA Astrophysics Data System (ADS)

Zhao, Lin; Wu, Qi; Ma, Aijin

2018-01-01

Phenolic compounds, a class of toxic pollutants in water, come mainly from a variety of industrial processes. The industrial application for biodegradation has become an important topic in recent years. In this review, we discuss the present situation, properties, and pollution characteristics of phenolic contaminants, factors affecting the degradation of phenols, microbial species and biodegradation methods. The challenges and opportunities in developing biodegradation processes of phenolic contaminants are also discussed.

Micromechanical simulation of damage progression in carbon phenolic composites

NASA Technical Reports Server (NTRS)

Slattery, Kerry T.

1993-01-01

Carbon/phenolic composites are used extensively as ablative insulating materials in the nozzle region of solid rocket motors. The current solid rocket motor (RSRM) on the space shuttle is fabricated from woven rayon cloth which is carbonized and then impregnated with the phenolic resin. These plies are layed up in the desired configuration and cured to form the finished part. During firing, the surface of the carbon/phenolic insulation is exposed to 5000 F gases from the rocket exhaust. The resin pyrolizes and the material chars to a depth which progresses with time. The rate of charring and erosion are generally predictable, and the insulation depth is designed to allow adequate safety margins over the firing time of the motor. However, anomalies in the properties and response of the carbon/phenolic materials can lead to severe material damage which may decrease safety margins to unacceptable levels. Three macro damage modes which were observed in fired nozzles are: ply lift, 'wedge out', and pocketing erosion. Ply lift occurs in materials with plies oriented nearly parallel to the surface. The damage occurs in a region below the charred material where material temperatures are relatively low - about 500 F. Wedge out occurs at the intersection of nozzle components whose plies are oriented at about 45 deg. The corner of the block of material breaks off along a ply interface. Pocketing erosion occurs in material with plies oriented normal to the surface. Thermal expansion is restrained in two directions resulting in large tensile strains and material failure normal to the surface. When a large section of material is removed as a result of damage, the insulation thickness is reduced which may lead to failure of the nozzle due to excessive heating of critical components. If these damage events cannot be prevented with certainty, the designer must increase the thickness of the insulator thus adding to both weight and cost. One of the difficulties in developing a full understanding of these macro damage mechanisms is that the loading environment and the material response to that environment are extremely complex. These types of damage are usually only observed in actual motor firings. Therefore, it is difficult and expensive to evaluate the reliability of new materials. Standard material tests which measure mechanical and thermal properties of test specimens can only provide a partial picture of how the material will respond in the service environment. The development of the ANALOG test procedure which can combine high heating rates and mechanical loads on a specimen will improve the understanding of the interactive effects of the various loads on the system. But a mechanistic model of material response which can account for the heterogeneity of the material, the progression of various micromechanical damage mechanisms, and the interaction of mechanical and thermal stresses on the material is required to accurately correlate material tests with response to service environments. A model based on fundamental damage mechanisms which is calibrated and verified under a variety of loading conditions will provide a general tool for predicting the response of rocket nozzles. The development of a micromechanical simulation technique was initiated and demonstrated to be effective for studying across-ply tensile failure of carbon/phenolic composites.

[Characteristics of the composition of Caucasian blackberry (Rubus caucasicus L.) leaves as a raw material for tea production].

PubMed

Melkadze, R G; Chichkovani, N Sh; Kakhniashvili, E Z

2008-01-01

The composition of Caucasian blackberry (Rubus caucasicus L.) six-leaf shoot was studied. The weight of the stem reached 50% of the total weight of the shoot. The content of moisture, extractive substances, and phenolic compounds was minimal at the beginning and end of the vegetation season. Phenolic compounds were represented by catechins, leukoanthocyanidins, and flavonols. The most abundant phenolic compounds in all parts of the blackberry shoot were leukoanthocyanidins, which accounted for approximately 50% of all compounds of this class. Phenolic compounds accumulated most actively in July and August. The average content of free amino acids in the blackberry leaf during the vegetation season was 26.68 mg/g. Among the total free amino acids, eleven have been identified, five of which proved to be essential (His, Arg, Met, Leu, Val) and accounted for 40% of the total amount of amino acids. The oxidability of acetone extract of the blackberry leaf was compared to the oxidability of total phenolic compounds and tea tannin. The tea product obtained from the blackberry leaf had good organoleptic parameters and a saturated extractive complex.

Statistical optimization of medium components and growth conditions by response surface methodology to enhance phenol degradation by Pseudomonas putida.

PubMed

Annadurai, Gurusamy; Ling, Lai Yi; Lee, Jiunn-Fwu

2008-02-28

In this work, a four-level Box-Behnken factorial design was employed combining with response surface methodology (RSM) to optimize the medium composition for the degradation of phenol by pseudomonas putida (ATCC 31800). A mathematical model was then developed to show the effect of each medium composition and their interactions on the biodegradation of phenol. Response surface method was using four levels like glucose, yeast extract, ammonium sulfate and sodium chloride, which also enabled the identification of significant effects of interactions for the batch studies. The biodegradation of phenol on Pseudomonas putida (ATCC 31800) was determined to be pH-dependent and the maximum degradation capacity of microorganism at 30 degrees C when the phenol concentration was 0.2 g/L and the pH of the solution was 7.0. Second order polynomial regression model was used for analysis of the experiment. Cubic and quadratic terms were incorporated into the regression model through variable selection procedures. The experimental values are in good agreement with predicted values and the correlation coefficient was found to be 0.9980.

Optimization of the ultrasound-assisted extraction of anthocyanins and total phenolic compounds in mulberry (Morus nigra) pulp.

PubMed

Espada-Bellido, Estrella; Ferreiro-González, Marta; Carrera, Ceferino; Palma, Miguel; Barroso, Carmelo G; Barbero, Gerardo F

2017-03-15

New ultrasound-assisted extraction methods for the determination of anthocyanins and total phenolic compounds present in mulberries have been developed. Several extraction variables, including methanol composition (50-100%), temperature (10-70°C), ultrasound amplitude (30-70%), cycle (0.2-0.7s), solvent pH (3-7) and solvent-solid ratio (10:1.5-20:1.5) were optimized. A Box-Behnken design in conjunction with a response surface methodology was employed to optimize the conditions for the maximum response based on 54 different experiments. Two response variables were considered: total anthocyanins and total phenolic compounds. Extraction temperature and solvent composition were found to be the most influential parameters for anthocyanins (48°C and 76%) and phenolic compounds (64°C and 61%). The developed methods showed high reproducibility and repeatability (RSD<5%). Finally, the new methods were successfully applied to real samples in order to investigate the presence of anthocyanins and total phenolic compounds in several mulberry jams. Copyright © 2016 Elsevier Ltd. All rights reserved.

Structure Properties and Mechanisms of Action of Naturally Originated Phenolic Acids and Their Derivatives against Human Viral Infections.

PubMed

Wu, Yi-Hang; Zhang, Bing-Yi; Qiu, Li-Peng; Guan, Rong-Fa; Ye, Zi-Hong; Yu, Xiao-Ping

2017-01-01

A great effort has been made to develop efficacious antiviral drugs, but many viral infections are still lack of efficient antiviral therapies so far. The related exploration of natural products to fight viruses has been raised in recent years. Natural compounds with structural diversity and complexity offer a great chance to find new antiviral agents. Particularly, phenolic acids have attracted considerable attention owing to their potent antiviral abilities and unique mechanisms. The aim of this review is to report new discoveries and updates pertaining to antiviral phenolic acids. The relevant references on natural phenolic acids were searched. The antiviral phenolic acids were classified according to their structural properties and antiviral types. Meanwhile, the antiviral characteristics and structure-activity relationships of phenolic acids and their derivatives were summarized. The review finds that natural phenolic acids and their derivatives possessed potent inhibitory effects on multiple virus in humans such as human immunodeficiency virus, hepatitis C virus, hepatitis B virus, herpes simplex virus, influenza virus and respiratory syncytial virus. In particular, caffeic acid/gallic acid and their derivatives exhibited outstanding antiviral properties by a variety of modes of action. Naturally derived phenolic acids especially caffeic acid/gallic acid and their derivatives may be regarded as novel promising antiviral leads or candidates. Additionally, scarcely any of these compounds has been used as antiviral treatment in clinical practice. Therefore, these phenolic acids with diverse skeletons and mechanisms provide us an excellent resource for finding novel antiviral drugs. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Variations of total phenol, carotenoid, in vitro antioxidant contents, and phenolic profiles of the pulp of five commercial varieties of mango

USDA-ARS?s Scientific Manuscript database

Mango (Mangifera indica L.) is a tropical fruit crop grown worldwide with widely attributed nutritional and health-promoting properties. Extensive studies have been made of the high concentrations of phenolic antioxidants in the peel, seeds, and leaves of mango, yet less is known about the phenolic ...

Phenolic profile and in vitro antioxidant capacity of insoluble dietary fiber powders from citrus (Citrus junos Sieb. ex Tanaka) pomace as affected by ultrafine grinding.

PubMed

Tao, Bingbing; Ye, Fayin; Li, Hang; Hu, Qiang; Xue, Shan; Zhao, Guohua

2014-07-23

The effects of mechanical and jet grindings on the proximate composition, phenolics, and antioxidant capacity of insoluble antioxidant dietary fiber powder from citrus pomace (IADFP-CP) were investigated in comparison with ordinary grinding. IADFP-CP from jet grinding showed higher levels of crude fat, total sugar, and free phenolics and lower levels of crude protein and bound phenolics than that from ordinary grinding. Totally, 14 phenolics (9 free, 1 bound, and 4 free/bound) in IADFP-CP were identified by RP-HPLC-DAD/ESI-Q-TOF-MS/MS. Hesperidin accounted for >57% of total phenolics in IADFP-CP. Among IADFP-CPs, the jet-ground presented the highest free phenolics but the lowest bound phenolics. The IADFP-CP from jet grinding presented the highest antioxidant capacity of free phenolics (by DPPH and FRAP assays), followed by the ones from mechanical and then ordinary grinding. The present study suggests that jet grinding could improve the extraction of phenolic compounds from IADFP-CP and increase the antioxidant capacities of free phenolics and the resultant powder.

Effects of seasonal olive mill wastewater applications on hydrological and biological soil properties in an olive orchard in Israel

NASA Astrophysics Data System (ADS)

Steinmetz, Zacharias; Kurtz, Markus; Peikert, Benjamin; Zipori, Isaac; Dag, Arnon; Schaumann, Gabriele E.

2014-05-01

During olive oil production in Mediterranean countries, large amounts of olive mill wastewater (OMW) are generated within a short period of time. OMW has a high nutrient content and could serve as fertilizer when applied on land. However, its fatty and phenolic constituents have adverse effects on hydrological and biological soil properties. It is still unknown how seasonal fluctuations in temperature and precipitation influence the fate and effect of OMW components on soil in a long-term perspective. An appropriate application season could mitigate negative consequences of OMW while preserving its beneficial effects. In order to investigate this, 14 L OMW m-2 were applied to different plots of an olive orchard in Gilat, Israel, in winter, spring, and summer, respectively. Hydrological soil properties (water drop penetration time, hydraulic conductivity, dynamic contact angle), physicochemical parameters (pH, EC, soluble ions, phenolic compounds, organic matter), and biological degradation (bait-lamina test) were measured to assess the soil state after OMW application. After one rainy season following OMW application, the soil quality of summer treatments significantly decreased compared to the control. This was particularly apparent in a ten-fold higher soil water repellency, a three-times lower biodegradation performance, and a four-fold higher content of phenolic compounds. 1.5 years after the last OMW application, the soil properties of winter treatments were comparable to the control, which suggests a certain recovery potential of the soil. Spring treatments resulted in an intermediate response compared to summer and winter treatments, but without any precipitation following OMW application. Strongest OMW effects were found in the top soil layers. Further research is needed to quantify the effect of spring treatments as well as to gain further insight into leaching effects, the composition of organic OMW constituents, and the kinetics of their degradation in relation to climatic conditions.

Foliar phenolic compounds of ten wild species of Verbenacea as antioxidants and specific chemomarkers.

PubMed

Ávila-Reyes, J A; Almaraz-Abarca, N; Chaidez-Ayala, A I; Ramírez-Noya, D; Delgado-Alvarado, E A; Torres-Ricario, R; Naranjo-Jiménez, N; Alanís-Bañuelos, R E

2018-02-01

The family Verbenaceae hosts important species used in traditional medicine of many countries. The taxonomic controversies concerning the specific delimitation of several of its species make it difficult to guarantee the botanical origin of herbal preparations based on species of this family. To contribute to the development of both specific chemomarkers and a quality control tool to authenticate the botanical origin of herbal preparations of Verbenacea species, we determined the foliar HPLC-DAD phenolic profiles and the antioxidant properties of 10 wild species of this family occurring in Mexico. The contents of phenols and flavonoids varied significantly among species. Priva mexicana showed the highest levels of total phenolics (53.4 mg g-1 dry tissue) and Verbena carolina had the highest levels of flavonoids (17.89 mg g-1 dry tissue). Relevant antioxidant properties revealed by antiradical and reducing power were found for the analyzed species. These properties varied significantly in a species-dependent manner. The phenolic compounds accumulated were flavones and phenolic acids. Flavones were the only type of flavonoids found. The results of a cluster analysis showed that the compounds were accumulated in species-specific profiles. The phenolic profiles are proposed as valuable chemomarkers that can become a useful tool for the quality control concerning the botanical origin of herbal medicinal preparations based on the species analyzed. In addition, phenolic profiles could contribute importantly to solve the taxonomic controversies concerning species delimitation in the family Verbenaceae.

Optimisation of Microwave-Assisted Extraction of Pomegranate (Punica granatum L.) Seed Oil and Evaluation 
of Its Physicochemical and Bioactive Properties.

PubMed

Çavdar, Hasene Keskin; Yanık, Derya Koçak; Gök, Uğur; Göğüş, Fahrettin

2017-03-01

Pomegranate seed oil was extracted in a closed-vessel high-pressure microwave system. The characteristics of the obtained oil, such as fatty acid composition, free fatty acidity, total phenolic content, antioxidant activity and colour, were compared to those of the oil obtained by cold solvent extraction. Response surface methodology was applied to optimise extraction conditions: power (176-300 W), time (5-20 min), particle size ( d =0.125-0.800 mm) and solvent to sample ratio (2:1, 6:1 and 10:1, by mass). The predicted highest extraction yield (35.19%) was obtained using microwave power of 220 W, particle size in the range of d =0.125-0.450 mm and solvent-to-sample ratio of 10:1 (by mass) in 5 min extraction time. Microwave-assisted solvent extraction (MASE) resulted in higher extraction yield than that of Soxhlet (34.70% in 8 h) or cold (17.50% in 8 h) extraction. The dominant fatty acid of pomegranate seed oil was punicic acid (86%) irrespective of the extraction method. Oil obtained by MASE had better physicochemical properties, total phenolic content and antioxidant activity than the oil obtained by cold solvent extraction.

Chemical and functional properties of the different by-products of artichoke (Cynara scolymus L.) from industrial canning processing.

PubMed

Ruiz-Cano, Domingo; Pérez-Llamas, Francisca; Frutos, María José; Arnao, Marino B; Espinosa, Cristóbal; López-Jiménez, José Ángel; Castillo, Julián; Zamora, Salvador

2014-10-01

In this study, the basic chemical composition and functional properties of six by-product fractions collected from different steps of artichoke industrial processing were evaluated. Fractions differed in thermal treatment, the bract position in the artichoke head and the cutting size. Contents of moisture, ash, protein, fat, dietary fibre, inulin, total phenolics, total flavonoids, caffeoyl derivatives and flavones were analysed. Antioxidant activity values were also determined. All assessed artichoke by-product fractions contained high-dietary fibre (53.6-67.0%) and low fat (2.5-3.7%). Artichoke by-product fractions contained high levels of inulin, especially in the boiled inner bracts (30%). Total phenolic and flavonoid contents and antioxidant activity (153-729 μmol gallic acid equivalents, 6.9-19.2 μmol quercetin equivalents and 85-234 μmol ascorbic acid equivalents per gram of dry matter, respectively) varied widely with the bract positions in the artichoke head and the thermal treatments. The more interesting fractions for use as functional ingredients were those situated closer to the artichoke heart and thermally treated. Copyright © 2014 Elsevier Ltd. All rights reserved.

Kainari, a Unique Greek Traditional Herbal Tea, from the Island of Lesvos: Chemical Analysis and Antioxidant and Antimicrobial Properties

PubMed Central

Bampali, Evangelia; Graikou, Konstantia; Aligiannis, Nektarios

2018-01-01

The chemical composition, as well as the total phenolic content (TPC) and the potential antioxidant and antimicrobial activity, of three Kainari-herbal tea samples from different areas of Lesvos Island (Greece) was evaluated. The rich aroma of the mixtures was studied through GC-MS, as well as through Headspace Solid-Phase Microextraction (HS-SPME)/GC-MS analyses. Cinnamon, clove, nutmeg, pepper, and ginger were identified as main ingredients, while, throughout the chemical analysis of the volatiles of one selected sample, several secondary metabolites have been isolated and identified on the basis of GC-MS as well as spectral evidence as eugenol, cinnamic aldehyde and myristicin, cinnamyl alcohol, alpha-terpinyl acetate, and β-caryophyllene. Furthermore, two food dyes, azorubine and amaranth, were also isolated and identified from the infusions. The total phenolic content was estimated and the free radical scavenging activity was determined by DPPH and ABTS assays and the antimicrobial activity of the extracts was tested showing a very interesting profile against all the assayed microorganisms. Due to its very pleasant aroma and taste properties as well as to its bioactivities, Kainari-herbal tea could be further proposed as functional beverage. PMID:29681979

Physico-chemical properties, antioxidant activity and mineral contents of pineapple genotypes grown in china.

PubMed

Lu, Xin-Hua; Sun, De-Quan; Wu, Qing-Song; Liu, Sheng-Hui; Sun, Guang-Ming

2014-06-23

The fruit physico-chemical properties, antioxidant activity and mineral contents of 26 pineapple [Ananas comosus (L.) Merr.] genotypes grown in China were measured. The results showed great quantitative differences in the composition of these pineapple genotypes. Sucrose was the dominant sugar in all 26 genotypes, while citric acid was the principal organic acid. Potassium, calcium and magnesium were the major mineral constituents. The ascorbic acid (AsA) content ranged from 5.08 to 33.57 mg/100 g fresh weight (FW), while the total phenolic (TP) content varied from 31.48 to 77.55 mg gallic acid equivalents (GAE)/100 g FW. The two parameters in the predominant cultivars Comte de Paris and Smooth Cayenne were relative low. However, MD-2 indicated the highest AsA and TP contents (33.57 mg/100 g and 77.55 mg GAE/100 g FM, respectively), and it also showed the strongest antioxidant capacity 22.85 and 17.30 μmol TE/g FW using DPPH and TEAC methods, respectively. The antioxidant capacity of pineapple was correlated with the contents of phenolics, flavonoids and AsA. The present study provided important information for the further application of those pineapple genotypes.

Compositional Changes in Foliage Phenolics with Plant Age, a Natural Experiment in Boreal Forests.

PubMed

Wam, Hilde Karine; Stolter, Caroline; Nybakken, Line

2017-09-01

The composition of plant secondary metabolites (PSMs) extensively impacts ecosystem functioning. It is vital that we understand temporal patterns in the plants' allocation of resources to PSMs, particularly those influenced by human activity. Existing data are insufficient in the long-term perspective of perennial plants (age or ontogeny). We analysed phenolic concentrations in foliage from birch (Betula pubescens Ehr.) considered to be undamaged and growing on 5, 10 and 15 years old clear-cuts in two boreal forest landscapes in Norway, sampled at the peak of the growing season. In sum, low molecular weight phenolic concentrations decreased with age. Apart from one apigenin glycoside, the low molecular weight phenolics co-varied similarly at all ages, suggesting a lack of temporal compound-specific prioritisation of this group. In contrast, the concentration of MeOH-soluble condensed tannins increased with age. The compositional shift fits well with several hypotheses that may provide proximate explanations for age patterns in PSM allocations, including both resource constraints and external pressures. Regardless of these explanations, our study adds an important perennial perspective (plant age) to temporal PSM patterns already well-known in boreal plant phenology (foliage age).

Argania spinosa var. mutica and var. apiculata: variation of fatty-acid composition, phenolic content, and antioxidant and α-amylase-inhibitory activities among varieties, organs, and development stages.

PubMed

El Adib, Saifeddine; Aissi, Oumayma; Charrouf, Zoubida; Ben Jeddi, Fayçal; Messaoud, Chokri

2015-09-01

Argania spinosa includes two varieties, var. apiculata and var. mutica. These argan varieties were introduced into Tunisia in ancient times and are actually cultivated in some botanic gardens. Little is known about the chemical differentiation among these argan varieties. Hence, the aim of this study was to determine the fatty-acid composition, the total phenolic and flavonoid contents, and the antioxidant and α-amylase-inhibitory activities of leaf, seed, and pulp extracts of both argan varieties harvested during the months of January to April. The fatty-acid distribution was found to depend on the argan variety, the plant organ, and the harvest time. Significant variations in the phenolic contents were observed between the investigated varieties as well as between leaves, pulps, and seeds of each variety. As expected, phenolic compounds were found to be contributors to the antioxidant and α-amylase-inhibitory activities of both argan varieties. The chemical differentiation observed among the two argan varieties, based mainly on the fatty-acid composition, might have some chemotaxonomic value. Copyright © 2015 Verlag Helvetica Chimica Acta AG, Zürich.

Amperometric Biosensor Based on Zirconium Oxide/Polyethylene Glycol/Tyrosinase Composite Film for the Detection of Phenolic Compounds

PubMed Central

Ahmad, Nor Monica; Abdullah, Jaafar; Yusof, Nor Azah; Ab Rashid, Ahmad Hazri; Abd Rahman, Samsulida; Hasan, Md. Rakibul

2016-01-01

A phenolic biosensor based on a zirconium oxide/polyethylene glycol/tyrosinase composite film for the detection of phenolic compounds has been explored. The formation of the composite film was expected via electrostatic interaction between hexacetyltrimethylammonium bromide (CTAB), polyethylene glycol (PEG), and zirconium oxide nanoparticles casted on screen printed carbon electrode (SPCE). Herein, the electrode was treated by casting hexacetyltrimethylammonium bromide on SPCE to promote a positively charged surface. Later, zirconium oxide was mixed with polyethylene glycol and the mixture was dropped cast onto the positively charged SPCE/CTAB. Tyrosinase was further immobilized onto the modified SPCE. Characterization of the prepared nanocomposite film and the modified SPCE surface was investigated by scanning electron microscopy (SEM), Electrochemical Impedance Spectroscopy (EIS), and Cyclic voltamogram (CV). The developed biosensor exhibits rapid response for less than 10 s. Two linear calibration curves towards phenol in the concentrations ranges of 0.075–10 µM and 10–55 µM with the detection limit of 0.034 µM were obtained. The biosensor shows high sensitivity and good storage stability for at least 30 days. PMID:27367738

Differences in composition of honey samples and their impact on the antimicrobial activities against drug multiresistant bacteria and pathogenic fungi.

PubMed

AL-Waili, Noori; Al Ghamdi, Ahmad; Ansari, Mohammad Javed; Al-Attal, Yehya; Al-Mubarak, Aarif; Salom, Khelod

2013-05-01

Antibiotic multiresistant microbes represent a challenging problem. Because honey has a potent antibacterial property, the antimicrobial effects of different honey samples against multiresistant pathogens and their compositions were investigated. Five honey samples were used: Talah, Dhahian, Sumra-1, Sidr, and Sumra-2. Samples were analyzed to determine chemical composition such as fructose, glucose, sucrose, pH, total flavonoids, total phenolics, hydrogen peroxide concentration, minerals and trace elements. Antimicrobial activities of the samples against 17 (16 were multiresistant) human pathogenic bacteria and three types of fungi were studied. Specimens of the isolates were cultured into 10 mL of 10-100% (volume/volume) honey diluted in broth. Microbial growth was assessed on a solid plate media after 24 h and 72 h incubation. The composition of honey samples varied considerably. Sumra 1 and 2 contained the highest level of flavonoids and phenolics and the lowest level of hydrogen peroxide, whereas Dhahian honey contained the highest level of hydrogen peroxide. Sixteen pathogens were antibiotic multiresistant. A single dose of each honey sample inhibited all the pathogens tested after 24 h and 72 h incubation. The most sensitive pathogens were Aspergillus nidulans, Salmonella typhimurum and Staphylococcus epidermidis (S. epidermidis). Although there was no statistically significant difference in the effectiveness of honey samples, the most effective honey against bacteria was Talah and against fungi were Dhahian and Sumra-2. Various honey samples collected from different geographical areas and plant origins showed almost similar antimicrobial activities against multiresistant pathogens despite considerable variation in their composition. Honey may represent an alternative candidate to be tested as part of management of drug multiresistant pathogens. Copyright © 2013 IMSS. Published by Elsevier Inc. All rights reserved.

Effect of roasting conditions on the composition and antioxidant properties of defatted walnut flour.

PubMed

Santos, Joana; Alvarez-Ortí, Manuel; Sena-Moreno, Estela; Rabadán, Adrián; Pardo, José E; Beatriz Pp Oliveira, M

2018-03-01

Walnut oil extraction by pressure systems produces a press cake as a by-product, with many of the beneficial walnut properties. The objective of this work was to evaluate the composition and antioxidant properties of walnut flours submitted to different roasting protocols (50, 100 and 150 °C during 30, 60 and 120 min). All walnut flours had about 42% protein and a significant amount of dietary fibre (17%), not being affected by the roasting process. Nonetheless, the fat content increased around 50% in walnuts flours subjected to longer and higher roasting temperatures (150 °C). The lipid fraction showed a good nutritional quality with a high vitamin E content (mainly γ-tocopherol) and fatty acid profile rich in linoleic and linolenic acids. The high phenolic content also provides great antioxidant capacity to the flours. Mild roasting of walnuts did not affect the quality of the flours that could be used as a functional ingredient in the food industry. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Chemical composition and bioactivity of different oregano (Origanum vulgare) extracts and essential oil.

PubMed

Teixeira, Bárbara; Marques, António; Ramos, Cristina; Serrano, Carmo; Matos, Olívia; Neng, Nuno R; Nogueira, José M F; Saraiva, Jorge Alexandre; Nunes, Maria Leonor

2013-08-30

There is a growing interest in industry to replace synthetic chemicals by natural products with bioactive properties. Aromatic plants are excellent sources of bioactive compounds that can be extracted using several processes. As far as oregano is concerned, studies are lacking addressing the effect of extraction processes in bioactivity of extracts. This study aimed to characterise the in vitro antioxidant and antibacterial properties of oregano (Origanum vulgare) essential oil and extracts (in hot and cold water, and ethanol), and the chemical composition of its essential oil. The major components of oregano essential oil were carvacrol, β-fenchyl alcohol, thymol, and γ-terpinene. Hot water extract had the strongest antioxidant properties and the highest phenolic content. All extracts were ineffective in inhibiting the growth of the seven tested bacteria. In contrast, the essential oil inhibited the growth of all bacteria, causing greater reductions on both Listeria strains (L. monocytogenes and L. innocua). O. vulgare extracts and essential oil from Portuguese origin are strong candidates to replace synthetic chemicals used by the industry. © 2013 Society of Chemical Industry.

Plant phenolics – from field to fork

USDA-ARS?s Scientific Manuscript database

Plant secondary metabolites, such as phenolics, are important to human health and for the organoleptic properties they impart to fresh and processed foods. Consumers judge appearance, taste, and texture when making purchasing decisions. Thorough identification of phenolic compounds is key to discern...

Principal component analysis of phenolic acid spectra

USDA-ARS?s Scientific Manuscript database

Phenolic acids are common plant metabolites that exhibit bioactive properties and have applications in functional food and animal feed formulations. The ultraviolet (UV) and infrared (IR) spectra of four closely related phenolic acid structures were evaluated by principal component analysis (PCA) to...

Soybean phenolic-rich extracts inhibit key-enzymes linked to type 2 diabetes (α-amylase and α-glucosidase) and hypertension (angiotensin I converting enzyme) in vitro.

PubMed

Ademiluyi, Adedayo O; Oboh, Ganiyu

2013-03-01

This study sought to assess the inhibitory activities of phenolic-rich extracts from soybean on α-amylase, α-glucosidase and angiotensin I converting enzyme (ACE) activities in vitro. The free phenolic extract of the soybean was obtained by extraction with 80% acetone, while that of the bound phenolic extract was done by extracting the alkaline and acid hydrolyzed residue with ethyl acetate. The inhibitory action of these extracts on the enzymes activity as well as their antioxidant properties was assessed. Both phenolic-rich extracts inhibited α-amylase, α-glucosidase and ACE enzyme activities in a dose dependent pattern. However, the bound phenolic extract exhibited significantly (P < 0.05) higher α-amylase and ACE inhibition while the free phenolic extract had significantly (P < 0.05) higher α-glucosidase inhibitory activity. Nevertheless, the free phenolic extract had higher α-glucosidase inhibitory activity when compared to that of α-amylase; this property confer an advantage on soybean phenolic-rich extracts over commercial antidiabetic drugs with little or no side effect. And inhibition of ACE suggests the antihypertension potential of soybean phenolic-rich extracts. Furthermore, the enzyme inhibitory activities of the phenolic-rich extracts were not associated with their phenolic content. Therefore, phenolic-rich extracts of soybean could inhibit key-enzyme linked to type 2 diabetes (α-amylase and α-glucosidase) and hypertension (ACE) and thus could explain in part the mechanism by which soybean renders these health promoting effect. Copyright © 2011 Elsevier GmbH. All rights reserved.

Novel Low-Density Ablators Containing Hyperbranched Poly(azomethine)s

NASA Technical Reports Server (NTRS)

Tigelaar, Dean

2011-01-01

An ablative composite is low-density (0.25 to 0.40 g/cu cm), easy to fabricate, and superior to the current state-of-the-art ablator (phenolic impregnated carbon ablator, PICA) in terms of decomposition temperature, char yield, and mechanical strength. Initial ablative testing with a CO2 laser under high-heat-flux (1,100 W/sq cm) conditions showed these new ablators are over twice as effective as PICA in terms of weight loss, as well as transfer of heat through the specimen. The carbon fiber/poly(azomethine) composites have the same density as PICA, but are 8 to 11 times stronger to irreversible breaking by tensile compression. In addition, polyazomethine char yields by thermogravimetric analysis are 70 to 80 percent at 1,000 C. This char yield is 10 to 20 percent higher than phenolic resins, as well as one of the highest char yields known for any polymer. A high char yield holds the composite together better toward shearing forces on reentry, as well as reradiates high heat fluxes. This innovative composite is stronger than PICA, so multiple pieces can be sealed together without fracture. Researchers have also studied polyazomethines before as linear polymers. Due to poor solubility, these polymers precipitate from the polymerization solvent as a low-molecular-weight (2 to 4 repeat units) powder. The only way found to date to keep linear polyazomethines in solution is by adding solubilizing side groups. However, these groups sacrifice certain polymer properties. These hyperbranched polyazomethines are high molecular weight and fully aromatic.

Fast Burn Booster Technology

DTIC Science & Technology

1992-05-21

phenolic resin. The warp/fill primary structure laminate plies are laid up next followed by the exit cone bias involute. The subassembly was vacuum bagged...CARBON FIBER/EPOXT 7075-T73 ALUMINUM 7kCo4x>€ axmjtuma* ROUNDING RING CARBON PHENOLIC INVOLUTE CARBON PHENOLIC LAMINATED INSULATION. MXSI-55...DESIGNS AND CURRENT STATUS *n ,.Wn„nd Composite Case. The older Sentry motor design employed a hybrid ( Kevlar -graphlte) fUament-wound ewe. *« S

Characterization of Substituted Phenol-Formaldehyde Resins Using Solid-State Carbon-13 NMR

DTIC Science & Technology

1989-05-22

synthesized from cashew nut shell liquid, 3-n-pentadecylphenol and phenol with formaldehyde. The resulting resins were crosslinked and then investigated using...should be sent SYNOPSIS Crosslinked substituted phenol-formaldehyde resins were synthesized from cashew nut shell liquid, 3-n-pentadecylphenol and... nut shell liquid (CNSL) and are the basis for binder resins and friction particles in composite friction materials. CNSL is isolated from cashew nut

Identification and Quantification of Flavonoids from Two Southern Italian Cultivars of Allium cepa L., Tropea (Red Onion) and Montoro (Copper Onion), and Their Capacity to Protect Human Erythrocytes from Oxidative Stress.

PubMed

Tedesco, Idolo; Carbone, Virginia; Spagnuolo, Carmela; Minasi, Paola; Russo, Gian Luigi

2015-06-03

Onions (Allium cepa) are consumed worldwide and represent an important source of dietary phytochemicals with proven antioxidant properties, such as phenolic acids, flavonoids, thiosulfinates, and anthocyanins. Epidemiological and experimental data suggest that regular consumption of onions is associated with a reduced risk of degenerative disorders. Therefore, it is of interest to investigate the biological properties of different varieties of onions. Here, we characterized for the first time a variety of onion, called Ramata di Montoro (coppery onion from Montoro), grown in a niche area in southern Italy, and compared its phenolic profile and antioxidant properties to a commercial ecotype of red onion, Tropea, also present in southern Italy. An analytical method based on high-performance liquid chromatography coupled with UV detection and mass spectrometry was used to separate and characterize the phenolic fraction (anthocyanins and flavonols) extracted from both coppery and red types. The main compounds detected in the two ecotypes were quercetin and quercetin glucosides, isorhamnetin glucosides, kaempferol glucoside, and, among anthocyanins, cyanidin glucosides. Tropea ecotype onion showed a higher content of flavonols (632.82 mg/kg fresh weight) than Montoro type onion (252.91 mg/kg fresh weight). Accordingly, the antioxidant activity of the former was 2.8-fold higher compared to the latter. More pronounced were the differences existing between the four anthocyanins detected in the two ecotypes, with those in the Tropea ecotype onion present at concentrations 20-230-fold higher than in the Montoro type onion. Both extracts reduced LDL oxidation about 6-fold and protected human erythrocytes from oxidative damage induced by HClO by about 40%. In addition, as a consequence of HClO treatment, glutathione concentration in erythrocytes was reduced about 50% and pretreatment with onion extracts induced a recovery of glutathione level by about 15-22%. Qualitative differences highlighted in the chemical composition of the two phenolic extracts, especially the total content of anthocyanins, which was 30-fold higher in Montoro type onion compared to Tropea ecotype, can be associated with the protective effects measured against oxidative damage induced in human erythrocytes.

Effects of fungal degradation on the CuO oxidation products of lignin: A controlled laboratory study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hedges, J.I.; Weliky, K.; Devol, A.H.

1988-11-01

Duplicate samples of birch wood were degraded for 0, 4, 8 and 12 weeks by the white-rot fungus, Phlebia tremellosus, and for 12 weeks by 6 other white-rot and brown-rot fungi. P. tremellosus caused progressive weight losses and increased the H/C and O/C of the remnant wood by preferentially degrading the lignin component of the middle lamellae. Total yields of syringyl phenols were decreased 1.5 times as fast as total vanillyl phenol yields. Within both phenol families, aldehyde precursors were degraded faster than precursors of the corresponding ketones, which were obtained in constant proportion to the total phenol yield. Althoughmore » two other white-rot fungi caused similar lignin compositional trends, a fourth white-rot species, Coriolus versicolor, simultaneously eroded all cell wall components and did not concentrate polysaccharides in the remnant wood. The brown-rot fungi also preferentially attacked syringyl structural units, but degraded all phenol precursors at a much slower rate than the white-rotters and did not produce excess vanillic acid. Degradation by P. tremellosus linearly increased the vanillic acid/vanillin ratio, (Ad/Al)v, of the remnant birch wood throughout the 12 week degradation study and exponentially decreased the absolute yields of total vanillyl phenols, total syringyl phenols and the syringyl/vanillyl phenol ratio, S/V. At the highest (Ad/Al)v of 0.50 total yields of syringyl and vanillyl phenols were decreased by 65% and 80%, respectively, with a resulting reduction of 40% in the original S/V. Many of the diagenetically related compositional trends that have been previously reported for lignins in natural environments can be explained by white-rot fungal degradation.« less

Shell thickness-dependent microwave absorption of core-shell Fe3O4@C composites.

PubMed

Du, Yunchen; Liu, Wenwen; Qiang, Rong; Wang, Ying; Han, Xijiang; Ma, Jun; Xu, Ping

2014-08-13

Core-shell composites, Fe3O4@C, with 500 nm Fe3O4 microspheres as cores have been successfully prepared through in situ polymerization of phenolic resin on the Fe3O4 surface and subsequent high-temperature carbonization. The thickness of carbon shell, from 20 to 70 nm, can be well controlled by modulating the weight ratio of resorcinol and Fe3O4 microspheres. Carbothermic reduction has not been triggered at present conditions, thus the crystalline phase and magnetic property of Fe3O4 micropsheres can be well preserved during the carbonization process. Although carbon shells display amorphous nature, Raman spectra reveal that the presence of Fe3O4 micropsheres can promote their graphitization degree to a certain extent. Coating Fe3O4 microspheres with carbon shells will not only increase the complex permittivity but also improve characteristic impedance, leading to multiple relaxation processes in these composites, thus the microwave absorption properties of these composites are greatly enhanced. Very interestingly, a critical thickness of carbon shells leads to an unusual dielectric behavior of the core-shell structure, which endows these composites with strong reflection loss, especially in the high frequency range. By considering good chemical homogeneity and microwave absorption, we believe the as-fabricated Fe3O4@C composites can be promising candidates as highly effective microwave absorbers.

Antioxidant Properties of Crude Extract, Partition Extract, and Fermented Medium of Dendrobium sabin Flower

PubMed Central

Abu, Farahziela; Mohd Akhir, Sobri

2017-01-01

Antioxidant properties of crude extract, partition extract, and fermented medium from Dendrobium sabin (DS) flower were investigated. The oven-dried DS flower was extracted using 100% methanol (w/v), 100% ethanol (w/v), and 100% water (w/v). The 100% methanolic crude extract showed the highest total phenolic content (40.33 ± mg GAE/g extract) and the best antioxidant properties as shown by DPPH, ABTS, and FRAP assays. A correlation relationship between antioxidant activity and total phenolic content showed that phenolic compounds were the dominant antioxidant components in this flower extract. The microbial fermentation on DS flower medium showed a potential in increasing the phenolic content and DPPH scavenging activity. The TPC of final fermented medium showed approximately 18% increment, while the DPPH of fermented medium increased significantly to approximately 80% at the end of the fermentation. Dendrobium sabin (DS) flower showed very good potential properties of antioxidant in crude extract and partition extract as well as better antioxidant activity in the flower fermented medium. PMID:28761496

Variations of total phenol, carotenoid, in vitro antioxidant contents, and phenolic profiles of the pulp of five commercial varieties of mango (Mangifera indica L.)

USDA-ARS?s Scientific Manuscript database

Mango (Mangifera indica L.) is a tropical fruit crop grown worldwide with widely attributed nutritional and health-promoting properties. Extensive studies have been made of the high concentrations of phenolic antioxidants in mango peel, seeds, and leaves, yet less is known about the phenolic antioxi...

Identification of phenolic acids and flavonoids in monofloral honey from Bangladesh by high performance liquid chromatography: determination of antioxidant capacity.

PubMed

Moniruzzaman, Mohammed; Yung An, Chua; Rao, Pasupuleti Visweswara; Hawlader, Mohammad Nurul Islam; Azlan, Siti Amirah Binti Mohd; Sulaiman, Siti Amrah; Gan, Siew Hua

2014-01-01

The aim of the present study was to characterize the phenolic acids, flavonoids, and antioxidant properties of monofloral honey collected from five different districts in Bangladesh. A new high performance liquid chromatography (HPLC) equipped with a UV detector method was developed for the identification of the phenolic acids and flavonoids. A total of five different phenolic acids were identified, with the most abundant being caffeic acid, benzoic acid, gallic acid, followed by chlorogenic acid and trans-cinnamic acid. The flavonoids, kaempferol, and catechin were most abundant, followed by myricetin and naringenin. The mean moisture content, total sugar content, and color characteristics of the honey samples were 18.36 ± 0.95%, 67.40 ± 5.63 g/100 g, and 129.27 ± 34.66 mm Pfund, respectively. The mean total phenolic acids, total flavonoid content, and proline content were 199.20 ± 135.23, 46.73 ± 34.16, and 556.40 ± 376.86 mg/kg, respectively, while the mean FRAP values and DPPH radical scavenging activity were 327.30 ± 231.87 μM Fe (II)/100 g and 36.95 ± 20.53%, respectively. Among the different types of honey, kalijira exhibited the highest phenolics and antioxidant properties. Overall, our study confirms that all the investigated honey samples are good sources of phenolic acids and flavonoids with good antioxidant properties.

Phenolic Molding Compounds

NASA Astrophysics Data System (ADS)

Koizumi, Koji; Charles, Ted; de Keyser, Hendrik

Phenolic Molding Compounds continue to exhibit well balanced properties such as heat resistance, chemical resistance, dimensional stability, and creep resistance. They are widely applied in electrical, appliance, small engine, commutator, and automotive applications. As the focus of the automotive industry is weight reduction for greater fuel efficiency, phenolic molding compounds become appealing alternatives to metals. Current market volumes and trends, formulation components and its impact on properties, and a review of common manufacturing methods are presented. Molding processes as well as unique advanced techniques such as high temperature molding, live sprue, and injection/compression technique provide additional benefits in improving the performance characterisitics of phenolic molding compounds. Of special interest are descriptions of some of the latest innovations in automotive components, such as the phenolic intake manifold and valve block for dual clutch transmissions. The chapter also characterizes the most recent developments in new materials, including long glass phenolic molding compounds and carbon fiber reinforced phenolic molding compounds exhibiting a 10-20-fold increase in Charpy impact strength when compared to short fiber filled materials. The role of fatigue testing and fatigue fracture behavior presents some insight into long-term reliability and durability of glass-filled phenolic molding compounds. A section on new technology outlines the important factors to consider in modeling phenolic parts by finite element analysis and flow simulation.

Evaluation of the chemical and nutritional characteristics of almonds (Prunus dulcis (Mill). D.A. Webb) as influenced by harvest time and cultivar.

PubMed

Summo, Carmine; Palasciano, Marino; De Angelis, Davide; Paradiso, Vito M; Caponio, Francesco; Pasqualone, Antonella

2018-04-30

Several authors studied the effect of harvest time on chemical and nutritional composition of almonds, but the results are partly conflicting, probably due to differences in the cultivars considered and to different agronomic and climatic conditions in the growing areas. In this paper the influence of harvest time and cultivar on the chemical and nutritional composition of almonds (Prunus dulcis (Mill). D.A. Webb) was evaluated. Ten cultivars were considered, grown in the same orchard and subjected to the same agronomical regime. Almonds were collected at two different harvest times: i) when the fruits were unripe, but already edible, and showed green and moist hull, and ii) when the fruits were ripe, with dry brown hull. The analyses of proximate composition, fatty acid profile, total phenolic compounds and antioxidant activity were carried out. Lipid content increased (p<0.001) during ripening, while both protein and carbohydrate content decreased (p<0.01). Fatty acid composition showed a not univocal behavior during ripening and was highly influenced by cultivar. Total phenolic compounds and antioxidant activity varied among cultivars but increased during ripening with the exception of Marcona cv. Genco and Francolì cvs were found to be phenolic-rich cultivars. Harvest time and cultivars significantly influenced the chemical and nutritional composition of almonds. Genotype strongly influenced fatty acid composition and total phenolic compounds. The changes of bioactive compounds and antioxidant activity suggest that the synthesis of antioxidants occur also in the last stage of ripening. Unripe almonds, a valuable niche product, showed interesting nutritional value. This article is protected by copyright. All rights reserved.

Spectroscopic analysis of phenolic compounds for food and feed formulations

USDA-ARS?s Scientific Manuscript database

Phenolic compounds exhibit several bioactive properties including anti-oxidant, anti-microbial, and anti-fungal characteristics with potential applications as additives in functional food and feed formulations. Phenolic compounds occur in plants as secondary metabolites and may be recovered as a co-...

Response Surface Methodology Optimization of Ultrasonic-Assisted Extraction of Acer Truncatum Leaves for Maximal Phenolic Yield and Antioxidant Activity.

PubMed

Yang, Lingguang; Yin, Peipei; Fan, Hang; Xue, Qiang; Li, Ke; Li, Xiang; Sun, Liwei; Liu, Yujun

2017-02-04

This study is the first to report the use of response surface methodology to improve phenolic yield and antioxidant activity of Acer truncatum leaves extracts (ATLs) obtained by ultrasonic-assisted extraction. The phenolic composition in ATLs extracted under the optimized conditions were characterized by UPLC-QTOF-MS/MS. Solvent and extraction time were selected based on preliminary experiments, and a four-factors-three-levels central composite design was conducted to optimize solvent concentration ( X ₁), material-to-liquid ratio ( X ₂), ultrasonic temperature ( X ₃) and power ( X ₄) for an optimal total phenol yield ( Y ₁) and DPPH• antioxidant activity ( Y ₂). The results showed that the optimal combination was ethanol:water ( v : v ) 66.21%, material-to-liquid ratio 1:15.31 g/mL, ultrasonic bath temperature 60 °C, power 267.30 W, and time 30 min with three extractions, giving a maximal total phenol yield of 7593.62 mg gallic acid equivalent/100 g d.w. and a maximal DPPH• antioxidant activity of 74,241.61 μmol Trolox equivalent/100 g d.w. Furthermore, 22 phenolics were first identified in ATL extract obtained under the optimized conditions, indicating that gallates, gallotannins, quercetin, myricetin and chlorogenic acid derivatives were the main phenolic components in ATL. What's more, a gallotannins pathway existing in ATL from gallic acid to penta- O -galloylglucoside was proposed. All these results provide practical information aiming at full utilization of phenolics in ATL, together with fundamental knowledge for further research.

Soymilk enriched with green coffee phenolics - Antioxidant and nutritional properties in the light of phenolics-food matrix interactions.

PubMed

Sęczyk, Łukasz; Świeca, Michał; Gawlik-Dziki, Urszula

2017-05-15

This study investigated the effect of soymilk fortification with green coffee extract (GCE) on phenolic contents, antioxidant capacity, relative in vitro digestibility of proteins and starch, and consumer acceptance. Special attention was paid to the effect of phenolics-food matrix interactions on fortification efficiency. Soymilk was enriched with GCE extracts containing 0.025-1mg of phenolics per 1mL-samples M1-M6. Compared to control, an increase in phenolic contents of up to 70% (M6) was observed for potentially bioaccessible fractions (AD). The antiradical activity and reducing power were also about 1.9 and 10.1 times higher, respectively. However, the determined phenolic and antioxidant activities differed from those predicted. Fortification improved the digestibility of nutrients when higher doses of GCE was introduced (M4-M6). The addition of GCE at an adequate dose allowed the production of a beverage with elevated hedonic properties. In conclusion, fortification was a successful in improving the pro-health status of soymilk. Copyright © 2016 Elsevier Ltd. All rights reserved.

Transition of phenolics and cyanogenic glycosides from apricot and cherry fruit kernels into liqueur.

PubMed

Senica, Mateja; Stampar, Franci; Veberic, Robert; Mikulic-Petkovsek, Maja

2016-07-15

Popular liqueurs made from apricot/cherry pits were evaluated in terms of their phenolic composition and occurrence of cyanogenic glycosides (CGG). Analyses consisted of detailed phenolic and cyanogenic profiles of cherry and apricot seeds as well as beverages prepared from crushed kernels. Phenolic groups and cyanogenic glycosides were analyzed with the aid of high-performance liquid chromatography (HPLC) and mass spectrophotometry (MS). Lower levels of cyanogenic glycosides and phenolics have been quantified in liqueurs compared to fruit kernels. During fruit pits steeping in the alcohol, the phenolics/cyanogenic glycosides ratio increased and at the end of beverage manufacturing process higher levels of total analyzed phenolics were detected compared to cyanogenic glycosides (apricot liqueur: 38.79 μg CGG per ml and 50.57 μg phenolics per ml; cherry liqueur 16.08 μg CGG per ml and 27.73 μg phenolics per ml). Although higher levels of phenolics are characteristic for liqueurs made from apricot and cherry pits these beverages nevertheless contain considerable amounts of cyanogenic glycosides. Copyright © 2016 Elsevier Ltd. All rights reserved.

Evaluation of Antiradical Activity of Different Cocoa and Chocolate Products: Relation with Lipid and Protein Composition

PubMed Central

Vertuani, Silvia; Scalambra, Emanuela; Vittorio, Trotta; Bino, Alessia; Malisardi, Gemma; Baldisserotto, Anna

2014-01-01

Abstract Chocolate antioxidant properties are often claimed; however, they are frequently different from the parent natural sources due to the industry or artisan transformation. In particular, antioxidant property of chocolate and cocoa are not adequately taken into consideration by consumers who normally make use of this food just for its flavor and taste properties. In this study, we have investigated the antioxidant capacity and total phenolic content of cocoa nibs, cocoa masses, and corresponding chocolate bars with different percentages of cocoa from different origins. The antioxidant capacity of the different samples was measured by two different assays [1,1-diphenyl-2-picryl-hydrazyl radical (DPPH) and ferric reducing antioxidant of potency (FRAP) tests]. The Folin–Ciocalteu reagent was used to assess the total phenolic content. The masses showed a higher antioxidant power than the nibs, and this has been attributed to the fact that in the nibs is still present the lipid part, which will form the cocoa butter. The influence of milk, whey, and soy proteins was also investigated. Our results showed that the extra dark cocoa bar, 100% cocoa chocolate, is the best in terms of total polyphenol content and in terms of antioxidant capacity according to the DPPH and FRAP tests. In addition, the bars of organic dark chocolate 80%, dark Tanzania 80%, and Trinidad 80% products are well performing in all respects. As highlighted by us, the antiradical properties of cocoa products are higher than many antioxidant supplements in tablets. PMID:24433077

Evaluation of antiradical activity of different cocoa and chocolate products: relation with lipid and protein composition.

PubMed

Vertuani, Silvia; Scalambra, Emanuela; Vittorio, Trotta; Bino, Alessia; Malisardi, Gemma; Baldisserotto, Anna; Manfredini, Stefano

2014-04-01

Chocolate antioxidant properties are often claimed; however, they are frequently different from the parent natural sources due to the industry or artisan transformation. In particular, antioxidant property of chocolate and cocoa are not adequately taken into consideration by consumers who normally make use of this food just for its flavor and taste properties. In this study, we have investigated the antioxidant capacity and total phenolic content of cocoa nibs, cocoa masses, and corresponding chocolate bars with different percentages of cocoa from different origins. The antioxidant capacity of the different samples was measured by two different assays [1,1-diphenyl-2-picryl-hydrazyl radical (DPPH) and ferric reducing antioxidant of potency (FRAP) tests]. The Folin-Ciocalteu reagent was used to assess the total phenolic content. The masses showed a higher antioxidant power than the nibs, and this has been attributed to the fact that in the nibs is still present the lipid part, which will form the cocoa butter. The influence of milk, whey, and soy proteins was also investigated. Our results showed that the extra dark cocoa bar, 100% cocoa chocolate, is the best in terms of total polyphenol content and in terms of antioxidant capacity according to the DPPH and FRAP tests. In addition, the bars of organic dark chocolate 80%, dark Tanzania 80%, and Trinidad 80% products are well performing in all respects. As highlighted by us, the antiradical properties of cocoa products are higher than many antioxidant supplements in tablets.

Proximate composition, total phenolic content, and antioxidant activity of seagrape (Caulerpa lentillifera).

PubMed

Nguyen, Van Tang; Ueng, Jinn-Pyng; Tsai, Guo-Jane

2011-09-01

The proximate composition of seagrape (Caulerpa lentillifera) from culture ponds in Penghu, Taiwan was analyzed. The phenolic content and the antioxidant activities including the 1,1-diphenyl-2-picryl-hydrazil (DPPH) radical scavenging activity, ferric ion-reducing activity, hydrogen peroxide scavenging activity, and ferrous ion chelating (FIC) activity of the ethanolic extracts of dry seagrape samples using 2 drying methods of freeze drying and thermal drying were compared with the ethanolic extract of Oolong tea as a reference. The contents (dry weight basis) of carbohydrate, crude protein, crude lipid, crude fiber, and ash of seagrape obtained from culture ponds in Taiwan were 64.00%, 9.26%, 1.57%, 2.97%, and 22.20%, respectively. The total phenolic content (1.30 mg gallic acid equivalent [GAE]/g dry weight) of the ethanolic extract of thermally dried seagrape was significantly lower (P < 0.05) than that (2.04 mg GAE/g dry weight) of freeze-dried seagrape, and both were significantly lower than that (13.58 mg GAE/g dry weight) of Oolong tea. At the same phenolic content, the antioxidant activities of freeze-dried seagrape were significantly higher (P < 0.05) than those of thermally dried seagrape. Compared with Oolong tea, seagrape, irrespective of drying method used, generally had strong hydrogen peroxide scavenging activity; but it was weak in DPPH radical scavenging activity, ferric ion-reducing activity, and FIC activity. The antioxidant activity of seagrape and Oolong tea was significantly influenced by their phenolic contents. The proximate composition, total phenolic content, and antioxidant activity of seagrape (Caulerpa lentillifera) in Taiwan were determined in this research to indicate nutritionally of this edible seaweed to human health, and compared these results to previous studies. © 2011 Institute of Food Technologists®

Phenol oxidase activity in secondary transformed peat-moorsh soils

NASA Astrophysics Data System (ADS)

Styła, K.; Szajdak, L.

2009-04-01

The chemical composition of peat depends on the geobotanical conditions of its formation and on the depth of sampling. The evolution of hydrogenic peat soils is closely related to the genesis of peat and to the changes in water conditions. Due to a number of factors including oscillation of ground water level, different redox potential, changes of aerobic conditions, different plant communities, and root exudes, and products of the degradation of plant remains, peat-moorsh soils may undergo a process of secondary transformation conditions (Sokolowska et al. 2005; Szajdak et al. 2007). Phenol oxidase is one of the few enzymes able to degrade recalcitrant phenolic materials as lignin (Freeman et al. 2004). Phenol oxidase enzymes catalyze polyphenol oxidation in the presence of oxygen (O2) by removing phenolic hydrogen or hydrogenes to from radicals or quinines. These products undergo nucleophilic addition reactions in the presence or absence of free - NH2 group with the eventual production of humic acid-like polymers. The presence of phenol oxidase in soil environments is important in the formation of humic substances a desirable process because the carbon is stored in a stable form (Matocha et al. 2004). The investigations were carried out on the transect of peatland 4.5 km long, located in the Agroecological Landscape Park host D. Chlapowski in Turew (40 km South-West of Poznań, West Polish Lowland). The sites of investigation were located along Wyskoć ditch. The following material was taken from four chosen sites marked as Zbechy, Bridge, Shelterbelt and Hirudo in two layers: cartel (0-50cm) and cattle (50-100cm). The object of this study was to characterize the biochemical properties by the determination of the phenol oxidize activity in two layers of the four different peat-moors soils used as meadow. The phenol oxidase activity was determined spectrophotometrically by measuring quinone formation at λmax=525 nm with catechol as substrate by method of Perucci et al. (2000). In peat the highest activities of phenol oxidase was observed in the combinations marked as Shelterbelt and whereas the lowest - in Zbechy, Bridge and Hirudo. Activities of this enzyme in peat ranged from 15.35 to 38.33 μmol h-1g d.m soil. Increased activities of phenol oxidase have been recorded on the depth 50-100cm - catotelm (21.74-38.33 μmol h-1g d.m soil) in comparison with the depth 0-50cm - acrotelm (15.35-28.32 μmol h-1g d.m soil). References Freeman, C., Ostle N.J., Fener, N., Kang H. 2004. A regulatory role for phenol oxidase during decomposition in peatlands. Soil Biology and Biochemistry, 36, 1663-1667. Matocha Ch.J., Haszler G.R., Grove J.H. 2004. Nitrogen fertilization suppresses soil phenol oxidase enzyme activity in no-tillage systems. Soil Science, 169/10, 708-714. Perucci P., Casucci C., Dumontet S. 2000. An improved method to evaluate the o-diphenol oxidase activity of soil. Soil Biology and Biochemistry, 32, 1927-1933. Sokolowska Z., Szajdak L., Matyka-Sarzyńska D. 2005. Impact of the degree of secondary transformation on amid-base properties of organic compounds in mucks. Geoderma, 127, 80-90. Szajdak L., Szczepański M., Bogacz A. 2007. Impact of secondary transformation of peat-moorsh soils on the decrease of nitrogen and carbon compounds in ground water. Agronomy Research, 5/2, 189-200.

Ballistic Performance of Alimina/S-2 Glass-Reinforced Polymer-Matrix Composite Hybrid Lightweight Armor Against Armor Piercing (AP) and Non-AP Projectiles

DTIC Science & Technology

2007-01-01

and a phenolic -resin based polymeric matrix. Such armor panels offer superior protection against fragmented ballistic threats when compared to...database does not contain a material model for the HJ1 composite but provides a model for a Kevlar Fiber Reinforced Polymer (KFRP) containing 53 vol... phenolic resin and epoxy yield stresses and then with a ratio of the S-2 glass and aramid fibers volume fractions. To test the validity of the

Fabrication and physical testing of graphite composite panels utilizing woven graphite fabric with current and advanced state-of-the-art resin systems

NASA Technical Reports Server (NTRS)

Lee, S. C. S.

1979-01-01

Three weaves were evaluated; a balanced plain weave, a balanced 8-harness satin weave, and a semiunidirectional crowfoot satin weave. The current state-of-the-art resin system selected was Fiberite's 934 Epoxy; the advanced resin systems evaluated were Phenolic, Phenolic/Novolac, Benzyl and Bismaleimide. The panels were fabricated for testing on NASA/Ames Research Center's Composites Modification Program. Room temperature mechanical tests only were performed by Hitco; the results are presented.

[Study on chemical compositions and crystallinity changes of bamboo treated with gamma rays].

PubMed

Sun, Feng-Bo; Jiang, Ze-hui; Fei, Ben-hua; Lu, Fang; Yu, Zi-xuan; Chang, Xiang-zhen

2011-07-01

The structures and qualities of main chemical compositions in cell wall of bamboo treated with gamma rays were tested by nuclear magnetic resonance spectrometer (NMR) and X-ray Diffraction (XRD). The result indicated that the bamboo crystallinity increased at the beginning of irradiation process, while the crystallinity reduced when the irradiation dose was raised to about 100 kGy. During the whole irradiation process, hemicellulose degraded, and with the irradiation doses increased the non-phenolic lignin changed to the phenolic.

Effect of Nitrogen Fertilization and Harvest Time on Steviol Glycosides, Flavonoid Composition, and Antioxidant Properties in Stevia rebaudiana Bertoni.

PubMed

Tavarini, Silvia; Sgherri, Cristina; Ranieri, Anna Maria; Angelini, Luciana G

2015-08-12

This work investigated the effect of nitrogen fertilization and harvest time on the flavonoid composition and antioxidant properties of Stevia rebaudiana leaves. At the same time, changes in stevioside (Stev) and rebaudioside A (RebA) contents were recorded. A pot trial under open air conditions was set up, testing five N rates and three harvest times. The results showed that, by using an adequate N rate and choosing an appropriate harvest time, it was possible to significantly increase and optimize the bioactive compound levels. In particular, higher RebA, RebA/Stev ratio, total phenols and flavonoids, luteolin-7-O-glucoside, and apigenin-7-O-glucoside levels and antioxidant capacity were recorded by supplying 150 kg N ha(-1). Reduced or increased N availability in comparison with N150 had no consistent effect on Stevia phytochemicals content. Significant correlations were also found between stevioside and some of the flavonoids, indicating a possible role of flavonoids in the stevioside metabolic pathway, which deserves more investigations.

Influence of jet milling and particle size on the composition, physicochemical and mechanical properties of barley and rye flours.

PubMed

Drakos, Antonios; Kyriakakis, Georgios; Evageliou, Vasiliki; Protonotariou, Styliani; Mandala, Ioanna; Ritzoulis, Christos

2017-01-15

Finer barley and rye flours were produced by jet milling at two feed rates. The effect of reduced particle size on composition and several physicochemical and mechanical properties of all flours were evaluated. Moisture content decreased as the size of the granules decreased. Differences on ash and protein contents were observed. Jet milling increased the amount of damaged starch in both rye and barley flours. True density increased with decreased particle size whereas porosity and bulk density increased. The solvent retention capacity profile was also affected by jet milling. Barley was richer in phenolics and had greater antioxidant activity than rye. Regarding colour, both rye and barley flours when subjected to jet milling became brighter, whereas their yellowness was not altered significantly. The minimum gelation concentration for all flours was 16%w/v. Barley flour gels were stronger, firmer and more elastic than the rye ones. Copyright © 2016 Elsevier Ltd. All rights reserved.

Berry Leaves: An Alternative Source of Bioactive Natural Products of Nutritional and Medicinal Value.

PubMed

Ferlemi, Anastasia-Varvara; Lamari, Fotini N

2016-06-01

Berry fruits are recognized, worldwide, as "superfoods" due to the high content of bioactive natural products and the health benefits deriving from their consumption. Berry leaves are byproducts of berry cultivation; their traditional therapeutic use against several diseases, such as the common cold, inflammation, diabetes, and ocular dysfunction, has been almost forgotten nowadays. Nevertheless, the scientific interest regarding the leaf composition and beneficial properties grows, documenting that berry leaves may be considered an alternative source of bioactives. The main bioactive compounds in berry leaves are similar as in berry fruits, i.e., phenolic acids and esters, flavonols, anthocyanins, and procyanidins. The leaves are one of the richest sources of chlorogenic acid. In various studies, these secondary metabolites have demonstrated antioxidant, anti-inflammatory, cardioprotective, and neuroprotective properties. This review focuses on the phytochemical composition of the leaves of the commonest berry species, i.e., blackcurrant, blackberry, raspberry, bilberry, blueberry, cranberry, and lingonberry leaves, and presents their traditional medicinal uses and their biological activities in vitro and in vivo.

Composition, physicochemical properties and thermal inactivation kinetics of polyphenol oxidase and peroxidase from coconut (Cocos nucifera) water obtained from immature, mature and overly-mature coconut.

PubMed

Tan, Thuan-Chew; Cheng, Lai-Hoong; Bhat, Rajeev; Rusul, Gulam; Easa, Azhar Mat

2014-01-01

Composition, physicochemical properties and enzyme inactivation kinetics of coconut water were compared between immature (IMC), mature (MC) and overly-mature coconuts (OMC). Among the samples studied, pH, turbidity and mineral contents for OMC water was the highest, whereas water volume, titratable acidity, total soluble solids and total phenolics content for OMC water were the lowest. Maturity was found to affect sugar contents. Sucrose content was found to increase with maturity, and the reverse trend was observed for fructose and glucose. Enzyme activity assessment showed that polyphenol oxidase (PPO) in all samples was more heat resistant than peroxidase (POD). Compared to IMC and MC, PPO and POD from OMC water showed the lowest thermal resistance, with D83.3°C=243.9s (z=27.9°C), and D83.3°C=129.9s (z=19.5°C), respectively. Copyright © 2013 Elsevier Ltd. All rights reserved.

Optimization of ultrasound-assisted hydroalcoholic extraction of phenolic compounds from walnut leaves using response surface methodology.

PubMed

Nour, Violeta; Trandafir, Ion; Cosmulescu, Sina

2016-10-01

Context Walnut leaves are highly appreciated for their pharmacological effects and therapeutic properties which are mainly attributed to their high content of phenolic compounds. Objective This study optimizes ultrasound assisted hydroalcoholic extraction (UAE) of phenolic compounds from dried walnut leaves by the maximization of total phenolics content (TPC) and total flavanoids content (TFC) of the extracts. Materials and methods Optimal conditions with regard to ethanol concentration (X1: 12.17-95.83% v/v), extraction time (X2: 8.17-91.83 min) and liquid-to-solid ratio (X3: 4.96-25.04 v/w) were identified using central composite design combined with response surface methodology. A high-performance liquid chromatography method with diode-array detection was used to quantify phenolic acids (gallic, vanillic, chlorogenic, caffeic, syringic, p-coumaric, ferulic, sinapic, salicylic, ellagic and trans-cinnamic), flavonoids (catechin, epicatechin, rutin, myricetin and quercetin) and juglone in the extracts. Results Liquid-to-solid ratio and ethanol concentration proved to be the primary factors affecting the extraction efficiency. The maximum predicted TPC, under the optimized conditions (61% ethanol concentration, 51.28 min extraction time and 4.96 v/w liquid-to-solid ratio) was 10125.4 mg gallic acid equivalents per liter while maximum TFC (2925 mg quercetin equivalents per liter) occurred at 67.83% ethanol concentration, 4.96 v/w liquid-to-solid ratio and 49.37 min extraction time. High significant correlations were found between antioxidant activity and both TPC (R(2 )=( )0.81) and TFC (R(2 )=( )0.78). Discussion and conclusion Extracts very rich in polyphenols could be obtained from walnut leaves by using UAE, aimed at preparing dietary supplements, nutraceuticals or functional food ingredients.

Phenol degradation catalyzed by a peroxidase mimic constructed through the grafting of heme onto metal-organic frameworks.

PubMed

Jiang, Wei; Yang, Jiebing; Wang, Xinghuo; Han, Haobo; Yang, Yan; Tang, Jun; Li, Quanshun

2018-01-01

The aim of this work was to construct a peroxidase mimic for achieving the phenol degradation through Fenton reaction. The enzyme mimic was synthesized through the conjugation of heme with the amino group of 2-amino-1,4-benzene dicarboxylate in UiO-66-NH 2 (ZrMOF), namely Heme-ZrMOF. Compared to free heme, the composite Heme-ZrMOF exhibited an obviously enhanced ability for phenol degradation with up to 97.3% of phenol removal after 2h. Meanwhile, it could achieve the easy separation of catalyst from the system and the elimination of iron residues in the process of phenol degradation. Finally, the catalyst Heme-ZrMOF was observed to possess good recyclability in the phenol degradation with still 76.2% of phenol removal after 4 cycles. Copyright © 2017 Elsevier Ltd. All rights reserved.

[Effect of phenolic ketones on ethanol fermentation and cellular lipid composition of Pichia stipitis].

PubMed

Yang, Jinlong; Cheng, Yichao; Zhu, Yuanyuan; Zhu, Junjun; Chen, Tingting; Xu, Yong; Yong, Qiang; Yu, Shiyuan

2016-02-01

Lignin degradation products are toxic to microorganisms, which is one of the bottlenecks for fuel ethanol production. We studied the effects of phenolic ketones (4-hydroxyacetophenone, 4-hydroxy-3-methoxy-acetophenone and 4-hydroxy-3,5-dimethoxy-acetophenone) derived from lignin degradation on ethanol fermentation of xylose and cellular lipid composition of Pichia stipitis NLP31. Ethanol and the cellular fatty acid of yeast were analyzed by high performance liquid chromatography (HPLC) and gas chromatography/mass spectrometry (GC/MS). Results indicate that phenolic ketones negatively affected ethanol fermentation of yeast and the lower molecular weight phenolic ketone compound was more toxic. When the concentration of 4-hydroxyacetophenone was 1.5 g/L, at fermentation of 24 h, the xylose utilization ratio, ethanol yield and ethanol concentration decreased by 42.47%, 5.30% and 9.76 g/L, respectively, compared to the control. When phenolic ketones were in the medium, the ratio of unsaturated fatty acids to saturated fatty acids (UFA/SFA) of yeast cells was improved. When 1.5 g/L of three aforementioned phenolic ketones was added to the fermentation medium, the UFA/SFA ratio of yeast cells increased to 3.03, 3.06 and 3.61, respectively, compared to 2.58 of the control, which increased cell membrane fluidity and instability. Therefore, phenolic ketones can reduce the yeast growth, increase the UFA/SFA ratio of yeast and lower ethanol productivity. Effectively reduce or remove the content of lignin degradation products is the key to improve lignocellulose biorefinery.

The effect of drying temperatures on antioxidant activity, phenolic compounds, fatty acid composition and tocopherol contents in citrus seed and oils.

PubMed

Al Juhaimi, Fahad; Özcan, Mehmet Musa; Uslu, Nurhan; Ghafoor, Kashif

2018-01-01

In this study, the effect of drying temperature on antioxidant activity, phenolic compounds, fatty acid composition and tocopherol content of citrus seeds and oils were studied. Kinnow mandarin seed, dried at 60 °C, exhibited the highest antioxidant activity. Orlendo orange seed had the maximum total phenolic content and α-tocopherol content, with a value of 63.349 mg/100 g and 28.085 mg/g (control samples), respectively. The antioxidant activity of Orlendo orange seed (63.349%) was higher than seeds of Eureka lemon (55.819%) and Kinnow mandarin (28.015%), while the highest total phenolic content was found in seeds of Kinnow mandarin, followed by Orlendo orange and Eureka lemon (113.132). 1.2-Dihydroxybenzene (13.171), kaempferol (10.780), (+)-catechin (9.341) and isorhamnetin (7.592) in mg/100 g were the major phenolic compounds found in Kinnow mandarin. Among the unsaturated fatty acids, linoleic acid was the most abundant acid in all oils, which varied from 44.4% (dried at 80 °C) to 46.1% (dried at 70 °C), from 39.0% (dried at 60 °C) to 40.0% (dried at 70 °C). The total phenolic content, antioxidant activity and phenolic compounds of citrus seeds and tocopherol content of seed oils were significantly affected by drying process and varied depending on the drying temperature.

Evaluation of the anthocyanin release and health-promoting properties of Pinot Noir grape juices after pulsed electric fields.

PubMed

Leong, Sze Ying; Burritt, David John; Oey, Indrawati

2016-04-01

This study evaluated the health-promoting properties of Pinot Noir juices (Vitis vinifera L.) obtained at different maceration times after pulsed electric fields (PEF) using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and human intestinal Caco-2 cells assays. Juice quality, anthocyanins, total phenolics and vitamin C were also determined. The evaluation of bioprotective capacity of the juice against H2O2-induced oxidative stress in Caco-2 cells was determined using biomarkers for cellular health and integrity: cell viability and lactate dehydrogenase (LDH) leakage. Compared to untreated grape juice, PEF pre-treatment on grapes enhanced the release of the major anthocyanin found in Pinot Noir, i.e. malvidin-3-O-glucoside (+224%). Increase in the content of total phenolic (+61%) and vitamin C (+19%) as well as improvement in the DPPH scavenging activity (+31%) and bioprotective capacity (+25% for cell viability and +30% for LDH leakage) were observed in grape juices following PEF treatment. Bioprotective capacity determined by the cellular biomarkers had significant linear correlations with malvidin-3-O-glucoside content (0.71⩽r⩽0.73) whereas DPPH scavenging activity was not well correlated with malvidin-3-O-glucoside (r=0.30) and total phenolics (r=0.30). Therefore, evaluation of the bioprotective capacities using Caco-2 cell assay performed in this study makes a novel contribution to the current knowledge that demonstrates the capability of PEF technology to produce plant-based foods with better phytochemical composition and exhibiting the capacity to protect cells from oxidative stress. Copyright © 2015 Elsevier Ltd. All rights reserved.

Aerogel and xerogel composites for use as carbon anodes

DOEpatents

Cooper, John F.; Tillotson, Thomas M.; Hrubesh, Lawrence W.

2010-10-12

A method for forming a reinforced rigid anode monolith and fuel and product of such method. The method includes providing a solution of organic aerogel or xerogel precursors including at least one of a phenolic resin, phenol (hydroxybenzene), resorcinol(1,3-dihydroxybenzene), or catechol(1,2-dihydroxybenzene); at least one aldehyde compound selected from the group consisting of formaldehyde, acetaldehyde, and furfuraldehyde; and an alkali carbonate or phosphoric acid catalyst; adding internal reinforcement materials comprising carbon to said precursor solution to form a precursor mixture; gelling said precursor mixture to form a composite gel; drying said composite gel; and pyrolyzing said composite gel to form a wettable aerogel/carbon composite or a wettable xerogel/carbon composite, wherein said composites comprise chars and said internal reinforcement materials, and wherein said composite is suitable for use as an anode with the chars being fuel capable of being combusted in a molten salt electrochemical fuel cell in the range from 500 C to 800 C to produce electrical energy. Additional methods and systems/compositions are also provided.

Adsorption of cellobiohydrolases I onto lignin fractions from dilute acid pretreated Broussonetia papyrifera

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yao, Lan; Yang, Haitao; Yoo, Chang Geun

Broussonetia papyrifera, known as paper mulberry, is a potential feed stock for bioethanol production because of its cellulose-rich composition. Lignin in dilute acid pretreated Broussonetia papyrifera was fractionated to three different fractions, and their physiochemical properties were determined by FT-IR, GPC and NMR analyses. Different structural characteristics were observed from each lignin fraction. Cellobiohydrolases I (CBH) adsorption to each lignin was understood by the lignin properties. The results showed that aliphatic hydroxyl groups in lignin showed positive correlations with the maximum binding ability of CBH onto lignin samples. Also, the contents of phenolic compounds such as p-hydroxyphenyl benzoate (PB), syringylmore » (S) and guaiacyl (G) units in the lignin influenced their CBH binding.« less

Adsorption of cellobiohydrolases I onto lignin fractions from dilute acid pretreated Broussonetia papyrifera

DOE PAGES

Yao, Lan; Yang, Haitao; Yoo, Chang Geun; ...

2017-11-01

Broussonetia papyrifera, known as paper mulberry, is a potential feed stock for bioethanol production because of its cellulose-rich composition. Lignin in dilute acid pretreated Broussonetia papyrifera was fractionated to three different fractions, and their physiochemical properties were determined by FT-IR, GPC and NMR analyses. Different structural characteristics were observed from each lignin fraction. Cellobiohydrolases I (CBH) adsorption to each lignin was understood by the lignin properties. The results showed that aliphatic hydroxyl groups in lignin showed positive correlations with the maximum binding ability of CBH onto lignin samples. Also, the contents of phenolic compounds such as p-hydroxyphenyl benzoate (PB), syringylmore » (S) and guaiacyl (G) units in the lignin influenced their CBH binding.« less

Effect of incorporating finger millet in wheat flour on mixolab behavior, chapatti quality and starch digestibility.

PubMed

Sharma, Bharati; Gujral, Hardeep Singh; Solah, Vicky

2017-09-15

Wheat and finger millet flour (two cultivars) were blended in the ratio (3:1) to form a composite flour and its dough properties were studied on the mixolab. The chapatti making and digestibility behavior of the composite flour was also investigated. The wheat finger millet (WFM) flour blend displayed up to 30.7% higher total phenolic content (TPC), 38.2% higher total flavonoid content (TFC) and 75.4% higher antioxidant activity (AOA) than the wheat flour. Chapattis prepared from the composite blends exhibited lower retrogradation as evident by the mixolab retrogradation index, higher values of soluble starch and soluble amylose in stored chapatti. The slowly digestible starch (SDS) correlated positively (R=0.816, p<0.05) with TPC and water absorption correlated positively (R=0.995, p<0.05) with damage starch content. The chapattis made from the composite flour had higher SDS and resistant starch (RS) values demonstrating potential as a food with functional characteristics. Copyright © 2017 Elsevier Ltd. All rights reserved.

In Vitro Cultivars of Vaccinium corymbosum L. (Ericaceae) are a Source of Antioxidant Phenolics.

PubMed

Contreras, Rodrigo A; Köhler, Hans; Pizarro, Marisol; Zúiga, Gustavo E

2015-04-09

The antioxidant activity and phenolic composition of six in vitro cultured blueberry seedlings were determined. Extracts were prepared in 85% ethanol from 30 days old in vitro cultured plants and used to evaluate the antioxidant capacities that included Ferric reducing antioxidant power (FRAP) and 1,1-diphenyl-2-picrylhydrazin (DPPH•) scavenging ability, total polyphenols (TP) and the partial phenolic composition performed by high performance liquid chromatography with diode array detector (HPLC-DAD), liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS (ESI-QqQ)). All ethanolic extracts from in vitro blueberry cultivars displayed antioxidant activity, with Legacy, Elliott and Bluegold cultivars being the most active. In addition, we observed a positive correlation between phenolic content and antioxidant activity. Our results suggest that the antioxidant activity of the extracts is related to the content of chlorogenic acid myricetin, syringic acid and rutin, and tissue culture of blueberry seedlings is a good tool to obtain antioxidant extracts with reproducible profile of compounds.

Phenolic Components and Antioxidant Activity of Wood Extracts from 10 Main Spanish Olive Cultivars.

PubMed

Salido, Sofía; Pérez-Bonilla, Mercedes; Adams, Robert P; Altarejos, Joaquín

2015-07-29

The chemical composition and radical-scavenging activity of wood samples from 10 main Spanish olive cultivars were studied. The wood samples were collected during the pruning works from trees growing under the same agronomical and environmental conditions. The 10 ethyl acetate extracts were submitted to HPLC-DAD/ESI-MS analysis to determine the phenolic constituents. Seventeen compounds were identified (10 secoiridoids, 3 lignans, 2 phenol alcohols, 1 iridoid, and 1 flavonoid) by comparison with authentic samples. Significant quantitative and qualitative differences were found among olive cultivars. The lignan (+)-1-hydroxypinoresinol 1-O-β-d-glucopyranoside was the major compound in all olive cultivars, except in cultivars 'Farga' and 'Picual'. The multivariate analysis of all data revealed three sets of cultivars with similar compositions. Cultivars 'Gordal sevillana' and 'Picual' had the most distinct chemical profiles. With regard to the radical-scavenging activity, cultivar 'Picual', with oleuropein as the major phenolic, showed the highest activity (91.4 versus 18.6-32.7%).

Thermal behavior of phenol-furfuryl alcohol resin/carbon nanotubes composites

NASA Astrophysics Data System (ADS)

Conejo, L. S.; Costa, M. L.; Oishi, S. S.; Botelho, E. C.

2018-04-01

Phenol-furfuryl alcohol resins (PFA) are excellent candidates to replace existing thermoset matrices used in obtaining insulating systems or carbon materials, both in its pure form and reinforced with nanoscale structures. This work had as main purpose synthesize and investigate thermal characterization of PFA resin and its nanostructured composites with different concentrations of carbon nanotubes (0, 0.1, 0.5 and 1.0 wt%). The DSC analysis was performed to estimate the specific heat (cp) of the cured samples and thermomechanical analysis to find the linear thermal expansion coefficient (α). From these results, the cp values found for the PFA system was similar to that described in the literature for the phenolic resin. The cp increased with the increase in the CNT concentration in the system up to 0.5%. The coefficient of linear thermal expansion obtained by TMA technique for PFA sample was 33.10‑6/°C which was close to the α value of phenolic resin (40 to 80.10‑6/°C).

Identification of phenolic compounds by liquid chromatography-mass spectrometry in seventeen species of wild mushrooms in Central Mexico and determination of their antioxidant activity and bioactive compounds.

PubMed

Yahia, Elhadi M; Gutiérrez-Orozco, Fabiola; Moreno-Pérez, Marco A

2017-07-01

Wild mushrooms are important for the diet of some communities in Mexico. However, limited information exists on their chemical composition, contribution to the diet, and health effects. We characterized seventeen wild mushroom species growing in the state of Queretaro in Central Mexico. Most species analyzed were edible, but also included nonedible, medicinal, poisonous and toxic specimens. Whole mushrooms (caps and stipes) were characterized for water content, color, and total content of phenolic compounds, flavonoids and anthocyanins. In vitro antioxidant capacity was measured by FRAP and DPPH assays. Phenolic compounds were identified and quantified by HPLC-mass spectrometry. All species analyzed were found to possess antioxidant activity in vitro and a wide range of phenolic and organic compounds were identified. Our results add to the limited information available on the composition and potential nutritional and health value of wild mushrooms. Further analyses of their bioactivities are warranted. Copyright © 2017 Elsevier Ltd. All rights reserved.

Multidirectional characterisation of chemical composition and health-promoting potential of Rosa rugosa hips.

PubMed

Olech, Marta; Nowak, Renata; Pecio, Łukasz; Łoś, Renata; Malm, Anna; Rzymowska, Jolanta; Oleszek, Wiesław

2017-03-01

Rugosa rose provides one of the largest hips frequently used in the preparation of pharmaceutical and food products. The aim of work was to conduct multidirectional study of biological activity and chemical composition of Rosa rugosa hips. Antiradical, cytotoxic (against cervical and breast cancer cell lines), antibacterial (against eight bacterial strains) and antifungal potential of the species in question was evaluated. Total contents of phenolics, phenolic acids, flavonoids, tannins, carotenoids and ascorbic acid were determined. LC-ESI-MS/MS analysis was performed in order to investigate closely phenolic acids and flavonoid glycosides. As a result, interesting selective cytotoxic effects on cervical (HeLa) and breast cancer (T47D) cell lines, significant antiradical activity (EC 50 2.45 mg mg -1 DPPH • ) and moderate antimicrobial potential (MIC 0.625-1.25 mg mL -1 ) were observed. Nine phenolic acids and 11 flavonoid glycosides were qualitatively and quantitatively determined, including 7 compounds previously not reported in R. rugosa hips.

In Vitro Cultivars of Vaccinium corymbosum L. (Ericaceae) are a Source of Antioxidant Phenolics

PubMed Central

Contreras, Rodrigo A.; Köhler, Hans; Pizarro, Marisol; Zúñiga, Gustavo E.

2015-01-01

The antioxidant activity and phenolic composition of six in vitro cultured blueberry seedlings were determined. Extracts were prepared in 85% ethanol from 30 days old in vitro cultured plants and used to evaluate the antioxidant capacities that included Ferric reducing antioxidant power (FRAP) and 1,1-diphenyl-2-picrylhydrazin (DPPH•) scavenging ability, total polyphenols (TP) and the partial phenolic composition performed by high performance liquid chromatography with diode array detector (HPLC-DAD), liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS (ESI-QqQ)). All ethanolic extracts from in vitro blueberry cultivars displayed antioxidant activity, with Legacy, Elliott and Bluegold cultivars being the most active. In addition, we observed a positive correlation between phenolic content and antioxidant activity. Our results suggest that the antioxidant activity of the extracts is related to the content of chlorogenic acid myricetin, syringic acid and rutin, and tissue culture of blueberry seedlings is a good tool to obtain antioxidant extracts with reproducible profile of compounds. PMID:26783705

Phenolic composition and antioxidant potential of grain legume seeds: A review.

PubMed

Singh, Balwinder; Singh, Jatinder Pal; Kaur, Amritpal; Singh, Narpinder

2017-11-01

Legumes are a good source of bioactive phenolic compounds which play significant roles in many physiological as well as metabolic processes. Phenolic acids, flavonoids and condensed tannins are the primary phenolic compounds that are present in legume seeds. Majority of the phenolic compounds are present in the legume seed coats. The seed coat of legume seeds primarily contains phenolic acids and flavonoids (mainly catechins and procyanidins). Gallic and protocatechuic acids are common in kidney bean and mung bean. Catechins and procyanidins represent almost 70% of total phenolic compounds in lentils and cranberry beans (seed coat). The antioxidant activity of phenolic compounds is in direct relation with their chemical structures such as number as well as position of the hydroxyl groups. Processing mostly leads to the reduction of phenolic compounds in legumes owing to chemical rearrangements. Phenolic content also decreases due to leaching of water-soluble phenolic compounds into the cooking water. The health benefits of phenolic compounds include acting as anticarcinogenic, anti-thrombotic, anti-ulcer, anti-artherogenic, anti-allergenic, anti-inflammatory, antioxidant, immunemodulating, anti-microbial, cardioprotective and analgesic agents. This review provides comprehensive information of phenolic compounds identified in grain legume seeds along with discussing their antioxidant and health promoting activities. Copyright © 2017 Elsevier Ltd. All rights reserved.

Mineral and Phytochemical Profiles and Antioxidant Activity of Herbal Material from Two Temperate Astragalus Species

PubMed Central

Dagilytė, Audronė; Lemežienė, Nijolė

2018-01-01

Only a few species of the large Astragalus genus, widely used for medicinal purposes, have been thoroughly studied for phytochemical composition. The aim of our research was to investigate the rarely studied species A. glycyphyllos L. and A. cicer L. for the distribution of mineral elements and phytochemicals in whole plants at two growth stages and in morphological fractions. We also investigated the capacity of the plant extracts to scavenge 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals and to chelate ferrous ions. Chemical composition and antioxidant properties depended on species, maturity, and plant part. Herbal material of A. glycyphyllos was richer in Fe, total phenolics, and flavonoids, whereas extracts of A. cicer showed a higher antioxidant activity. Young plants had more isoflavones, showed greater quenching of DPPH radicals, and exhibited better mineral profiles than flowering plants. Among plant parts, leaves were the most valuable plant material according to most characteristics investigated. Isoflavone concentration in flowers was lower than in leaves and stems. None of the Astragalus samples contained detectable amounts of the alkaloid swainsonine. The study demonstrates the potential of plant material from two Astragalus species as a valuable source of iron, phenolic substances including isoflavones, free-radical scavengers, and Fe2+ chelators for pharmaceutical use. PMID:29581980

Phytochemical analysis and antioxidant capacity of BM-21, a bioactive extract rich in polyphenolic metabolites from the sea Grass Thalassia testudinum.

PubMed

Regalado, Erik L; Menendez, Roberto; Valdés, Olga; Morales, Ruth A; Laguna, Abilio; Thomas, Olivier P; Hernandez, Yasnay; Nogueiras, Clara; Kijjoa, Anake

2012-01-01

The aqueous ethanol extract of Thalassia testudinum leaves (BM-21) is now being developed in Cuba as an herbal medicine due to its promising pharmacological properties. Although some interesting biological activities of BM-21 have already been reported, its chemical composition remains mostly unknown. Thus, we now describe the qualitative and quantitative analyzes of BM-21 using standard phytochemical screening techniques, including colorimetric quantification, TLC and HPLC analyses. Phytochemical investigation of BM-21 resulted in the isolation and identification of a new phenolic sulfate ester (1), along with ten previously described phenolic derivatives (2-11), seven of which have never been previously reported from the genus Thalassia. The structures of these compounds were established by analysis of their spectroscopic (1D and 2D NMR) and spectrometric (HRMS) data, as well as by comparison of these with those reported in the literature. Furthermore, BM-21 was found to exhibit strong antioxidant activity in four different free radical scavenging assays (HO*, RO2*, O2-* and DPPH*). Consequently, this is the first study which highlights the phytochemical composition of BM-21 and demonstrates that this product is a rich source of natural antioxidants with potential applications in pharmaceutical, cosmetic and food industries.

Poly(3-hydroxybutyrate)-ethyl cellulose based bio-composites with novel characteristics for infection free wound healing application.

PubMed

Iqbal, Hafiz M N; Kyazze, Godfrey; Locke, Ian Charles; Tron, Thierry; Keshavarz, Tajalli

2015-11-01

A series of bio-composites including poly3-hydroxybutyrate [P(3HB)] grafted ethyl cellulose (EC) stated as P(3HB)-EC were successfully synthesised. Furthermore, natural phenols e.g., p-4-hydroxybenzoic acid (HBA) and ferulic acid (FA) were grafted onto the newly developed P(3HB)-EC-based bio-composites under laccase-assisted environment without the use of additional initiators or crosslinking agents. The phenol grafted bio-composites were critically evaluated for their antibacterial and biocompatibility features as well as their degradability in soil. In particular, the results of the antibacterial evaluation for the newly developed bio-composites indicated that 20HBA-g-P(3HB)-EC and 15FA-g-P(3HB)-EC bio-composites exerted strong bactericidal and bacteriostatic activity against Gram(-)E. coli NTCT 10418 as compared to the Gram(+)B. subtilis NCTC 3610. This study shows further that at various phenolic concentrations the newly synthesised bio-composites remained cytocompatible with human keratinocyte-like HaCaT skin cells, as 100% cell viability was recorded, in vitro. As for the degradation, an increase in the degradation rate was recorded during the soil burial analyses over a period of 42 days. These findings suggest that the reported bio-composites have great potential for use in wound healing; covering the affected skin area which may favour tissue repair over shorter periods. Copyright © 2015 Elsevier B.V. All rights reserved.

Oil composition and characterisation of phenolic compounds of Opuntia ficus-indica seeds.

PubMed

Chougui, Nadia; Tamendjari, Abderezak; Hamidj, Wahiba; Hallal, Salima; Barras, Alexandre; Richard, Tristan; Larbat, Romain

2013-08-15

The seed composition of four varieties of Opuntia ficus-indica growing in Algeria was investigated. Seeds ground into a fine powder were first, subjected to oil extraction and fatty acids analysis. The phenolic compounds were then extracted from the defatted powder of seeds in order to be quantified and characterised by liquid chromatography coupled to mass spectrometry (LC-MS(n)) and to nuclear magnetic resonance (LC-NMR) approaches. In addition, an evaluation of the antioxidant activity of the phenolic extracts was investigated. Gas chromatography analysis of the seed oil showed high percentages of linoleic acid in the four varieties ranging from 58% to 63%. The phenolic profile of the Opuntia ficus-indica seeds displayed a high complexity, with more than 20 compounds detected at 330 nm after the LC separation. Among them, three isomers of feruloyl-sucrose were firmly identified and another was strongly supposed to be a sinapoyl-diglycoside. High correlations were found between phenolic content in the defatted seed extracts and their antioxidant activity. The data indicate that the defatted cactus seed wastes still contain various components that constitute a source for natural foods. Copyright © 2013 Elsevier Ltd. All rights reserved.

Phenolic composition and radical scavenging activity of sweetpotato-derived shochu distillery by-products treated with koji.

PubMed

Yoshimoto, Makoto; Kurata-Azuma, Rie; Fujii, Makoto; Hou, De-Xing; Ikeda, Kohji; Yoshidome, Tomohisa; Osako, Miho

2004-12-01

Phenolic composition and radical scavenging activity in the shochu distillery by-products of sweetpotato (Ipomoea batatas L.) treated with koji (Aspergillus awamori mut.) and cellulase (Cellulosin T2) were investigated to develop new uses. Koji and Cellulosin T2 treatment of shochu distillery by-products from sweetpotatoes, rice, and barley increased phenolic content. Caffeic acid was identified as a dominant phenolic component in the shochu distillery by-products of the sweetpotato. Adding koji and/or Cellulosin T2 to the shochu distillery by-product indicated that koji was involved in caffeic acid production. Caffeic acid was not detected in raw or steamed roots of "Koganesengan", the material of sweetpotato for shochu production, suggesting that it is produced during shochu fermentation. The phenolic content and radical scavenging activity the shochu distillery by-product treated with koji and Cellulosin T2 were superior to those of commercial vinegar. These results suggest that koji treatment of sweetpotato-derived shochu distillery by-products has potential for food materials with physiological functions. Further koji treatment of sweetpotato shochu-distillery by-products may be applicable to mass production of caffeic acid.

Phenolic profile and effect of growing area on Pistacia lentiscus seed oil.

PubMed

Mezni, Faten; Slama, Awatef; Ksouri, Riadh; Hamdaoui, Ghaith; Khouja, Mohamed Larbi; Khaldi, Abdelhamid

2018-08-15

In this investigation, we aimed to study, for the first time, the phenolic composition of Pistacia lentiscus seed oils from different growing areas. Extraction of the phenolic fraction from oils was done by methanol/water. Phenolic profiles were determined using chromatographic analysis by High Performance Liquid Chromatography (HPLC-DAD/MSD) and its quantification was done using an internal standard which is unidentified in the studied oil (syringic acid). Forty phenolic compounds were quantified and only eighteen of them were identified. The eight studied oils showed different phenolic profiles. The total phenols amount varied from 538.03 mg/kg oil in Jbel Masour oils to 4260.57 mg/kg oil in oils from Kef Erraai. The highest amount of secoiridoids was reached by Bouchoucha oil containing 366.71 mg/kg oil of Oleuropein aglycon. Oils from Kef Erraai locality contained the highest concentrations in flavonols (377.44 mg/kg oil) and in phenolic acids (2762.67 mg/kg oil). Copyright © 2018 Elsevier Ltd. All rights reserved.

Effects of fungal degradation on the CuO oxidation products of lignin: A controlled laboratory study

NASA Astrophysics Data System (ADS)

Hedges, John I.; Blanchette, Robert A.; Weliky, Karen; Devol, Allan H.

1988-11-01

Duplicate samples of birch wood were degraded for 0, 4, 8 and 12 weeks by the white-rot fungus, Phlebia tremellosus, and for 12 weeks by 6 other white-rot and brown-rot fungi. P. tremellosus caused progressive weight losses and increased the H/C and O/C of the remnant wood by preferentially degrading the lignin component of the middle lamellae. This fungus increased the absolute (weight loss-corrected) yield of the vanillic acid CuO reaction product above its initial level and exponentially decreased the absolute yields of all other lignin-derived phenols. Total yields of syringyl phenols were decreased 1.5 times as fast as total vanillyl phenol yields. Within both phenol families, aldehyde precursors were degraded faster than precursors of the corresponding ketones, which were obtained in constant proportion to the total phenol yield. Although two other white-rot fungi caused similar lignin compositional trends, a fourth white-rot species, Coriolus versicolor, simultaneously eroded all cell wall components and did not concentrate polysaccharides in the remnant wood. Wood degraded by the three brown-rot fungi exhibited porous cell walls with greatly reduced integrity. The brown-rot fungi also preferentially attacked syringyl structural units, but degraded all phenol precursors at a much slower rate than the white-rotters and did not produce excess vanillic acid. Degradation by P. tremellosus linearly increased the vanillic acid/vanillin ratio, (Ad/Al)v, of the remnant birch wood throughout the 12 week degradation study and exponentially decreased the absolute yields of total vanillyl phenols, total syringyl phenols and the syringyl/vanillyl phenol ratio, S/V. At the highest (Ad/Al)v of 0.50 (12 week samples), total yields of syringyl and vanillyl phenols were decreased by 65% and 80%, respectively, with a resulting reduction of 40% in the original S/V. Many of the diagenetically related compositional trends that have been previously reported for lignins in natural environments can be explained by white-rot fungal degradation.

Characterization of polyphenols and antioxidant potential of white grape pomace byproducts (Vitis vinifera L.).

PubMed

González-Centeno, María Reyes; Jourdes, Michael; Femenia, Antoni; Simal, Susana; Rosselló, Carmen; Teissedre, Pierre-Louis

2013-11-27

A detailed assessment of the total phenolic and total tannin contents, the monomeric and oligomeric flavan-3-ol composition, the proanthocyanidin profile, and the antioxidant potential of the grape pomace byproducts (considered as a whole, both skins and seeds), derived from four white grape varieties (Vitis vinifera L.), was performed. Significant differences (p < 0.05) of the total phenolic content, total tannin content, and antioxidant capacity of grape pomace byproducts were observed among the different grape varieties studied. For the first time in the literature, the particular flavan-3-ol composition of the four grape varieties investigated was described for the whole fraction of their grape pomace byproducts. The phenolic composition and antioxidant capacity of grape pomaces were compared to those of their corresponding stems. The global characterization of these white grape varieties provided a basis for an integrated exploitation of both winemaking byproducts as potential, inexpensive, and easily available sources of bioactive compounds for the pharmaceutical, cosmetic, and food industries.

Wine Chemical Composition and Radical Scavenging Activity of Some Cabernet Franc Clones.

PubMed

Popovic-Djordjevic, Jelena; Pejin, Boris; Dramicanin, Aleksandra; Jovic, Sonja; Vujovic, Dragan; Zunic, Dragoljub; Ristic, Renata

2017-01-01

Three clones of Cabernet Franc (Nos. 02, 010 and 012) were selected in the last phase of clonal selection in Serbia. Wines made from each clone were assessed for quality parameters and taste during five consecutive vintages (2008-2012) and compared to the standard. The wine quality was determined based on the following parameters: alcohol, total extract, anthocyanins, tannins, pH, titratable acidity, volatile acidity, aldehydes, esters and reducing sugars, relative density, ash, colour, tonality, and tasting score. In the last year of the study, grapes and wines of Cabernet Franc clones and a standard were subjected to a chemical analysis of their phenolic composition, resveratrol and radical scavenging activity. In the last year of the study, grapes and wines of Cabernet Franc clones and a standard were subjected to a chemical analysis of their phenolic composition, resveratrol and radical scavenging activity. Chemical analyses of grapes and wines along with sensory and radical scavenging activity evaluations were done according to the standard procedures. The wines of the clone No. 010 showed some superior properties compared to the other two clones and the standard; in five-year period the average concentration of anthocyanins (179±3.8 mg/L) and polyphenolics (1.85±0.02 g/L) was significantly higher than in wines of clones and the standard, (168-173 mg/L and 1.63-1.74 g/L for anthocyanins and phenolics, respectively). Furthermore, the same clone had a higher alcohol content (13.97±0.03%) in each year of the study, which indicated that it ripened faster than other clones (13.06-13.08 %) and compared to the standard (13.04±0.07%). This finding suggested that the clone No. 010 could possibly have a significant economic impact and further increase popularity of Cabernet Franc in a cooler climate viticultural region. It was also found to have the highest contents of aldehydes (488±1.54 mg/L) and esters (322±0.71 mg/L) compared to aldehydes (452-467 mg/L) and esters (290-310 mg/L) measured in other wines. Finally, the highest amount of phenolic compounds (1220±40 mg/kg) and resveratrol (70±3.3 mg/kg) were found in the grapes of the clone No. 010. The present study revealed a strong correlation of total phenolic contents and anthocyanins with radical scavenging activities (0.936 and 0.929, P<0.001, respectively) indicating that this activity of wines was derived mainly from their phenolic compounds. The wine of the clone No. 010 contained the highest concentration of aldehydes, esters, anthocyanins, polyphenolics and resveratrol and consequently achieved the best tasting score. This clone may offer a new Cabernet Franc wine with geographical indication. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Proceedings of the 7th Semiannual Meeting of the Nozzle Initiative Industry Advisory Committee on Standardization of Carbon-Phenolic Test Methods and Specifications

NASA Technical Reports Server (NTRS)

Hall, William B. (Compiler); Pinoli, Pat C. (Compiler); Upton, Cindy G. (Compiler)

1991-01-01

The application of carbon fibers and fabrics (CF) for producing rocket nozzles is discussed. These materials which are essential for fabricating the carbon composites used in aerospace systems gasify when exposed to high temperatures and the mechanical properties of the composites degrade. The oxidation kinetics under isothermal (IC) and non-isothermal (NIC) conditions are examined and a comparison is made between the characteristics of IC and NIC oxidation. Several CF, chars, and carbon blacks were examined, including a microporous char, a graphitized rayon fabric, and several carbonized rayon fabrics. A summary is given of the advantages and drawbacks of isothermal and non-isothermal oxidation of carbons. The proceedings are assembled in the form of a roundtable discussion.

Total phenolic contents and free-radical scavenging activities of grape (Vitis vinifera L.) and grape products.

PubMed

Keser, Serhat; Celik, Sait; Turkoglu, Semra

2013-03-01

Grape is one of the world's largest fruit crops, with an approximate annual production of 58 million metric tons, and it is well known that the grape skins, seeds and stems, waste products generated during wine and grape juice processing, are rich sources of polyphenols. It contains flavonoids, phenolic acids and stilbenes. In this study, we tried to determine antioxidant properties and phenolic contents of grape and grape products (fresh fruit, seed, dried fruit, molasses, pestil, vinegar) of ethanol and water extracts. Antioxidant properties of extracts were investigated by DPPH(√), ABTS(√+), superoxide, H(2)O(2) scavenging, reducing power, metal chelating activity and determination of total phenolic contents. The seed extracts revealed highest ABTS(√+), DPPH(√), H(2)O(2) scavenging and reducing power activities. Furthermore, these extracts showed higher total phenolic contents than other grape product extracts.

Properties of Bread Dough with Added Fiber Polysaccharides and Phenolic Antioxidants: A Review

PubMed Central

Sivam, Anusooya S; Sun-Waterhouse, Dongxiao; Quek, SiewYoung; Perera, Conrad O

2010-01-01

During breadmaking, different ingredients are used to ensure the development of a continuous protein network that is essential for bread quality. Interests in incorporating bioactive ingredients such as dietary fiber (DF) and phenolic antioxidants into popular foods such as bread have grown rapidly, due to the increased consumer health awareness. The added bioactive ingredients may or may not promote the protein cross-links. Appropriate cross-links among wheat proteins, fiber polysaccharides, and phenolic antioxidants could be the most critical factor for bread dough enhanced with DF and phenolic antioxidants. Such cross-links may influence the structure and properties of a bread system during baking. This article presents a brief overview of our current knowledge of the fate of the key components (wheat proteins, fibers, and phenolic antioxidants) and how they might interact during bread dough development and baking. PMID:21535512

Antioxidant, Antimicrobial Effects and Phenolic Profile of Lycium barbarum L. Flowers.

PubMed

Mocan, Andrei; Vlase, Laurian; Vodnar, Dan Cristian; Gheldiu, Ana-Maria; Oprean, Radu; Crișan, Gianina

2015-08-17

L. barbarum L. is a widely-accepted nutraceutical presenting highly advantageous nutritive and antioxidant properties. Its flowers have been previously described as a source of diosgenin, β-sitosterol and lanosterol that can be further pharmaceutically developed, but no other data regarding their composition is available. The purpose of this work was to investigate the chemical constituents, antioxidant and antimicrobial activities of L. barbarum flowers, as an alternative resource of naturally-occurring antioxidant compounds. The free radical scavenging activity of the ethanolic extract was tested by TEAC, two enzymatic assays with more physiological relevance and EPR spectroscopy. The presence of several phenolic compounds, such as chlorogenic, p-coumaric and ferulic acids, but also isoquercitrin, rutin and quercitrin, was assessed by an HPLC/MS method. The antioxidant assays revealed that the extract exhibited a moderate antioxidant potential. The antimicrobial activity was mild against Gram-positive bacteria and lacking against Escherichia coli. These findings complete the scarce existing data and offer new perspectives for further pharmaceutical valorization of L. barbarum flowers.

Flight and ground tests of a very low density elastomeric ablative material

NASA Technical Reports Server (NTRS)

Olsen, G. C.; Chapman, A. J., III

1972-01-01

A very low density ablative material, a silicone-phenolic composite, was flight tested on a recoverable spacecraft launched by a Pacemaker vehicle system; and, in addition, it was tested in an arc heated wind tunnel at three conditions which encompassed most of the reentry heating conditions of the flight tests. The material was composed, by weight, of 71 percent phenolic spheres, 22.8 percent silicone resin, 2.2 percent catalyst, and 4 percent silica fibers. The tests were conducted to evaluate the ablator performance in both arc tunnel and flight tests and to determine the predictability of the albator performance by using computed results from an existing one-dimensional numerical analysis. The flight tested ablator experienced only moderate surface recession and retained a smooth surface except for isolated areas where the char was completely removed, probably following reentry and prior to or during recovery. Analytical results show good agreement between arc tunnel and flight test results. The thermophysical properties used in the analysis are tabulated.

Effect of steam explosion-assisted extraction on phenolic acid profiles and antioxidant properties of wheat bran.

PubMed

Liu, Liya; Zhao, Mengli; Liu, Xingxun; Zhong, Kui; Tong, Litao; Zhou, Xianrong; Zhou, Sumei

2016-08-01

The majority of phenolic acids in wheat bran are bound to the cell walls. Hence, a high proportion of phenolic acids cannot be extracted with conventional extraction methods. This study aimed to investigate the efficiency of steam explosion pre-treatment in increasing the extractability of phenolic compounds from wheat bran. Bound phenolic acids (BPA) can be released by steam explosion-assisted extraction. Within the experimental range, soluble free phenolic acids (FPA) and soluble conjugated phenolic acids (CPA) increased gradually with residence time and temperature. After steam explosion at 215 °C for 120 s, the total FPA and CPA reached 6671.8 and 2578.6 µg GAE g(-1) bran, respectively, which was about 39-fold and seven-fold higher than that of the untreated sample. Ferulic acid, the major individual phenolic acids in bran, increased from 55.7 to 586.3 µg g(-1) for FPA, and from 44.9 to 1108.4 µg g(-1) for CPA. The antioxidant properties of FPA and CPA extracts were significantly improved after treated. Correlation analysis indicated that the antioxidant capacity was in close relationship with phenolic content in FPA and CPA. Steam explosion pre-treatment could be effectively used to release of BPA and enhance the antioxidant capacity of wheat bran. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Determination of free, esterified, glycosylated and insoluble-bound phenolics composition in the edible part of araticum fruit (Annona crassiflora Mart.) and its by-products by HPLC-ESI-MS/MS.

PubMed

Arruda, Henrique Silvano; Pereira, Gustavo Araujo; de Morais, Damila Rodrigues; Eberlin, Marcos Nogueira; Pastore, Glaucia Maria

2018-04-15

Phenolics present in the free, esterified, glycosylated and insoluble-bound forms of araticum pulp, peel and seed were for the first time characterized and quantified using HPLC-ESI-MS/MS. Levels of total phenolics, flavonoids, condensed tannins and antioxidant activities from araticum fruit followed the order peel > pulp > seed. Overall, insoluble-bound and esterified phenolics were the dominant forms of phenolics from araticum fruit parts and the highest contributors to their antioxidant activities. Extracts were found to contain contrasting levels of phenolics that were specific to each fruit part. From 10 phenolics quantified in araticum fruit, catechin and epicatechin were the major ones from pulp and peel, whereas seed displayed caffeic acid, catechin and epicatechin as its main phenolics. Araticum fruit was found to provide a good source of phenolics, and the full exploitation of this fruit may find applications in the food, cosmetic and pharmaceutical industries. Copyright © 2017 Elsevier Ltd. All rights reserved.

In-Depth Two-Year Study of Phenolic Profile Variability among Olive Oils from Autochthonous and Mediterranean Varieties in Morocco, as Revealed by a LC-MS Chemometric Profiling Approach.

PubMed

Bajoub, Aadil; Medina-Rodríguez, Santiago; Olmo-García, Lucía; Ajal, El Amine; Monasterio, Romina P; Hanine, Hafida; Fernández-Gutiérrez, Alberto; Carrasco-Pancorbo, Alegría

2016-12-28

Olive oil phenolic fraction considerably contributes to the sensory quality and nutritional value of this foodstuff. Herein, the phenolic fraction of 203 olive oil samples extracted from fruits of four autochthonous Moroccan cultivars ("Picholine Marocaine", "Dahbia", "Haouzia" and "Menara"), and nine Mediterranean varieties recently introduced in Morocco ("Arbequina", "Arbosana", "Cornicabra", "Frantoio", "Hojiblanca", "Koroneiki", "Manzanilla", "Picholine de Languedoc" and "Picual"), were explored over two consecutive crop seasons (2012/2013 and 2013/2014) by using liquid chromatography-mass spectrometry. A total of 32 phenolic compounds (and quinic acid), belonging to five chemical classes (secoiridoids, simple phenols, flavonoids, lignans and phenolic acids) were identified and quantified. Phenolic profiling revealed that the determined phenolic compounds showed variety-dependent levels, being, at the same time, significantly affected by the crop season. Moreover, based on the obtained phenolic composition and chemometric linear discriminant analysis, statistical models were obtained allowing a very satisfactory classification and prediction of the varietal origin of the studied oils.

The impact of drying techniques on phenolic compound, total phenolic content and antioxidant capacity of oat flour tarhana.

PubMed

Değirmencioğlu, Nurcan; Gürbüz, Ozan; Herken, Emine Nur; Yıldız, Aysun Yurdunuseven

2016-03-01

In this study, the changes in phenolic composition, total phenolic content, and antioxidant capacity of tarhanas supplemented with oat flour (OF) at the levels of 20-100% (w/w) after three drying treatments (sun-, oven-, and microwave drying) were investigated. A total of seventeen phenolic standards have been screened in tarhanas, and the most abundant flavonol and phenolic acid compounds were kaempferol (23.62mg/g) and 3-hydroxy-4-metoxy cinnamic acid (9.60mg/g). The total phenolic content amount gradually increased with the addition of OF to tarhana, but decidedly higher total phenolic content was found in samples oven dried at 55°C as compared with other methods. The microwave- and oven dried tarhana samples showed higher TEACDPPH and TEACABTS values than those dried with the other methods, respectively, in higher OF amounts. Consequently, oven- and microwave-drying can be recommended to retain the highest for phenolic compounds as well as maximal antioxidant capacity in OF supplemented tarhana samples. Copyright © 2015 Elsevier Ltd. All rights reserved.

Identification of Phenolic Acids and Flavonoids in Monofloral Honey from Bangladesh by High Performance Liquid Chromatography: Determination of Antioxidant Capacity

PubMed Central

Moniruzzaman, Mohammed; Yung An, Chua; Rao, Pasupuleti Visweswara; Hawlader, Mohammad Nurul Islam; Azlan, Siti Amirah Binti Mohd; Sulaiman, Siti Amrah; Gan, Siew Hua

2014-01-01

The aim of the present study was to characterize the phenolic acids, flavonoids, and antioxidant properties of monofloral honey collected from five different districts in Bangladesh. A new high performance liquid chromatography (HPLC) equipped with a UV detector method was developed for the identification of the phenolic acids and flavonoids. A total of five different phenolic acids were identified, with the most abundant being caffeic acid, benzoic acid, gallic acid, followed by chlorogenic acid and trans-cinnamic acid. The flavonoids, kaempferol, and catechin were most abundant, followed by myricetin and naringenin. The mean moisture content, total sugar content, and color characteristics of the honey samples were 18.36 ± 0.95%, 67.40 ± 5.63 g/100 g, and 129.27 ± 34.66 mm Pfund, respectively. The mean total phenolic acids, total flavonoid content, and proline content were 199.20 ± 135.23, 46.73 ± 34.16, and 556.40 ± 376.86 mg/kg, respectively, while the mean FRAP values and DPPH radical scavenging activity were 327.30 ± 231.87 μM Fe (II)/100 g and 36.95 ± 20.53%, respectively. Among the different types of honey, kalijira exhibited the highest phenolics and antioxidant properties. Overall, our study confirms that all the investigated honey samples are good sources of phenolic acids and flavonoids with good antioxidant properties. PMID:25045696

Anti-oxidant studies and anti-microbial effect of Origanum vulgare Linn in combination with standard antibiotics

PubMed Central

Bharti, Veni; Vasudeva, Neeru; Kumar, Suresh

2014-01-01

Background: Origanum is one of the over 200 genera in the Lamiaceae (mint family), and this genus includes culinary, fragrant, and medicinal properties. The plant is reported to contain anti-microbial properties, but it lacks combination studies with that of synthetic antibiotics. Aim: To investigate the anti-oxidant and anti-microbial interaction studies of Origanum vulgare with standard drugs against Bacillus species of bacteria and Aspergillus niger. Materials and Methods: The anti-oxidant properties of phenolic, non-phenolic fractions of chloroform extract and volatile oil were evaluated by free radical-scavenging, hydrogen peroxide radical-scavenging assay, reducing power, and metal chelating assays. Results: The minimum inhibitory concentration and fractional inhibitory concentration index were determined which demonstrates the behavior of volatile oil, phenolic, and non-phenolic fractions of volatile oil with that of ciprofloxacin and fluconazole. The IC50 value for volatile oil was found to be 15, 30, and 30 μg/ml and that of phenolic fraction was 60, 120, and 120 μg/ml for free radical-scavenging, hydrogen peroxide-scavenging, and metal chelating assays respectively. Non-phenolic fraction was found to act antagonistically along with ciprofloxacin against B. cereus and B. subtilis, while the phenolic fraction exhibited indifferent activity along with ciprofloxacin against both the bacterial strains. Conclusion: This combination of drug therapy will not only prove effective in antibiotic resistance, but these natural constituents will also help in preventing body from harmful radicals which lead to fatal diseases. PMID:25364204

Polyphenolic composition and antioxidant capacity of legume based swards are affected by light intensity in a Mediterranean agroforestry system.

PubMed

Re, Giovanni Antonio; Piluzza, Giovanna; Sanna, Federico; Molinu, Maria Giovanna; Sulas, Leonardo

2018-06-01

In Mediterranean grazed woodlands, microclimate changes induced by trees influence the growth and development of the understory, but very little is known about its polyphenolic composition in relation to light intensity. We investigated the bioactive compounds and antioxidant capacity of different legume-based swards and variations due to full sunlight and partial shade. The research was carried out in a cork oak agrosilvopastoral system in Sardinia. The highest values of DPPH reached 7 mmol TEAC 100 g -1 DW, total phenolics 67.1 g GAE kg -1 DW and total flavonoids 7.5 g CE kg -1 DW. Compared to full sunlight, partial shade reduced DPPH values by 29 and 42%, and the total phenolic content by 23 and 53% in 100% legume mixture and semi natural pasture. Twelve phenolic compounds were detected: chlorogenic acid in 80% legume mixture (partial shade) and verbascoside in pure sward of bladder clover (full sunlight) were the most abundant. Light intensity significantly affected antioxidant capacity, composition and levels of phenolic compounds. Our results provide new insights into the effects of light intensity on plant secondary metabolites from legume based swards, underlining the important functions provided by agroforestry systems. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Effects of Moisture and Other Contaminants in Friction Composites

DTIC Science & Technology

1993-01-30

NC 126, (Cardolite Corporation, Newark, NJ), a cashew nut shell liquid modified phenolic resin. NC126 is different from a straight phenolic resin in...that there is an alkyl chain substituent in the meta position of the phenol. The resin is derived from cashew nut shell liquid and is a solid...crosslinked cashew resin and is often referred to as cashew particles. The friction materials were processed by compression molding at 160 °C and 1000 psi

Antioxidant and antimicrobial properties of Teucrium arduini L. (Lamiaceae) flower and leaf infusions (Teucrium arduini L. antioxidant capacity).

PubMed

Samec, D; Gruz, J; Strnad, M; Kremer, D; Kosalec, I; Grubesić, R Jurisić; Karlović, K; Lucic, A; Piljac-Zegarac, J

2010-01-01

Antioxidant and antimicrobial activities, as well as total phenol (TP, Folin-Ciocalteu method) and phenolic acid (UPLC-MS/MS) contents of leaf and flower infusions of Teucrium arduini L. from six different mountainous localities in Croatia (Ucka, Vosac, Sveti Jure, Snjeznica, Vaganac, Susanj) were analysed in this study. Antioxidant capacity was evaluated using the ferric reducing/antioxidant power (FRAP) assay, as well as 2,2-diphenyl-1-picrylhydrazyl (DPPH), and 2,2'-azinobis (3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical scavenging assays. The antioxidant potency composite index (ACI), giving equal weight to all three methods used to quantify antioxidant capacity, was the highest for the sample from Vosac (96.7) among flower infusions, while maximum ACI (100) was determined for the infusion from Ucka among leaf infusions. Strong positive correlation was found between the total phenols and ACI for leaf (r=0.953) and flower (r=0.977) infusions. Our results point to significantly (p<0.05) different TP content between leaf and flower infusions, as well as across localities. Leaf infusions of T. arduini from Susanj exhibited marked antibacterial activity against Staphylococcus aureus, while none of the tested infusions exhibited antimicrobial activity against gram-negative bacterial species, or the tested fungal species. Copyright 2009 Elsevier Ltd. All rights reserved.

Optimisation of phenolic extraction from Averrhoa carambola pomace by response surface methodology and its microencapsulation by spray and freeze drying.

PubMed

Saikia, Sangeeta; Mahnot, Nikhil Kumar; Mahanta, Charu Lata

2015-03-15

Optimised of the extraction of polyphenol from star fruit (Averrhoa carambola) pomace using response surface methodology was carried out. Two variables viz. temperature (°C) and ethanol concentration (%) with 5 levels (-1.414, -1, 0, +1 and +1.414) were used to design the optimisation model using central composite rotatable design where, -1.414 and +1.414 refer to axial values, -1 and +1 mean factorial points and 0 refers to centre point of the design. The two variables, temperature of 40°C and ethanol concentration of 65% were the optimised conditions for the response variables of total phenolic content, ferric reducing antioxidant capacity and 2,2-diphenyl-1-picrylhydrazyl scavenging activity. The reverse phase-high pressure liquid chromatography chromatogram of the polyphenol extract showed eight phenolic acids and ascorbic acid. The extract was then encapsulated with maltodextrin (⩽ DE 20) by spray and freeze drying methods at three different concentrations. Highest encapsulating efficiency was obtained in freeze dried encapsulates (78-97%). The obtained optimised model could be used for polyphenol extraction from star fruit pomace and microencapsulates can be incorporated in different food systems to enhance their antioxidant property. Copyright © 2014 Elsevier Ltd. All rights reserved.

Influences of harvest date and location on the levels of ß-carotene, ascorbic acid, total phenols, in vitro antioxidant capacity, and phenolic profiles of five commercial varieties of mango (Mangifera indica L.)

USDA-ARS?s Scientific Manuscript database

Mango (Mangifera indica L.) is a tropical fruit crop grown worldwide with widely attributed nutritional and health-promoting properties. Extensive studies have been made of the high concentrations of phenolic antioxidants in the peel, seeds, and leaves of mango, yet less is known about the phenolic ...

Effects of organic and conventional cultivation methods on composition of eggplant fruits.

PubMed

Raigón, María D; Rodríguez-Burruezo, Adrián; Prohens, Jaime

2010-06-09

Organic food is associated by the general public with improved nutritional properties, and this has led to increasing demand for organic vegetables. The effects of organic and conventional cultivation methods on dry matter, protein, minerals, and total phenolic content has been studied for two successive years in two landraces and one commercial hybrid of eggplant. In the first year, organically produced eggplants had higher mean contents (expressed on a fresh weight basis) of K (196 vs 171 mg 100 g(-1)), Ca (11.1 vs 8.7 mg 100 g(-1)), Mg (6.0 vs 4.6 mg 100 g(-1)), and total phenolics (49.8 vs 38.2 mg 100 g(-1)) than conventionally grown eggplants. In the second year, in which matched plots having a history of organic management were cultivated following organic or conventional fertilization practices, organically produced eggplants still had higher contents of K (272 vs 249 mg 100 g(-1)) and Mg (8.8 vs 7.6), as well as of Cu (0.079 vs 0.065 mg 100 g(-1)), than conventionally fertilized eggplants. Conventionally cultivated eggplants had a higher polyphenol oxidase activity than organically cultivated ones (3.19 vs 2.17 enzyme activity units), although no differences in browning were observed. Important differences in mineral concentrations between years were detected, which resulted in many correlations among mineral contents being significant. The first component of the principal component analysis separates the eggplants according to year, whereas the second component separates them according to the cultivation method (organic or conventional). Overall, the results show that organic management and fertilization have a positive effect on the accumulation of certain beneficial minerals and phenolic compounds in eggplant and that organically and conventionally produced eggplants might be distinguished according to their composition profiles.

Soil Types Effect on Grape and Wine Composition in Helan Mountain Area of Ningxia

PubMed Central

Wang, Rui; Sun, Quan; Chang, Qingrui

2015-01-01

Different soil types can significantly affect the composition of wine grapes and the final wine product. In this study, the effects of soil types on the composition of Cabernet Sauvignon grapes and wine produced in the Helan Mountains were evaluated. Three different representative soil types—aeolian, sierozem and irrigation silting soil were studied. The compositions of grapes and wines were measured, and in addition, the weights of 100-berry samples were determined. The grapes that grown on the aeolian and sierozem soils matured sooner than those grown on the irrigation silting soil. The highest sugar content, total soluble solids content, sugar to acid ratio and anthocyanin content were found in the grapes that grown on the aeolian soil. The wine produced from this soil had improved chroma and tone and higher-quality phenols. The grapes grown on the sierozem soil had the highest total phenol and tannin contents, which affected the wine composition. The grapes grown on the irrigation silting soil had higher acidities, but the remaining indices were lower. In addition, the grapes grown on the aeolian soil resulted in wines with better chroma and aroma. The sierozem soil was beneficial for the formation of wine tannins and phenols and significantly affected the wine composition. The quality of the grapes from the irrigation silting soil was relatively low, resulting in lower-quality wine. PMID:25706126

Soil types effect on grape and wine composition in Helan Mountain area of Ningxia.

PubMed

Wang, Rui; Sun, Quan; Chang, Qingrui

2015-01-01

Different soil types can significantly affect the composition of wine grapes and the final wine product. In this study, the effects of soil types on the composition of Cabernet Sauvignon grapes and wine produced in the Helan Mountains were evaluated. Three different representative soil types--aeolian, sierozem and irrigation silting soil were studied. The compositions of grapes and wines were measured, and in addition, the weights of 100-berry samples were determined. The grapes that grown on the aeolian and sierozem soils matured sooner than those grown on the irrigation silting soil. The highest sugar content, total soluble solids content, sugar to acid ratio and anthocyanin content were found in the grapes that grown on the aeolian soil. The wine produced from this soil had improved chroma and tone and higher-quality phenols. The grapes grown on the sierozem soil had the highest total phenol and tannin contents, which affected the wine composition. The grapes grown on the irrigation silting soil had higher acidities, but the remaining indices were lower. In addition, the grapes grown on the aeolian soil resulted in wines with better chroma and aroma. The sierozem soil was beneficial for the formation of wine tannins and phenols and significantly affected the wine composition. The quality of the grapes from the irrigation silting soil was relatively low, resulting in lower-quality wine.

Effect of extrusion cooking on the physicochemical properties, resistant starch, phenolic content and antioxidant capacities of green banana flour.

PubMed

Sarawong, Chonthira; Schoenlechner, Regine; Sekiguchi, Ken; Berghofer, Emmerich; Ng, Perry K W

2014-01-15

Green banana flour was extruded through a co-rotating twin-screw extruder with constant barrel temperature. The objectives of this study were to determine the effect of extrusion cooking variables (feed moisture, FM, 20% and 50%; screw speed, SS, 200 and 400rpm) and storing of the extruded flours at 4°C for 24h on the physicochemical properties, resistant starch (RS), pasting properties and antioxidant capacities. Extrusion cooking at higher FM and lower SS increased the amylose content, which was expressed in highest RS content. Water adsorption index (WAI) and pasting properties were increased, while water solubility index (WSI), total phenolic content (TPC) and antioxidant activities (FRAP, ABTS(+), DPPH) in free and bound phenolics were decreased compared to the other extruded samples. Storing the extruded flours at 4°C for 24h prior to oven drying was the main factor leading to a further increase in the content of amylose, RS, TPC and WSI values, as well as pasting properties - in particular peak viscosity. Compared to native banana flour, extrusion cooking caused significant changes in all studied properties of the extruded flours, except for soluble DF and antioxidant capacity (ABTS(+) and DPPH) of bound phenolics. Copyright © 2013 Elsevier Ltd. All rights reserved.

Further Insights on the Chemical Structure of Humic Substances (HS) and Chromophoric Dissolved Organic Matter (CDOM) in Relation to their Optical/Chemical Properties

NASA Astrophysics Data System (ADS)

Del Vecchio, R.; Schendorf, T. M.; Koech, K.; Blough, N. V.

2016-02-01

HS have been studied extensively over the last decades, yet the structural basis of their optical properties is still highly debated. Aromatic ketones, aldehydes and quinones along with carboxylic groups and phenolic moieties are significant constituents of HS, however their contribution to the optical properties has only recently been investigated. Chemical manipulation of selected functional groups thus represents an extremely promising approach to highlight the contribution of such groups to the HS (and CDOM) optical properties. Chemical reduction (and re-oxidation) along with pH titrations are employed herein to assess the relative contribution of aromatic ketones/aldehydes/quinones and carboxylic groups/phenolic moieties, respectively to the optical properties of HS (and CDOM). Results indicate that (a) the contribution of quinones to HS absorption and fluorescence is minor (or nil), while that of aromatic ketones (and aldehydes) is significant; (b) phenolic groups contribute more than carboxylic acids to the HS optical properties; (c) the effects of borohydride reduction and pH on the long-wavelength absorption and fluorescence is consistent with charge-transfer interactions between carbonyl and phenolic groups (as well as aromatic carboxylic acids, but to a smaller extent). Results will be presented within the context of our proposed charge-transfer model.

Synthesis and characterization of catalysts for the selective transformation of biomass-derived materials

NASA Astrophysics Data System (ADS)

Ghampson, Isaac Tyrone

The experimental work in this thesis focuses on generating catalysts for two intermediate processes related to the thermal conversion of lignocellulosic biomass: the synthesis and characterization of mesoporous silica supported cobalt catalysts for the Fischer-Tropsch reaction, and an exploration of the reactivity of bulk and supported molybdenum-based nitride catalysts for the hydrodeoxygenation (HDO) of guaiacol, a lignin model compound. The first section of the work details the synthesis of a series of silica-supported cobalt Fischer-Tropsch catalysts with pore diameters ranging from 2-23 nm. Detailed X-ray diffraction measurements were used to determine the composition and particle diameters of the metal fraction, analyzed as a three-phase system containing Cofcc, Cohcp and CoO particles. Catalyst properties were determined at three stages in catalyst history: (1) after the initial calcination step to thermally decompose the catalyst precursor into Co3O4, (2) after the hydrogen reduction step to activate the catalyst to Co and (3) after the FT reaction. From the study, it was observed that larger pore diameters supported higher turnover frequency; smaller pore diameters yielded larger mole fraction of CoO; XRD on post-reduction and post-FTS catalyst samples indicated significant changes in dispersivity after reduction. In the next section, the catalytic behaviors of unsupported, activated carbon-, alumina-, and SBA-15 mesoporous silica-supported molybdenum nitride catalysts were evaluated for the hydrodeoxygenation of guaiacol (2-methoxy phenol) at 300°C and 5 MPa. The nitride catalysts were prepared by thermal decomposition of bulk and supported ammonium heptamolybdate to form MoO 3 followed by nitridation in either flowing ammonia or a nitrogen/hydrogen mixture. The catalytic properties were strongly affected by the nitriding and purging treatment as well as the physical and chemical properties of support. The overall reaction was influenced by the crystalline phase present in the catalyst, dispersion of molybdenum nitride/oxynitride, and the porosity of the support. The hydrodeoxygenation of guaiacol followed two proposed reaction pathways: demethylation (DME) of guaiacol to form catechol, followed by dehydroxylation to form phenol; or a direct demethoxylation (DMO) to form phenol. The selectivity of the reaction was expressed in terms of the phenol/catechol ratio. Phenol was the predominant product for all the catalysts studied, except for the alumina-supported catalysts (an effect of the alumina support). The results from this thesis are encouraging for the application of Mo nitride based catalysts for hydrodeoxygenation of whole pyrolysis oil.

Chemical characterization of some aerobic liquids in CELSS

NASA Technical Reports Server (NTRS)

Madsen, Brooks C.

1993-01-01

Untreated aqueous soybean and wheat leachate and aerobically treated wheat leachate prepared from crop residues that are produced as a component of the Controlled Ecological Life Support System program designed to support long duration space missions were compared, and a general chemical characterization was accomplished. Solid phase extraction and high performance liquid chromatography were used to accomplish comparisons based on chromatographic and ultraviolet absorption properties of the components that are present. Specific compounds were not identified; however, general composition related to the initial presence of phenol-like compounds and their disappearance during aerobic treatment was explored.

Phenolic composition of basil plants is differentially altered by plant nutrient status and inoculation with mycorrhizal fungi

USDA-ARS?s Scientific Manuscript database

Quality of basil plants (Ocimum basilicum) used in certain fresh and dry products is a function of its production of secondary metabolites, including phenolic compounds. Nutrient availability, particularly phosphorus (P), can alter plant production of secondary metabolites, and root infection by arb...

Facile synthesis of hierarchical porous VOx@carbon composites for supercapacitors.

PubMed

Zhao, Chunxia; Cao, Jinqiao; Yang, Yunxia; Chen, Wen; Li, Junshen

2014-08-01

Hierarchical or micro-nano structured porous VOx@carbon composites were synthesized by a one-step method using phenolic resin as the carbon precursor and ammonium metavanadate as the source of vanadium oxides. The effects of the vanadium source loading on the microstructure and electrochemical properties of the composites were investigated. X-ray diffraction results showed that as the vanadium oxides source loading increased, vanadium oxides in the composites changed oxidation states from V2O3 to mixed states of V2O3 and VO2. Electrochemical test results indicated that the micro-nano porous structure of the composites could facilitate the ion diffusion in the rich porous structure and then promote the electrochemical reaction. More importantly, we found that vanadium oxides greatly enhanced the electrochemical performance of the materials, due to the faradic capacitance generated from vanadium oxide nanoparticles. A maximum specific capacitance of 171 F/g was obtained from VOx@carbon composite with vanadium loading of ∼44 wt%. Further increasing the VOx loading over this fraction was not beneficial. Our results suggested that hierarchical porous VOx@carbon composites were promising candidates for supercapacitor applications. Copyright © 2013 Elsevier Inc. All rights reserved.

Phenolic composition and mouthfeel characteristics resulting from blending Chilean red wines.

PubMed

Cáceres-Mella, Alejandro; Peña-Neira, Alvaro; Avilés-Gálvez, Pamela; Medel-Marabolí, Marcela; Del Barrio-Galán, Rubén; López-Solís, Remigio; Canals, Joan Miquel

2014-03-15

The blending of wine is a common practice in winemaking to improve certain characteristics that are appreciated by consumers. The use of some cultivars may contribute phenolic compounds that modify certain characteristics in blended wines, particularly those related to mouthfeel. The aim of this work was to study the effect of Carménère, Merlot and Cabernet Franc on the phenolic composition, proanthocyanidin profile and mouthfeel characteristics of Cabernet Sauvignon blends. Significant differences in chemical composition were observed among the monovarietal wines. Separation using Sep-Pak C₁₈ cartridges revealed differences in the concentration but not in the proportion of various proanthocyanidins. Blending reduced polyphenol concentration differences among the various monovarietal wines. Although no major overall differences were observed after blending the monovarietal wines, this oenological practice produced clear differences in mouthfeel characteristics in such a way that the quality of the perceived astringency was different. This study showed that the use of a particular wine variety (Cabernet Sauvignon) in a higher proportion in wine blending produced blends that were less differentiable from the monovarietal wine, owing to a suppression effect, producing an apparent standardization of the wines regarding chemical composition. © 2013 Society of Chemical Industry.

Exploratory Development of Corrosion Inhibiting Primers

DTIC Science & Technology

1977-07-01

Phenolic Hardener From previous studies, phenol formaldehyde resins of the novolac (two-step) type have given superior properties when used to cure epoxy...novolacs and three resole (one-step) type phenol- formaldehyde resins which also perform as epoxide curing agents. First, Model #1, as de;crihed in Section...results. Varcum 4326 resin was chosen at this stage for further use with the model systems. It is a low molecular weight phenol- formaldehyde resin used

Experimental determination of ablation vapor species from carbon phenolic heat-shield materials

NASA Technical Reports Server (NTRS)

Lincoln, K. A.

1981-01-01

The relative concentrations of vapors produced from carbon phenolic composites under thermal loadings approximating those expected at peak heating during vehicle entry into the atmospheres of the outer planets have been determined. The technique of vaporizing the surface of bulk samples by laser irradiation while measuring in situ the vapor species by mass spectrometry is described. Results show that vapor composition varies with irradiance level and with depth of heating (or extent of pyrolysis). Attempts are made to compare these experimental results with the theoretical predictions from computer codes.

UHPLC-MS/MS phenolic profiling and in vitro antioxidant activities of Inula graveolens (L.) Desf.

PubMed

Silinsin, Muzaffer; Bursal, Ercan

2018-06-01

Inula graveolens (L.) Desf. is an annual aromatic herb which has various uses on alternative medicine in many region of the world. In this study, antioxidant activities of ethanol and water extracts of the plant leaves were determined by in vitro DPPH method and phenolic composition of the plant sample was determined by LC-MS/MS analysis. The results showed that chlorogenic acid, quinic acid, hyperoside, protocatechuic acid and quercetin were the major phenolic compounds among the 27 standard compounds. The significant antioxidant capacity of the plant might be related with the high abundance of phenolic compounds.

Fungus Resistance of Plastics

DTIC Science & Technology

1951-08-17

Phenolic Phenolic Phenolic Phe-nolle Genera^.’ General General Electrical Electrical! Punching Mechanical General Electrical Fine Machin ...spores» The resulting separate suspensions were mixed to obtain a composite : spore suspension ~för"üse in inocüla ting the test specimens© 79...7 {SQKT33SI3SDJ fltttg*.8..«t.J56 FÜtfOOS BIBlSTikÄ C£ HäST’Iö LAMINATS (EüHigjiTy EXBöSTJSB; METHOD JL-.-- Ör&ie 5 - 11G

Determination of the floral origin of some Romanian honeys on the basis of physical and biochemical properties

NASA Astrophysics Data System (ADS)

Cimpoiu, Claudia; Hosu, Anamaria; Miclaus, Vasile; Puscas, Anitta

The aim of this study was to determine the physical and biochemical properties of some Romanian honeys in order to discriminate between their floral origins. The evaluated properties were total phenolic content, total protein content, total free amino acids content, color intensity (ABS450), pH, ash content, antioxidant activity. Twenty-six commercial honeys from six types of flowers (acacia, sunflower, forest, polyfloral, lime and Sea Buckthorn) were investigated. All samples showed considerable variations with reference to their properties. The properties values were in the range of approved limits (according to EU legislation). The total phenolic, total protein and total free amino acids contents and color intensity varied considerably. Similarly, forest honey had the highest antioxidant activity while the lowest was found in acacia honey. Correlation between the floral origin of honeys and the physical and biochemical properties, respectively, was observed. Moreover, this study demonstrates remarkable variation in DPPH scavenging activity and content of total phenols in honey, depending on its botanic source.

Profiling and quantification of phenolic compounds in Camellia seed oils: Natural tea polyphenols in vegetable oil.

PubMed

Wang, Xiaoqin; Zeng, Qiumei; Del Mar Contreras, María; Wang, Lijuan

2017-12-01

In Asia, tea seed oils (seed oils from Camellia oleifera, C. chekiangoleosa, and C. sinensis) are used in edible, medicinal, and cosmetic applications. However, these oils differ in their fatty acid contents, and there is little known about their phenolic compounds. Here we analyzed the phenolic compounds of seed oils from three species gathered from 15 regions of China. Twenty-four phenolic compounds were characterized by HPLC-Q-TOF-MS, including benzoic acids (6), cinnamic acids (6), a hydroxyphenylacetic acid, flavanols (4), flavonols (3), flavones (2), and dihydroflavonoids (2). Some of these phenolic compounds had not previously been reported from C. sinensis (20), C. oleifera (15), and C. chekiangoleosa (24) seed oils. Quantification was done by HPLC-QqQ-MS using 24 chemical standards. The total concentrations in the studied samples ranged from 20.56 to 88.56μg/g. Phenolic acids were the most abundant class, accounting for 76.2-90.4%, with benzoic acid, found at up to 18.87μg/g. The concentration of catechins, typical of tea polyphenols, ranged between 2.1% and 9.7%, while the other flavonoids varied from 4.2% to 17.8%. Although the cultivation region affected the phenolic composition of the Camellia seed oils, in our hierarchical clustering analysis, the samples clustered according to species. The phenolic composition of the seed oils from C. oleifera and C. chekiangoelosa were similar. We found that the phenolic categories in Camellia seed oils were similar to tea polyphenols, thereby identifying a source of liposoluble tea polyphenols and potentially accounting for some of the reported activities of these oils. In addition, this work provides basic data that allows distinction of various Camellia seed oils, as well as improvements to be made in their quality standards. Copyright © 2017 Elsevier Ltd. All rights reserved.

Phenolic profile and fermentation patterns of different commercial gluten-free pasta during in vitro large intestine fermentation.

PubMed

Rocchetti, Gabriele; Lucini, Luigi; Chiodelli, Giulia; Giuberti, Gianluca; Gallo, Antonio; Masoero, Francesco; Trevisan, Marco

2017-07-01

The fate of phenolic compounds, along with short-chain fatty acids (SCFAs) production kinetics, was evaluated on six different commercial gluten-free (GF) pasta samples varying in ingredient compositions, focussing on the in vitro faecal fermentation after the gastrointestinal digestion. A general reduction of both total phenolics and reducing power was observed in all samples, together with a substantial change in phenolic profile over 24h of faecal fermentation, with differences among GF pasta samples. Flavonoids, hydroxycinnamics and lignans degraded over time, with a concurrent increase in low-molecular-weight phenolic acids (hydroxybenzoic acids), alkylphenols, hydroxybenzoketones and tyrosols. Interestingly, discriminant analysis also identified several alkyl derivatives of resorcinol as markers of the changes in phenolic profile during in vitro fermentation. Furthermore, degradation pathways of phenolics by intestinal microbiota have been proposed. Considering the total SCFAs and butyrate production during the in vitro fermentation, different fermentation kinetics were observed among GF pasta post-hydrolysis residues. Copyright © 2017 Elsevier Ltd. All rights reserved.

Optimisation of Microwave-Assisted Extraction of Pomegranate (Punica granatum L.) Seed Oil and Evaluation 
of Its Physicochemical and Bioactive Properties

PubMed Central

Çavdar, Hasene Keskin; Gök, Uğur; Göğüş, Fahrettin

2017-01-01

Summary Pomegranate seed oil was extracted in a closed-vessel high-pressure microwave system. The characteristics of the obtained oil, such as fatty acid composition, free fatty acidity, total phenolic content, antioxidant activity and colour, were compared to those of the oil obtained by cold solvent extraction. Response surface methodology was applied to optimise extraction conditions: power (176–300 W), time (5–20 min), particle size (d=0.125–0.800 mm) and solvent to sample ratio (2:1, 6:1 and 10:1, by mass). The predicted highest extraction yield (35.19%) was obtained using microwave power of 220 W, particle size in the range of d=0.125–0.450 mm and solvent-to-sample ratio of 10:1 (by mass) in 5 min extraction time. Microwave-assisted solvent extraction (MASE) resulted in higher extraction yield than that of Soxhlet (34.70% in 8 h) or cold (17.50% in 8 h) extraction. The dominant fatty acid of pomegranate seed oil was punicic acid (86%) irrespective of the extraction method. Oil obtained by MASE had better physicochemical properties, total phenolic content and antioxidant activity than the oil obtained by cold solvent extraction. PMID:28559737

Antioxidant activity of Syzygium cumini leaf gall extracts

PubMed Central

Eshwarappa, Ravi Shankara Birur; Iyer, Raman Shanthi; Subbaramaiah, Sundara Rajan; Richard, S Austin; Dhananjaya, Bhadrapura Lakkappa

2014-01-01

Introduction: Free radicals are implicated in several metabolic diseases and the medicinal properties of plants have been explored for their potent antioxidant activities to counteract metabolic disorders. This research highlights the chemical composition and antioxidant potential of leaf gall extracts (aqueous and methanol) of Syzygium cumini (S. cumini), which have been extensively used in traditional medications to treat various metabolic diseases. Methods: The antioxidant activities of leaf gall extracts were examined using diphenylpicrylhydrazyl (DPPH), nitric oxide scavenging, hydroxyl scavenging and ferric reducing power (FRAP) methods. Results: In all the methods, the methanolic extract showed higher antioxidant potential than the standard ascorbic acid. The presence of phenolics, flavonoids, phytosterols, terpenoids, and reducing sugars was identified in both the extracts. When compared, the methanol extract had the highest total phenolic and flavonoid contents at 474±2.2 mg of GAE/g d.w and 668±1.4 mg of QUE/g d.w, respectively. The significant high antioxidant activity can be positively correlated to the high content of total polyphenols/flavonoids of the methanol extract. Conclusion: The present study confirms the folklore use of S. cumini leaves gall extracts as a natural antioxidant and justifies its ethnobotanical use. Further, the result of antioxidant properties encourages the use of S. cumini leaf gall extracts for medicinal health, functional food and nutraceuticals applications. PMID:25035854

Corrosion Protection of Phenolic-Epoxy/Tetraglycidyl Metaxylediamine Composite Coatings in a Temperature-Controlled Borax Environment

NASA Astrophysics Data System (ADS)

Xu, Wenhua; Wang, Zhenyu; Han, En-Hou; Liu, Chunbo

2017-12-01

The failure behavior for two kinds of phenolic-epoxy/tetraglycidyl metaxylediamine composite coatings in 60 °C borax aqueous solution was evaluated using electrochemical methods (EIS) combined with scanning electron microscopy, confocal laser scanning microscope, water immersion test, and Raman spectrum. The main focus was on the effect of curing agent on the corrosion protection of coatings. Results revealed that the coating cured by phenolic modified aromatic amine possessed more compact cross-linked structure, better wet adhesion, lower water absorption (0.064 mg h-1 cm-2) and its impedance values was closed to 108 Ω cm2 after immersion for 576 h, while the coating cured by modified aromatic ring aliphatic amine was lower than 105 Ω cm2. The corrosion mechanism of the two coatings is discussed.

Absorption, Metabolic Stability, and Pharmacokinetics of Ginger Phytochemicals.

PubMed

Mukkavilli, Rao; Yang, Chunhua; Singh Tanwar, Reenu; Ghareeb, Ahmed; Luthra, Latika; Aneja, Ritu

2017-03-30

We have previously demonstrated promising anticancer efficacy of orally-fed whole ginger extract (GE) in preclinical prostate models emphasizing the importance of preservation of the natural "milieu". Essentially, GE primarily includes active ginger phenolics viz., 6-gingerol (6G), 8-gingerol (8G), 10-gingerol (10G), and 6-shogaol (6S). However, the druglikeness properties of active GE phenolics like solubility, stability, and metabolic characteristics are poorly understood. Herein, we determined the physicochemical and biochemical properties of GE phenolics by conducting in vitro assays and mouse pharmacokinetic studies with and without co-administration of ketoconazole (KTZ). GE phenolics showed low to moderate solubility in various pH buffers but were stable in simulated gastric and intestinal fluids, indicating their suitability for oral administration. All GE phenolics were metabolically unstable and showed high intrinsic clearance in mouse, rat, dog, and human liver microsomes. Upon oral administration of 250 mg/kg GE, sub-therapeutic concentrations of GE phenolics were observed. Treatment of plasma samples with β-glucuronidase (βgd) increased the exposure of all GE phenolics by 10 to 700-fold. Co-administration of KTZ with GE increased the exposure of free GE phenolics by 3 to 60-fold. Interestingly, when the same samples were treated with βgd, the exposure of GE phenolics increased by 11 to 60-fold, suggesting inhibition of phase I metabolism by KTZ but little effect on glucuronide conjugation. Correlating the in vitro and in vivo results, it is reasonable to conclude that phase II metabolism seems to be the predominant clearance pathway for GE phenolics. We present evidence that the first-pass metabolism, particularly glucuronide conjugation of GE phenolics, underlies low systemic exposure.

Flavonoids: hemisynthesis, reactivity, characterization and free radical scavenging activity.

PubMed

Es-Safi, Nour-Eddine; Ghidouche, Souhila; Ducrot, Paul Henri

2007-09-26

Phenolic compounds form one of the main classes of secondary metabolites. They display a large range of structures and they are responsible for the major organoleptic characteristics of plant-derived-foods and beverages, particularly color and taste properties and they also contribute to the nutritional qualities of fruits and vegetables. Phenolic compounds are also highly unstable compounds which undergo numerous enzymatic and chemical reactions during postharvest food storage and processing thus adding to the complexity of plant polyphenol composition. Among these compounds flavonoids constitute one of the most ubiquitous groups of all plant phenolics. Owing to their importance in food organoleptic properties and in human health, a better understanding of their structures, their reactivity and chemical properties in addition to the mechanisms generating them appears essential to predict and control food quality. The purpose of this work is an overview of our findings concerning the hemisynthesis, the reactivity and the enzymatic oxidation of some flavonoids and shed light on the mechanisms involved in some of these processes and the structures of the resulting products. The free radical scavenging activity of some of the synthesized compounds is also presented and a structure-activity relationship is discussed. The first part of this review concerns the synthesis and structural characterization of modified monomeric flavanols. The use of these compounds as precursor for the preparation of natural and modified dimeric procyanidin derivatives was then explored through different coupling reactions. The full characterization of the synthesized compounds was achieved by concerted use of NMR and ESI-MS techniques. The free radical scavenging activity of some of the synthesized compounds was investigated. The second part of this review concerns the enzymatic oxidation of several flavonols by Trametes versicolor laccase. Most of the major oxidation products have been isolated as pure compounds and their structures unambiguously established through spectroscopic methods. Correlation between the structure of the oxidation product and the substitution pattern of the starting materials allows mechanistic features of this transformation to be elucidated.

Chia Oil Extraction Coproduct as a Potential New Ingredient for the Food Industry: Chemical, Physicochemical, Techno-Functional and Antioxidant Properties.

PubMed

Fernández-López, Juana; Lucas-González, Raquel; Viuda-Martos, Manuel; Sayas-Barberá, Estrella; Pérez-Alvarez, José Angel

2018-06-01

The aim of this work was to characterize the coproduct obtained from chia oil production (cold-pressing) with a view to its possible application in new food product development. For this characterization, the following determinations were made: proximate composition, physicochemical analysis, techno-functional properties, total phenolic and flavonoid content, polyphenolic profile and antioxidant capacity (using four different methods). Chia coproduct showed significantly higher levels of proteins and total dietary fiber and lower levels of fats than chia seeds, pointing to the promising nature of this coproduct as an ingredient of food formulations since it remains a source of high biological value proteins and total dietary fiber (as chia seeds themselves) but with a lower energy value. This chia coproduct presents similar techno-functional properties to the original chia seeds and significantly higher levels of polyphenolic compounds and, consequently, higher antioxidant activity.

Identification and Quantification of Avenanthramides and Free and Bound Phenolic Acids in Eight Cultivars of Husked Oat ( Avena sativa L) from Finland.

PubMed

Multari, Salvatore; Pihlava, Juha-Matti; Ollennu-Chuasam, Priscilla; Hietaniemi, Veli; Yang, Baoru; Suomela, Jukka-Pekka

2018-03-21

Finland is the second largest oat producer in Europe. Despite the existing knowledge of phenolics in oat, there is little information on the phenolic composition of oats from Finland. The aim of the study was to investigate the concentrations of free and bound phenolic acids, as well as avenanthramides in eight Finnish cultivars of husked oat ( Avena sativa L.). Seven phenolic acids and one phenolic aldehyde were identified, including, in decreasing order of abundance: p-coumaric, ferulic, cinnamic, syringic, vanillic, 2,4-dihydroxybenzoic, and o-coumaric acids and syringaldehyde. Phenolic acids were mostly found as bound compounds. Significant varietal differences ( p < 0.05) were observed in the cumulative content of phenolic acids, with the lowest level found in cv. 'Viviana' (1202 ± 52.9 mg kg -1 ) and the highest in cv. 'Akseli' (1687 ± 80.2 mg kg -1 ). Avenanthramides (AVNs) 2a, 2p, and 2f were the most abundant. Total AVNs levels ranged from 26.7 ± 1.44 to 185 ± 12.5 mg kg -1 in cv. 'Avetron' and 'Viviana', respectively.

Hydrogen Bonding-Mediated Microphase Separation during the Formation of Mesoporous Novolac-Type Phenolic Resin Templated by the Triblock Copolymer, PEO-b-PPO-b-PEO

PubMed Central

Chu, Wei-Cheng; Chiang, Shih-Fan; Li, Jheng-Guang; Kuo, Shiao-Wei

2013-01-01

After blending the triblock copolymer, poly(ethylene oxide-b-propylene oxide-b-ethylene oxide) (PEO-b-PPO-b-PEO) with novolac-type phenolic resin, Fourier transform infrared spectroscopy revealed that the ether groups of the PEO block were stronger hydrogen bond acceptors for the OH groups of phenolic resin than were the ether groups of the PPO block. Thermal curing with hexamethylenetetramine as the curing agent resulted in the triblock copolymer being incorporated into the phenolic resin, forming a nanostructure through a mechanism involving reaction-induced microphase separation. Mild pyrolysis conditions led to the removal of the PEO-b-PPO-b-PEO triblock copolymer and formation of mesoporous phenolic resin. This approach provided a variety of composition-dependent nanostructures, including disordered wormlike, body-centered-cubic spherical and disorder micelles. The regular mesoporous novolac-type phenolic resin was formed only at a phenolic content of 40–60 wt %, the result of an intriguing balance of hydrogen bonding interactions among the phenolic resin and the PEO and PPO segments of the triblock copolymer. PMID:28788378

Antimicrobial, Antioxidant, Anti-Inflammatory, and Cytotoxic Activities of Propolis from the Stingless Bee Tetragonisca fiebrigi (Jataí).

PubMed

Campos, Jaqueline Ferreira; Dos Santos, Uilson Pereira; da Rocha, Paola Dos Santos; Damião, Marcio José; Balestieri, José Benedito Perrella; Cardoso, Claudia Andrea Lima; Paredes-Gamero, Edgar Julian; Estevinho, Leticia Miranda; de Picoli Souza, Kely; Dos Santos, Edson Lucas

2015-01-01

Propolis from stingless bees Tetragonisca fiebrigi found in Brazil is used in folk medicine by their nutritional and therapeutic properties. However, there are no scientific records evidencing such properties. The present study was designed to investigate the chemical composition and the biological properties of propolis from T. fiebrigi. For this, the chemical composition of the ethanol extract of propolis (EEP) was determined by GC-MS and presented phenolic compounds, alcohol, and terpenes as its major class compounds. The antimicrobial activity was accessed in gram-positive and gram-negative bacteria and in fungi, isolated from different biological fluids and reference strains. The EEP was active against all microorganisms and showed antioxidant activity by scavenging free radicals, inhibiting hemolysis and lipid peroxidation in human erythrocytes incubated with an oxidizing agent. The anti-inflammatory potential of the EEP was confirmed by inhibition of the hyaluronidase enzyme. The cytotoxic activity was concentration-dependent against K562 cells, with a predominance of death by necrosis. Taken together, these results show that propolis from T. fiebrigi has important therapeutic activities, which suggest its potential application in the pharmaceutical industry, as well as in health foods, beverages, and nutritional supplements.

Flight-and ground-test evaluation of pyrrone foams

NASA Technical Reports Server (NTRS)

Mclain, A. G.; Kelliher, W. C.

1972-01-01

Two Pyrrone materials, pure Pyrrone foam with a density of 481 kg/cu m and hollow glass microsphere-Pyrrone composite with a density of 962 kg/cu m, were tested in the Langley 20-inch hypersonic arc heated tunnel at pressure levels from 0.06 to 0.27 atm and heating rates from 1.14 to 11.4 MW/sq m. The 481-kg/cu m Pyrrone foam was also flight tested as an experiment aboard a Pacemaker test vehicle. The results of the ground tests indicated that the thermal effectiveness of the 481-kg/cu m Pyrrone foam was superior to the 962-kg/cu m glass sphere-Pyrrone composite. The 481-kg/cu m Pyrrone foam had approximately one-half the thermal effectiveness of low density phenolic nylon. The 481-kg/cu m Pyrrone foam experienced random mechanical char removal over the entire range of test conditions. Char thermal property inputs for an ablation computer program were developed from the ground test data of the 481-kg/cu m Pyrrone foam. The computer program using these developed char thermal properties, as well as the measured uncharred material properties, adequately predicted the in-depth temperature histories measured during the Pacemaker flight.