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Brezani, Viliam, Karel Smejkal, Jan Hosek et Veronika Tomasova. « Anti-inflammatory Natural Prenylated Phenolic Compounds - Potential Lead Substances ». Current Medicinal Chemistry 25, no 10 (9 avril 2018) : 1094–159. http://dx.doi.org/10.2174/0929867324666170810161157.
Texte intégralRésumé :
Background: Natural phenolics are secondary plant metabolites, which can be divided into several categories with the common structural feature of phenolic hydroxyl. The biological activity of phenolics is often modified and enhanced by prenylation by prenyl and geranyl; higher terpenoid chains are rare. The type of prenyl connection and modification affects their biological activity. Objective: This review summarizes information about prenylated phenols and some of their potential sources, and provides an overview of their anti-inflammatory potential in vitro and in vivo. Method: The literature search was performed using SciFinder and keywords prenyl, phenol, and inflammation. For individual compounds, an additional search was performed to find information about further activities and mechanisms of effects. Result: We summarized the effects of prenylated phenolics in vitro in cellular or biochemical systems on the production and release of inflammation-related cytokines; their effects on inhibition of cyclooxygenases and lipoxygenases; the effects on production of nitric oxide, antiradical and antioxidant activity; and the effect on the inhibition of the release of enzymes and mediators from neutrophils, mast cells and macrophages. The information about the antiphlogistic potential of prenylated phenolics is further supported by a review of their action in animal models. Conclusion: Almost 400 prenylated phenols were reviewed to overview their antiinflammatory effect. The bioactivity of several prenylated phenols was confirmed also using in vivo assays. A pool of natural prenylated phenols represents a source of inspiration for synthesis, and prenylated phenols as components of various medicinal plants used to combat inflammation could be their active principles.
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Shi, Zhen Jing, Meng Xiang Fang, Chun Guang Zhou, Shu Rong Wang et Zhong Yang Luo. « Studies on the Extraction of Phenols from Coal Tar Produced in Multi-Generation System ». Advanced Materials Research 347-353 (octobre 2011) : 673–77. http://dx.doi.org/10.4028/www.scientific.net/amr.347-353.673.
Texte intégralRésumé :
Isolation of phenols from the middle oil fraction(170-230°C) of tar produced in the multi-cogeneration system has been investigated for the purpose of recovering valuable pure phenols, such as phenol, cresols, xylenol and ethyl-phenol. Phenolic compounds were separated from the middle oil by liquid-liquid extraction using alkali and sulfuric acid. The yield of phenolic fraction from the middle oil (170-230°C) is up to 37%, which is much higher compared with those of metallurgical coke plants. Chromatography-mass spectrometry was used to analyse phenolic compounds. The result shows that the phenol content is less than 2%, and main compounds are cresol(14%), xylenol(20%) . Phenols of the middle oil fraction(230-280°C) was also analysed, which main contain methyl naphthol(20%).
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Muráriková, A., K. Kaffková, S. Raab et J. Neugebauerová. « Evaluation of content of phenolics in Salvia species cultivated in South Moravian Region / Hodnotenie obsahu fenolov vo vybraných druhoch rodu Salvia L. pestovaných v Juhomoravskom kraji ». Acta Facultatis Pharmaceuticae Universitatis Comenianae 62, s9 (1 juin 2015) : 18–22. http://dx.doi.org/10.1515/afpuc-2015-0007.
Texte intégralRésumé :
Abstract In this study, total phenolic content (TPC) and rosmarinic acid (RA) of 37 samples sage (Salvia L.) of extracts were determined using spectrophotometric methods. The amount of total phenols was analysed with Folin-Ciocalteu reagents. Gallic acid was used as a standard compound and the total phenols were expressed as mg.g−1 gallic acid equivalents of dried plant material. The values of the extracts displayed substantial differences. All of the investigated species except Salvia jurisicii (990.79 mg GAE. g−1 d.w.) exhibited higher content of phenolics. Among the studies, species demonstrated the highest content of phenol, followed in sequence by Salvia tomentosa, Salvia fruticosa, Salvia triloba, Salvia officinalis ‘Extrakta’, Salvia officinalis. TPC varied from 990.79 to 4459.88 mg GAE. g−1 d.w. in the extracts. The total amount of RA was between 0.88 and 8.04% among species. Salvia tomentosa, Salvia verticillata and Salvia officinalis ‘Extrakta’ had the highest content of RA. The high content of phenolic compounds indicated that these compounds contribute to the antioxidant activity.
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Mikulic Petkovsek, M., F. Stampar et R. Veberic. « Seasonal changes in phenolic compounds in the leaves of scab-resistant and susceptible apple cultivars ». Canadian Journal of Plant Science 89, no 4 (1 juillet 2009) : 745–53. http://dx.doi.org/10.4141/cjps08202.
Texte intégralRésumé :
Leaf samples were collected from apple varieties susceptible and resistant to apple scab [Venturia inaequalis (Cke.) Wint.] from June to September for 2 yr between 2005 and 2006. These were analyzed for phenolic compounds, using high-performance liquid chromatography (HPLC). In the apple leaves, the following hydroxycinnamic acids were detected: chlorogenic, caffeic and p-coumaric acids; the following dihydrochalcone: phloridzin, and the following flavonoids: epicatechin, catechin, rutin and quercitrin. The total of phenolic compounds in apple leaves was determined spectrophotometrically, using the Folin-Ciocalteu method. During the growing season, the content of phenolic compounds changed and was related to the physiological stage of the tissue and cultivar used. Each phenolic compound had its own curve of seasonal changes in concentration. In 2005 there was no significant change in total phenols during the growing season. In 2006, their content changed significantly during the growing season; statistically the highest content of total phenols was found in the leaves in August. Total phenols as well as single phenolics were statistically higher in resistant than in susceptible apple varieties for both years.Key words: Malus × domestica Borkh., leaves, phenolic compounds, seasonal changes, Venturia inaequalis (Cke.) Wint., resistance
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Sithole, Bishop B., et David T. Williams. « Halogenated Phenols in Water at Forty Canadian Potable Water Treatment Facilities ». Journal of AOAC INTERNATIONAL 69, no 5 (1 septembre 1986) : 807–10. http://dx.doi.org/10.1093/jaoac/69.5.807.
Texte intégralRésumé :
Abstract Samples of raw and treated water were collected once in each of 3 seasons at 40 potable water treatment plants across Canada and were analyzed for phenol and 33 halogenated phenolic compounds including chlorophenols, bromophenols, bromochlorophenols, and chloroguaiacols. Eighteen of the compounds were not found at any treatment plant; phenol and each of the remaining halogenated phenols were found in at least 1 sample. Pentachlorophenol was the only halogenated phenolic compound found in more than 20% of the raw water samples in the fall and winter samples at levels up to 53 ng/L with mean values of 1.9 and 2.8 ng/L, respectively. No halogenated phenols were detected in raw water summer samples. The halogenated phenols found most frequently in treated water samples were 4-chloro-, 2,4-dichloro-, 2,4,6- trichloro-, and bromodichlorophenols. Mean values were less than 15 ng/L and maximum values seldom exceeded 100 ng/L. Most of the positive values for the treated water samples were found at 8 of the 40 treatment plants but no correlations could be found between halogenated phenol levels and raw water type, treatment process, or chemical dosages.
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van Gorsel, Hendrik, et Adel A. Kader. « PHENOLIC METABOLISM AND INTERNAL BREAKDOWN (CHILLING INJURY) OF PEACH FRUIT ». HortScience 25, no 11 (novembre 1990) : 1356H—1357. http://dx.doi.org/10.21273/hortsci.25.11.1356.
Texte intégralRésumé :
Internal breakdown (IB) is the limiting factor in the storage and postharvest handling of stone fruits. The symptoms of IB appear when fruits are kept for prolonged periods at temperatures below 10C and include leatheriness, mealiness, browning and bleeding of the flesh, and failure to ripen normally. We investigated the changes in phenolic compounds associated with IB of stone fruits. Twenty-eight phenolic compounds were separated by HPLC. Ten of these components were significantly affected by chilling temperatures. The concentration of six phenols changed in response to ripening after chilling temperatures, parallel to the appearance of IB symptoms. Most phenols showed a concentration gradient from the inside to the outside of the fruit, Comparison between peach cultivars showed characteristic differences in phenol metabolism during ripening. In both cultivars the most predominant phenol, chlorogenic acid, showed little change in concentration during storage. The structure of key phenolic compounds will be determined in order to elucidate the biochemical relationship between the phenols and the related enzymes. In this respect, a method was developed to detect phenylalanine ammonia-lyase (PAL) activity in peach fruit.
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Martín, Carlos, Helene B. Klinke, Marcelo Marcet, Luis García, Ena Hernández et Anne Belinda Thomsen. « Study of the phenolic compounds formed during pretreatment of sugarcane bagasse by wet oxidation and steam explosion ». Holzforschung 61, no 5 (1 août 2007) : 483–87. http://dx.doi.org/10.1515/hf.2007.106.
Texte intégralRésumé :
Abstract The formation of phenolic compounds during pretreatment of sugarcane bagasse was investigated. Bagasse was pretreated by wet oxidation (WO) at 195°C during 15 min under either alkaline or acidic conditions and by steam explosion (STEX) at 205°C during 10 min. The total content of phenolic compounds in the prehydrolysates was determined spectrophotometrically. Under acidic and alkaline WO conditions, 3.8% (w/w) and 3% phenols were found, respectively. STEX gave rise to 1.9% phenols. Individual phenols were identified by GC-MS. Phenylpropanoid derivatives, such as p-coumaric and ferulic acids, accounted for more than 50% of the phenols identified in STEX prehydrolysates. In WO prehydrolysates, on the other hand, phenols lacking the propanoid side chain were predominant. Of the latter, p-hydroxybenzaldehyde was the most abundant phenol, with concentrations of 0.27% (acidic conditions) and 0.15% (alkaline conditions). As expected, high concentrations of oxidised compounds were generally observed in WO prehydrolysates, such as carboxylic acids, aldehydes and ketones. This is a true reflection of the oxidative conditions during WO pretreatment.
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Kochana, Jolanta, Juliusz Adamski et Andrzej Parczewski. « A Critical View on the Phenol Index as a Measure of Phenol Compounds Content in Waters. Application of a Biosensor ». Ecological Chemistry and Engineering S 19, no 3 (1 janvier 2012) : 383–91. http://dx.doi.org/10.2478/v10216-011-0028-5.
Texte intégralRésumé :
A Critical View on the Phenol Index as a Measure of Phenol Compounds Content in Waters. Application of a BiosensorPhenol index is considered as an important indicator of water purity and quality. Usually phenol index is determined by a spectrophotometric method the calibration being based on phenol standards. Unfortunately, the absorptivities of different phenols compounds differ from each other. This leads to significant uncertainty concerning content of phenols in water. It is shown that the same shortage of the phenol index appears also if it is determined using an amperometric biosensor based on tyrosinase. The sensitivity of the biosensor response to four phenol compounds: phenol, catechol, 3-cresol and 4-chlorophenol was examined, as well as possible interactions between phenols, according to 24factorial experiment. It was proved that individual phenols affect phenol index independently from each other,ieno significant interaction between phenols was detected. However, sensitivity of the biosensor to different phenols is not the same. Relationship between phenol index and concentrations of phenols in water is discussed.
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Smith, Terrence J., Ross H. Wearne et Adrian F. A. Wallis. « Characteristics of the Chlorinated Organic Substances in Filtrates from Bleaching of Oxygen-Delignified Eucalypt Kraft Pulp ». Water Science and Technology 29, no 5-6 (1 mars 1994) : 61–71. http://dx.doi.org/10.2166/wst.1994.0702.
Texte intégralRésumé :
Oxygen-delignified kraft pulps from mature and young eucalypt woods were bleached with sequences involving chlorine (C), chlorine dioxide (D) and alkali-oxygen (EO). The bleaching filtrates were analysed for chlorinated organic compounds by gas chromatography with the use of a mass selective detector. Chlorinated compounds found included a range of chlorinated phenols, neutral compounds, aliphatic acids and phenolic acids. A total of 41 chlorinated phenols were identified, mostly in the filtrates following chlorination {(EO)[C]} and only few in the (EO)[D] filtrates. 2-Chlorosyringaldehyde was the only significant chlorinated phenol obtained after D-prebleaching. There was no indication of differences in the types of chlorinated phenols obtained from the mature and young eucalypt samples, although there were higher levels of phenols in filtrates from the younger wood sample. The dominant chlorinated neutral compounds found in the filtrates were chloroform, chloroacetones and chlorodimethylsulfones. Most chloroform and chloroacetones were found in the C-stage filtrates, while chlorodimethylsulfones were found in both C and D-stage filtrates to the same extent. An abundant compound with probable molecular formula C5H3ClO3 was also in the neutral fraction. The chloroacetic acids were the only aliphatic acids detected and were found in all filtrates examined. A method for the analysis of chlorinated phenolic acids involving sequential acetylation and methylation of the extracts was devised. Three chlorinated phenolic acids were identified in the filtrates as their methyl ester acetates. The total amount of chlorinated compounds analysed was consistently higher in the young eucalypt sample than in the mature sample, and correlated well with the generic parameters AOX and EOX. High molar mass (HMM) solids prepared from the C(EO) bleaching filtrates by ultrafiltration had higher chlorine contents than those from the D(EO) bleaching filtrates. Apparent molecular mass distributions of the HMM solids determined by high performance size exclusion chromatography were dependent on the method of detection.
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Meza-Escalante, Edna R., Larissa Lepe-Martinié, Carlos Díaz-Quiroz, Denisse Serrano-Palacios, Luis H. Álvarez-Valencia, Ana Rentería-Mexía, Pablo Gortáres-Moroyoqui et Gabriela Ulloa-Mercado. « Capacity of Marine Microalga Tetraselmis suecica to Biodegrade Phenols in Aqueous Media ». Sustainability 14, no 11 (30 mai 2022) : 6674. http://dx.doi.org/10.3390/su14116674.
Texte intégralRésumé :
Phenolic compounds are toxic and dangerous to the environment and human health. Although the removal of phenols and their derivatives is very difficult, it has been achieved by applying some biological processes. The capacity of microalga to remove phenolic compounds has been demonstrated; however, few reports of the removal of these compounds in a mixture have been published. The removal of phenol, p-cresol and o-cresol was performed by batch kinetics at 50 and 100 mg L−1, and the simultaneous degradation of phenol, p-cresol and o-cresol was carried out in a mixture at 40 mg L−1 using the marine microalga Tetraselmis suecica. The kinetic study was carried out for 192 h. For concentrations of 50 mg L−1 and 100 mg L−1, phenolic compound consumption efficiencies greater than 100% and 85%, respectively, were obtained, and up to 73.6% removal in the mixture. The results obtained indicate that the marine microalga carries out a process of the oxidation of organic matter and phenolic compounds, mineralizing up to 31.4% to CO2 in the mixture. Biological treatments using the marine microalga T. suecica can be considered feasible to treat effluents with concentrations similar to those of the present study.
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Jia, Yong Hui. « Technical Study on Relationship between Terpene Phenolic Compounds and Health ». Advanced Materials Research 518-523 (mai 2012) : 529–32. http://dx.doi.org/10.4028/www.scientific.net/amr.518-523.529.
Texte intégralRésumé :
The hydroxy derivatives of aromatic hydrocarbons which have hydroxyl getup directly attached to the ring are called phenols. Small amounts of water dissolved in phenol lower the melting point to below the room temperature. This paper summarized the bioactivities and safety issues of Terpene Phenolic, and its functions, biosynthetic mechanisms, characteristics and clearing strategies of terpene phenolic compounds.
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Bisaillon, Jean-Guy, François Lépine, Réjean Beaudet et Michel Sylvestre. « Potential for carboxylation–dehydroxylation of phenolic compounds by a methanogenic consortium ». Canadian Journal of Microbiology 39, no 7 (1 juillet 1993) : 642–48. http://dx.doi.org/10.1139/m93-093.
Texte intégralRésumé :
An anaerobic consortium that carboxylated and dehydroxylated phenol to benzoate, and 2-cresol to 3-methylbenzoic acid, under methanogenic conditions was studied. Phenol induced this transformation activity. Addition of 4-hydroxypyridine or an increase in the concentration of proteose peptone to 0.5% (w/v) delayed the transformation. Phenol enhanced the rate of transformation of 2-cresol whereas 2-cresol delayed the transformation of phenol. Phenols with ortho-substitutions (chloro-, fluoro-, bromo-, hydroxyl-, amino-, or carboxyl-) were transformed to meta-substituted benzoic acids. However, meta- and para-substituted phenols (cresols, fluorophenols, and chlorophenols) were not transformed. Phenol was most rapidly metabolized, followed by catechol, 2-cresol, 2-fluorophenol, 2-aminophenol, 2-chlorophenol, 2-hydroxybenzoic acid, and 2-bromophenol. The consortium O-demethylated anisole to phenol and 2-methoxyphenol to catechol, and oxidized 2-hydroxybenzyl alcohol to 2-hydroxybenzoic acid. Aniline, 2-ethylphenol, 2-hydroxypyridine, 2-acetamidophenol, 2,6-dimethylphenol, 2-phenylphenol, and 1-naphthol were not metabolized.Key words: phenolic compounds, methanogenic consortium, carboxylation–dehydroxylation.
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Yang, Jian Qiong, Hai Liu, Lei Peng et Guo An Luo. « Study on Terpene Phenolic Compounds and its Health Effects ». Advanced Materials Research 1004-1005 (août 2014) : 924–27. http://dx.doi.org/10.4028/www.scientific.net/amr.1004-1005.924.
Texte intégralRésumé :
Hydroxy derivatives of aromatic hydrocarbons, have hydroxyl getup directly attached to the ring, which is called phenols. This paper study the bioactivities and safety issues of Terpene Phenolic and its functions, characteristics and clearing strategies of terpene phenolic compounds, so as its biosynthetic mechanisms. The results show that the small amounts of water dissolved in phenol lower the melting point to below the room temperature.
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Ezerskis, Z., et Z. Jusys. « Oxidation of chlorophenols on Pt electrode in alkaline solution studied by cyclic voltammetry, galvanostatic electrolysis, and gas chromatographymass spectrometry ». Pure and Applied Chemistry 73, no 12 (1 janvier 2001) : 1929–40. http://dx.doi.org/10.1351/pac200173121929.
Texte intégralRésumé :
Potentiodynamic investigations on a platinum electrode show that oxidation of phenol, monochlorophenols, dichlorophenols, 2,3,6-, 2,4,5-, 2,4,6-trichlorophenols, and pentachlorophenol in 1 M NaOH solution, containing 1 mM of phenols, proceeds in the potential region of Pt oxide formation. The oxidation rate of phenols decreases with the increase in the number of chlorine atoms in the benzene ring in the row: phenol > monochlorophenols > dichlorophenols > trichlorophenols > pentachlorophenol. The electrochemical stability of phenols, as studied using a cyclic voltammetry, depends on their chlorination degree and isomerism. Galvanostatic oxidation of 1 M NaOH solutions containing 1 mM of phenol, monochlorophenols, dichlorophenols, 2,3,6-, 2,4,5-, 2,4,6-trichlorophenols, and pentachlorophenol were carried out on a platinum electrode using 30 mA cm2 current density. The electrolysis of the solutions was performed in the course of 10 h, and concentration of phenols in the anolytes was monitored during oxidation. The concentration of phenolic compounds diminishes from 1 mM to 1050 mM during 45 h of electrooxidation and does not change during further galvanostatic oxidation. A decrease in concentration of phenols during galvanostatic electrolysis weakly depends on the isomerism and a chlorination degree of the compounds. A rapid decrease in concentration of studied phenols during the first 45 h of electrolysis and a nonselective oxidation of different chlorophenols suggest that the oxidation proceeds via electrochemically generated oxidants. Further decrease in concentration of phenols is rather small due to deactivation of the electrode as a result of polymerization of corresponding phenols and diffusion limitations.
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Lemma, Grehl, Zech, Mekonnen, Zech, Nemomissa, Bekele et Glaser. « Phenolic Compounds as Unambiguous Chemical Markers for the Identification of Keystone Plant Species in the Bale Mountains, Ethiopia ». Plants 8, no 7 (16 juillet 2019) : 228. http://dx.doi.org/10.3390/plants8070228.
Texte intégralRésumé :
: Despite the fact that the vegetation pattern and history of the Bale Mountains in Ethiopia were reconstructed using pollen, little is known about the former extent of Erica species. The main objective of the present study is to identify unambiguous chemical proxies from plant-derived phenolic compounds to characterize Erica and other keystone species. Mild alkaline CuO oxidation has been used to extract sixteen phenolic compounds. After removal of undesired impurities, individual phenols were separated by gas chromatography and were detected by mass spectrometry. While conventional phenol ratios such as syringyl vs. vanillyl and cinnamyl vs. vanillyl and hierarchical cluster analysis of phenols failed for unambiguous Erica identification, the relative abundance of coumaryl phenols (>0.20) and benzoic acids (0.05—0.12) can be used as a proxy to distinguish Erica from other plant species. Moreover, a Random Forest decision tree based on syringyl phenols, benzoic acids (>0.06), coumaryl phenols (<0.21), hydroxybenzoic acids, and vanillyl phenols (>0.3) could be established for unambiguous Erica identification. In conclusion, serious caution should be given before interpreting this calibration study in paleovegetation reconstruction in respect of degradation and underground inputs of soil organic matter.
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Duguet, J. P., B. Dussert, J. Mallevialle et F. Fiessinger. « Polymerization Effects of Ozone : Applications to the Removal of Phenolic Compounds from Industrial Wastewaters ». Water Science and Technology 19, no 5-6 (1 mai 1987) : 919–30. http://dx.doi.org/10.2166/wst.1987.0270.
Texte intégralRésumé :
Degradation of phenols by ozone has been extensively studied but the oxidative coupling pathway of ozone resulting in a phenol polymerization has not been largely investigated. Application of low ozone dose in solutions of 2.4 dichlorophenol and salicylic acid is characterized by the formation of high molecular compounds which are partially insoluble. Numerous polymers have been identified by gas chromatography coupled with mass spectrometry. Application of the polymerization effect of ozone to petrochemical and coking wastewaters containing phenols give similar results. In each case, phenolic compounds are efficiently removed, even if a large organic content is present. In the case of petrochemical wastewater, where phenols represent only 30% of TOC, the ozone effects are not sufficient to merit an ozonation step on the present treatment line. On the other hand, when phenols represent the greater part of the organics, as in coking wastewater, an important fraction of insoluble compounds, easily removed by filtration, are formed.
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Frías-Zepeda, M. Estela, et Martha Rosales-Castro. « Effect of extraction conditions on the concentration of phenolic compounds in Mexican oregano (Lippia graveolens Kunth) residues ». Revista Chapingo Serie Ciencias Forestales y del Ambiente 27, no 3 (31 août 2021) : 367–81. http://dx.doi.org/10.5154/r.rchscfa.2020.10.066.
Texte intégralRésumé :
Introduction: Mexican oregano (Lippia graveolens Kunth) leaves are marketed for use in food and for essential oil extraction. Phenolic compounds with antioxidant properties can be obtained from the residues (leaves without oil and stems) under appropriate extraction conditions. Objective: To evaluate the effect of extraction solvent and mass/volume ratio on phenolic compounds concentration and their antioxidant capacity in oregano residues. Materials and methods: Residual leaf (without oil) and stems of oregano were used to obtain extracts with 30, 50 and 80 % aqueous ethanol (ET30, ET50, ET80, respectively) and solvent mass/ volume ratios (1:10, 1:20 and 1:30). Yield in solids, total phenols concentration and flavonoids, and antioxidant capacity were evaluated in the extracts. Similarity analysis between extracts was performed by HPLC-DAD and the main phenols were identified by UPLC-MS. Results and discussion: Extract yields, phenol concentrations and flavonoids and antioxidant capacity for leaves were higher than for stems. The maximum concentration of phenols was obtained with ET80 and 1:30 ratio, which indicates better dissolution in ethanol than in water. The extracts ET50 and ET80 had chromatographic similarity of phenols in both residues; naringenin, taxifolin, eriodictyol, caffeic acid and luteolin were the major compounds. Conclusion: Ethanol-water concentrations and mass/solvent ratios are feasible for obtaining flavonoid and non-flavonoid phenolic compounds with antioxidant capacity from oil-free leaves and stems of oregano.
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Kalinowski, Andzrej, et Sławomir Bartkowiak. « Chromatographic analysis of phenol compounds in six natural populations of Anthyllis vulneraria (L.) ». Acta Societatis Botanicorum Poloniae 48, no 2 (2015) : 205–15. http://dx.doi.org/10.5586/asbp.1979.018.
Texte intégralRésumé :
Thin-layer chromatography was used to study the phenol composition in individual plants from six natural populations of <i>Anthyllis<i> collected from three distinct geographic regions of Poland. The results showed a variability of the phenols in the examined populations. The populations from Wielkopolska region proved to be most variable, showing the greatest number of phenols. The lowest number of the phenols studies was found in the Tatry populations. Each population showed its own particular spectrum of phenolic compounds. It was found that the populations originating from similar habitats showed more common spots than those from different regions. Populations from the Tatra region were found to differ most from the rest.
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Balahouane, Abdelghani Mounir, Mohamed Lakhdar Belfar, Yacine Moussaoui et Nadjib Benosmane. « Use of Polymer Inclusion Membrane for the Separation of Phenols Compounds Mixture from Dilute Aqueous Solutions ». Int. J. of Membrane Science and Technology 9, no 1 (18 août 2022) : 26–32. http://dx.doi.org/10.15379/2410-1869.2022.09.01.04.
Texte intégralRésumé :
Abstract: Separation of phenolic compounds mixture namely: phenol, resorcinol, Bisphenol A from dilute aqueous solutions by polymer inclusion membrane using Cellulose triacetate (CTA) as support was investigated as a means of recovering Bisphenol A from mixture of phenolic compounds. The effects of parameters influencing the separation performance were studied in terms of permeation flux and selectivity. For competitive transport of phenols across PIM with RC8 + NPOE, the selectivity order was Bisphenol > Phenol > Resorcinol. The high permselectivity of the membrane to Bisphenol A was primarily due to its high affinity towards calixresorcinarene macrocycle. This is of particular interest from an industrial point of view because the enriched phenol permeate can be easily recovered upon phase separation. The prepared PIM were characterized by using Raman spectroscopy, XPS and scanning electron microscopy (SEM) techniques.
Keywords: PIM, CTA, Membrane separation, Phenols mixture, Bisphenol A, Wastewater treatment.
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Zhang, Wanhui, Chaohai Wei, Chunhua Feng, Yuan Ren, Yun Hu, Bo Yan et Chaofei Wu. « The occurrence and fate of phenolic compounds in a coking wastewater treatment plant ». Water Science and Technology 68, no 2 (1 juillet 2013) : 433–40. http://dx.doi.org/10.2166/wst.2013.269.
Texte intégralRésumé :
The occurrence of 14 phenolic compounds (PCs) was assessed in the raw, treated wastewater, dewatered sludge and gas samples from a coking wastewater treatment plant (WWTP) in China. It was found that 3-cresol was the dominant compound in the raw coking wastewater with a concentration of 183 mg L−1, and that chlorophenols and nitrophenols were in the level of μg L−1. Phenol was the dominant compound in the gas samples, while 2,4,6-trichlorophenol predominated in the dewatered sludge sample. The anaerobic and aerobic tanks played key roles in the elimination of chlorophenols and phenols, respectively. Analysis of daily mass flows of PCs in WWTP showed that 89–98% of phenols and 83–89% of nitrophenols were biodegraded, and that 44–69% of chlorophenols were adsorbed to sludge, indicating that the fate of PCs was highly influenced by their biodegradability and physical–chemical property.
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El-Yazal, Mohamed A. Seif. « Metabolic Changes in Phenolic Compounds in Buds during and after Dormancy Releasing in early and late (Malus sylvestris, Mill) Apple Varieties as Effected by Chilling Requirements ». International Letters of Natural Sciences 81 (février 2021) : 13–22. http://dx.doi.org/10.18052/www.scipress.com/ilns.81.13.
Texte intégralRésumé :
In order to study the relation between seasonal changes in phenolic compounds and flower opining date according to chilling requirements. The early and late-opining apple varieties, Barkhar, Local and Strakhan (Malussylvestris) were used. This study investigated variations in chilling requirements, bud burst and development in early and late varieties of apple trees. Results showed less bud burst in late varieties than in early ones. In the former, there were increased in phenolic compounds (conjugated and total phenols) at budburst in all varieties. As dormancy begins, free phenols are increased, coinciding with a reduction in the levels of conjugated phenols. Consequently, as dormancy breaks, these free phenols are conjugate with organic constituents, and a decrease in the concentrations of free phenols occurs, in order to reduce inhibitory effect on growth. We conclude that late varieties (Strakhan) are less economical in manufacturing new growth, as indicated by less bud vigor at budburst than early varieties (Barkhar and local) and show a marked differential phenols compound pattern throughout bud development compared to early varieties.
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El-Yazal, Sawsan A. Saif. « Metabolic Changes in Phenolic Compounds in Buds during and after Dormancy Releasing in early and late (<i>Malus sylvestris, </i>Mill) Apple Varieties as Effected by Chilling Requirements ». International Letters of Natural Sciences 81 (25 février 2021) : 13–22. http://dx.doi.org/10.56431/p-jfmdgu.
Texte intégralRésumé :
In order to study the relation between seasonal changes in phenolic compounds and flower opining date according to chilling requirements. The early and late-opining apple varieties, Barkhar, Local and Strakhan (Malussylvestris) were used. This study investigated variations in chilling requirements, bud burst and development in early and late varieties of apple trees. Results showed less bud burst in late varieties than in early ones. In the former, there were increased in phenolic compounds (conjugated and total phenols) at budburst in all varieties. As dormancy begins, free phenols are increased, coinciding with a reduction in the levels of conjugated phenols. Consequently, as dormancy breaks, these free phenols are conjugate with organic constituents, and a decrease in the concentrations of free phenols occurs, in order to reduce inhibitory effect on growth. We conclude that late varieties (Strakhan) are less economical in manufacturing new growth, as indicated by less bud vigor at budburst than early varieties (Barkhar and local) and show a marked differential phenols compound pattern throughout bud development compared to early varieties.
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Olivas-Aguirre, Miguel, Liliana Torres-López, Igor Pottosin et Oxana Dobrovinskaya. « Phenolic Compounds Cannabidiol, Curcumin and Quercetin Cause Mitochondrial Dysfunction and Suppress Acute Lymphoblastic Leukemia Cells ». International Journal of Molecular Sciences 22, no 1 (28 décembre 2020) : 204. http://dx.doi.org/10.3390/ijms22010204.
Texte intégralRésumé :
Anticancer activity of different phenols is documented, but underlying mechanisms remain elusive. Recently, we have shown that cannabidiol kills the cells of acute lymphoblastic leukemia (ALL) by a direct interaction with mitochondria, with their consequent dysfunction. In the present study, cytotoxic effects of several phenolic compounds against human the T-ALL cell line Jurkat were tested by means of resazurin-based metabolic assay. To unravel underlying mechanisms, mitochondrial membrane potential (∆Ψm) and [Ca2+]m measurements were undertaken, and reactive oxygen species generation and cell death were evaluated by flow cytometry. Three out of eight tested phenolics, cannabidiol, curcumin and quercetin, which displayed a significant cytotoxic effect, also dissipated the ∆Ψm and induced a significant [Ca2+]m increase, whereas inefficient phenols did not. Dissipation of the ∆Ψm by cannabidiol was prevented by cyclosporine A and reverted by Ru360, inhibitors of the permeation transition pore and mitochondrial Ca2+ uniporter, respectively. Ru360 prevented the phenol-induced [Ca2+]m rise, but neither cyclosporine A nor Ru360 affected the curcumin- and quercetin-induced ∆Ψm depolarization. Ru360 impeded the curcumin- and cannabidiol-induced cell death. Thus, all three phenols exert their antileukemic activity via mitochondrial Ca2+ overload, whereas curcumin and quercetin suppress the metabolism of leukemic cells by direct mitochondrial uncoupling.
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Arvind, Mahesh. « Biodegradation of Phenolic Pollutants ». Mapana - Journal of Sciences 12, no 4 (16 juillet 2013) : 9–18. http://dx.doi.org/10.12723/mjs.27.2.
Texte intégralRésumé :
Phenolic compounds are important constituents of petrochemical waste waters arising from transformation processes. Phenol together with substituted halophenols, nitrophenols and alkyl phenols are the main constituents. An Arthrobacter citreus spp. strain MSA - 2005 initially selected for growth at the expense of phenol as the sole source of carbon and energy, was enriched with phenolic compounds such as 4-nitrophenol, 4- chlorophenol and 4-methyl phenol. Metabolization of these compounds upto their maximum levels in the mineral salt medium was studied. The complete metabolization of 4-nitrophenol upto 15mM, 4- chlorophenol up to 12mM and 4-methyl phenol upto 6mM against phenol upto 22mM was achieved in 24 hours. The metabolism of these compounds by the isolated strain occurred through the involvement of catechol derivatives as key intermediates which are further hydrolysed to hydroxy quinol which enters the β -keto adipate pathway. Results indicate that the cells contain mono and di- oxygenase enzymes necessary for these conversions. The degradation rates of these phenolic compounds, by agar immobilized cells has also been reported.
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Nagarajan, Subhalakshmi, Ramaswamy Nagarajan, Jayant Kumar, Adele Salemme, Anna Rita Togna, Luciano Saso et Ferdinando Bruno. « Antioxidant Activity of Synthetic Polymers of Phenolic Compounds ». Polymers 12, no 8 (24 juillet 2020) : 1646. http://dx.doi.org/10.3390/polym12081646.
Texte intégralRésumé :
In recent years, developing potent antioxidants has been a very active area of research. In this context, phenolic compounds have been evaluated for their antioxidant activity. However, the use of phenolic compounds has also been limited by poor antioxidant activity in several in vivo studies. Polymeric phenols have received much attention owing to their potent antioxidant properties and increased stability in aqueous systems. To be truly effective in biological applications, it is important that these polymers be synthesized using benign methods. In this context, enzyme catalyzed synthesis of polymeric phenols has been explored as an environmentally friendly and safer approach. This review summarizes work in enzymatic syntheses of polymers of phenols. Several assays have been developed to determine the antioxidant potency of these polymeric phenols. These assays are discussed in detail along with structure-property relationships. A deeper understanding of factors affecting antioxidant activity would provide an opportunity for the design of versatile, high performing polymers with enhanced antioxidant activity.
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Jennings, JG, R. de Nys, TS Charlton, MW Duncan et PD Steinberg. « Phenolic compounds in the nearshore waters of Sydney, Australia ». Marine and Freshwater Research 47, no 8 (1996) : 951. http://dx.doi.org/10.1071/mf9960951.
Texte intégralRésumé :
Ten pollutant phenols extracted from an oil refinery discharge, urban storm water and sewage effluent were analysed by gas chromatography-mass spectrometry. Recoveries varied from 43% to 97%, with a detection limit of 0.5 μg L-1. Concentrations ranged from below the detection limit up to 114.0μg L-1, the highest being in sewage effluent. The most common were phenol and cresol. The effects of similar concentrations were determined in bioaccumulation experiments using the mussel Mytilus edulis and fish Trachurus novaezelandiae. Recoveries of phenols from tissues were 10-40%, with a detection limit of 0.5 ng g-1. 2,4-dimethylphenol, 2,4-dichlorophenol, 4-chloro, 3-methylphenol, 2,4,6-trichlorophenol and pentachlorophenol were accumulated, with bioconcentration factors ranging from 2.51 � 0.51 for dimethylphenol to 283.8 � 5.58 for pentachlorophenol; when placed in clean sea water, both species depurated all accumulated phenols to concentrations below detection within 24 h. Neither phenol nor cresol were accumulated. Phenol and o-cresol inhibited the germination of Ulva lactuca gametes at concentrations above 1 mg L-1 (100 times the concentrations detected in the water samples). Muscle and liver tissue from fish and invertebrates collected from the oil refinery discharge site in Botany Bay and control localities contained no detectable phenols.
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Chen, Jian, Wim H. Rulkens et Harry Bruning. « Photochemical elimination of phenols and cod in industrial wastewaters ». Water Science and Technology 35, no 4 (1 février 1997) : 231–38. http://dx.doi.org/10.2166/wst.1997.0126.
Texte intégralRésumé :
It is demonstrated that toxic pollutants such as phenols in industrial wastewaters can be eliminated efficiently by photochemical methods using a combination of UV and heterogeneous photocatalyst, and combinations of UV, H2O2, and ferric compounds. The combination of UV and photocatalyst even decreases the COD of some of the toxic industrial wastewater around 60–70% in 1–4 hour treatment time depending on the source of the wastewater. The different combinations of UV (200 W high pressure mercury lamp, wavelength 313 ≤ λ ≤ 456 nm), magnetite or aluminium oxide (as photocatalyst), H2O2 and iron compounds (FeCl3, Fe(NH3)2(SO4)2, as Fenton reagent) were used in lab scale experiments to examine the elimination at aerated conditions of pure phenol in solutions (initial concentration = 25 ppm) and of substituted phenols and COD in industrial wastewaters originally from phenolic resin manufacture, oil refinement, shale oil dry distillation, and naphthenic acid production. The results clearly show the separate and combined effect of UV, Ferric compounds and H2O2 on the elimination of phenols and COD.
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Zhang, Huifen, Jing Pu, Yan Tang, Miao Wang, Kun Tian, Yongqing Wang, Xian Luo et Qunxian Deng. « Changes in Phenolic Compounds and Antioxidant Activity during Development of ‘Qiangcuili’ and ‘Cuihongli’ Fruit ». Foods 11, no 20 (13 octobre 2022) : 3198. http://dx.doi.org/10.3390/foods11203198.
Texte intégralRésumé :
Plums are widely consumed, contain high levels of phenolic compounds, and have strong antioxidant activity. In this study, the main Sichuan cultivars ‘Qiangcuili’ and ‘Cuihongli’ were used to study the changes in the appearance, internal quality, phenolic compounds, and antioxidant activities during fruit development and the expression of phenolic-compound-related structural genes. The results showed that, during development of the two plums, the total soluble solid and soluble sugar contents were highest at the mature stage. The phenolic contents (total phenol content (TPC), total flavonoid content (TFC), and total flavanol content (TFAC)) trended gradually downward as the fruits of the two cultivars matured, while the total anthocyanin content gradually increased in ‘Cuihongli’. The main phenolic components were neochlorogenic acid, chlorogenic acid, ferulic acid, benzoic acid, rutin, and proanthocyanidin B1. The changes in the DPPH and FRAP scavenging activities decreased with fruit ripening. The antioxidant capacity was positively correlated with the TPC, TFC, and TFAC. In the two cultivars, the total phenols, phenolic components, and antioxidant capacity were higher in the peel than in the pulp. CHS, PAL3, and HCT1 may be the regulatory genes related to the accumulation of phenolic substances in the pericarp and pulp of ‘Qiangcuili’ and ‘Cuihongli’. HCT1 may be an important regulator involved in the accumulation of chlorogenic acid in plums. The changes in the quality of the phenols, phenolic components, and antioxidant activity were elucidated during the development of the main plum cultivars in Sichuan, particularly the changes that provided a theoretical basis for the development of bioactive substances in local plum cultivars.
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Tarasevičienė, Živilė, Aloyzas Velička et Aurelija Paulauskienė. « Impact of Foliar Application of Amino Acids on Total Phenols, Phenolic Acids Content of Different Mints Varieties under the Field Condition ». Plants 10, no 3 (23 mars 2021) : 599. http://dx.doi.org/10.3390/plants10030599.
Texte intégralRésumé :
Phenolic compounds have a number of benefits to human health and can be used as preventive compounds for the development of some chronic diseases. Mentha plants are not only a good source of essential oils, but also contain significant levels of wide range of phenolic compounds. The aim of this research was to investigate the possibility to increase phenols content in Mentha plants under the foliar application with L-phenylalanine, L-tryptophan, L-tyrosine at two concentrations (100 mg L−1 and 200 mg L−1) and to create preconditions for using this plant for even more diverse purposes. Quantitative and qualitative analyses of phenols in mints were performed by HPLC method. Foliar application of amino acids increased the total phenol content from 1.22 to 3.51 times depending on the treatment and mint variety. The most pronounced foliar application to total phenols content was tryptophane especially in Mentha piperita “Swiss”. Mentha piperita “Swiss” was affected most by foliar application and the amount of total phenolic acids depending on the treatment ranged from 159.25 to 664.03 mg 100 g−1 (DW), respectively, non-sprayed and sprayed with tryptophane 100 mg L−1. Our results suggest that the biophenol content varies according to such factors as foliar application and variety, and every single mint variety has individual response to different applications of amino acids.
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Ananta, I. Gusti Bagus Teguh, et Dewa Gede Anom Anjasmara. « Antioxidant and Antibacterial Potency of Red Chillies Extract (Capsicum annum var. Longum) ». Jurnal Ilmiah Medicamento 8, no 1 (29 mars 2022) : 48–55. http://dx.doi.org/10.36733/medicamento.v8i1.3170.
Texte intégralRésumé :
Chili (Capsicum annum var. Longum) is a horticultural plant that is widely used as raw material for the food and pharmaceutical industry. Generally, chili fruit contains phenolic chemical compounds of flavonoid and capcaisinoid compounds. Bioactive compounds in chili such as phenols, flavonoids and capsaicinoid have a positive relationship to antioxidant and antimicrobial activity. Capsicum annum var. Longum contains secondary metabolites such as alkaloids, phenols, flavonoids, tannins and saponins. The total phenol content is 0.81% (807.76 mg GAE/100 g). The total content of flavonoids is 5.64% (5646.08 mg QE/100 g). Antioxidant activity was carried out using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method with an IC50 value of 505.35 ppm. Antibacterial activity was carried out by disc diffusion method with the growth inhibition of Escherichia coli bacteria of 8.56 mm and Staphylococcus aureus of 3.55 mm.
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Perez-Perez, Liliana Maribel, José Ángel Huerta-Ocampo, Saúl Ruiz-Cruz, Francisco Javier Cinco-Moroyoqui, Francisco Javier Wong-Corral, Luisa Alondra Rascón-Valenzuela, Miguel Angel Robles-García et al. « Evaluation of Quality, Antioxidant Capacity, and Digestibility of Chickpea (Cicer arietinum L. cv Blanoro) Stored under N2 and CO2 Atmospheres ». Molecules 26, no 9 (8 mai 2021) : 2773. http://dx.doi.org/10.3390/molecules26092773.
Texte intégralRésumé :
The aim of this work was to monitor the quality, antioxidant capacity and digestibility of chickpea exposed to different modified atmospheres. Chickpea quality (proximal analysis, color, texture, and water absorption) and the antioxidant capacity of free, conjugated, and bound phenol fractions obtained from raw and cooked chickpea, were determined. Cooked chickpea was exposed to N2 and CO2 atmospheres for 0, 25, and 50 days, and the antioxidant capacity was analyzed by DPPH (2,2′-diphenyl-1-picrylhydrazyl), ABTS (2,2′-azino-bis-[3ethylbenzothiazoline-6-sulfonic acid]), and total phenols. After in vitro digestion, the antioxidant capacity was measured by DPPH, ABTS, FRAP (ferric reducing antioxidant power), and AAPH (2,2′-Azobis [2-methylpropionamidine]). Additionally, quantification of total phenols, and UPLC-MS profile were determined. The results indicated that this grain contain high quality and high protein (18.38%). Bound phenolic compounds showed the highest amount (105.6 mg GAE/100 g) and the highest antioxidant capacity in all techniques. Cooked chickpeas maintained their quality and antioxidant capacity during 50 days of storage at 4 and −20 °C under a nitrogen atmosphere. Free and conjugated phenolic compounds could be hydrolyzed by digestive enzymes, increasing their bioaccessibility and their antioxidant capacity during each step of digestion. The majority compound in all samples was enterodiol, prevailing the flavonoid type in the rest of the identified compounds. Chickpea contains biological interest compounds with antioxidant potential suggesting that this legume can be exploited for various technologies.
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Kumar, R., Y. Raizner, L. I. Kruh, O. Menashe, H. Azaizeh, S. Kapur et E. Kurzbaum. « Extracellular laccase production and phenolic degradation by an olive mill wastewater isolate ». Grasas y Aceites 69, no 1 (22 mars 2018) : 231. http://dx.doi.org/10.3989/gya.0776171.
Texte intégralRésumé :
Olive mill wastewater (OMWW) presents a challenge to the control of effluents due to the presence of a high organic load, antimicrobial agents (monomeric-polymeric phenols, volatile acids, polyalcohols, and tannins), salinity and acidity. In this study, the production of extracellular laccase, monomeric or polymeric phenol, from an OMWW isolate based on its ability to biodegrade phenols and gallic acid as a model of phenolic compounds in OMWW was investigated. Phylogenetic analysis of the 16S RNA gene sequences identified the bacterial isolate (Acinetobacter REY) as being closest to Acinetobacter pittii. This isolate exhibited a constitutive production of extracellular laccase with an activity of 1.5 and 1.3 U ml/L when supplemented with the inducers CuSO4 and CuSO4+phenols, respectively. Batch experiments containing minimal media supplemented with phenols or gallic acid as the sole carbon and energy source were performed in order to characterize their phenolic biodegradability. Acinetobacter REY was capable of biodegrading up to 200 mg/L of phenols and gallic acid both after 10 h and 72 h, respectively.
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Bargebid, Rahele, Ali Khalafi-Nezhad, Kamiar Zomorodian, Mahkameh Moradi et Soghra Khabnadideh. « Silica gel Supported Boric tri-Sulfuric Anhydride (SiO2-BTSA) : An Efficient Catalytic System for the Synthesis of Phloroglucide Analogs as Antimicrobial Agents ». Anti-Infective Agents 18, no 4 (4 janvier 2021) : 419–28. http://dx.doi.org/10.2174/2211352517666190902142915.
Texte intégralRésumé :
Background: Polyhydroxy aromatic compounds are one of the most important classes of phenolic compounds with different biological activities. Some important and biologically active phenol-based compounds have also been isolated from nature. Methods: An efficient procedure for the synthesis of polyhydroxy aromatic compounds (phloroglucide analogs) is described. In this procedure, a reaction took place between different 4-substituted phenols and 2,6-bis(hydroxymethyl) phenols. The reactions proceed in the presence of catalytic amount of silica gel supported boric tri-sulfuric anhydride (SiO2-BTSA) in excellent yields. Results: 16 compounds were synthesized (I1-I16). Chemical structures of all the compounds were confirmed by spectroscopic methods. We optimized the chemical reactions in the presence of different acidic catalysts, different solvents and also different temperatures. A catalytic amount of SiO2-BTSA in dichloroethane (DCE) was the best condition. Some of the synthesized compounds were screened for their antimicrobial activities. Antifungal and antibacterial activities of the synthesized compounds were evaluated by broth microdilution method as recommended by CLSI. Some of the tested compounds showed good in vitro biological properties. Conclusion: Our active compounds could introduce as good candidates for further studies as antimicrobial agents.
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Arvin, Erik, Bjørn K. Jensen et Anders Torp Gundersen. « Biodegradation Kinetics of Phenols in an Aerobic Biofilm at Low Concentrations ». Water Science and Technology 23, no 7-9 (1 avril 1991) : 1375–84. http://dx.doi.org/10.2166/wst.1991.0590.
Texte intégralRésumé :
Aerobic biodegradation of the phenols: phenol, 2-methylphenol, 4-methylphenol, 2,4-dimethylphenol, 3,5-dimethylphenol and 2,4,6-trimethylphenol was studied in a biofilm reactor to establish kinetic constants under conditions where the phenols were the sole carbon sources. Phenol concentrations were very low, in the µg/l concentration range. 2,4,6-trimethylphenol was not degraded. The degradation of the other phenols was 1'st order at concentrations in the bulk phase below 20-50 µg/l. Zero order reaction seemed to govern the reaction above 200 µg/l. The l'st order rate constants are 3-30 times higher than the constants calculated for easily degradable organic compounds degraded at 100-1000 times higher concentrations (mg/l range). However, the maximum phenol utilization rates and the Monod constants were much lower compared with constants obtained for the microorganisms grown in the mg/l concentration range. The Monod constant was about 100 times lower. The removal of “total biodegradable phenol” (TB-phenol) was very similar to the removal of a specific compound. The degradation of TB-phenol was l'st order at concentrations below 200 µg/l. When the total biodegradable phenol degradation is near its maximum capacity (o'order reaction) there was a preferential degradation of the most easily degradable phenols, phenol and 2-methylphenol, leading to an apparent inhibition of the degradation of the more slowly degradable phenols, in particular 2,4-dimethylphenol and 3,5-dimethylphenol.
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Zhu, Yi-Lin, Hai-Sheng Zhang, Xin-Shuai Zhao, Huan-Huan Xue, Jing Xue et Yu-Han Sun. « Composition, Distribution, and Antioxidant Activity of Phenolic Compounds in 18 Soybean Cultivars ». Journal of AOAC INTERNATIONAL 101, no 2 (1 mars 2018) : 520–28. http://dx.doi.org/10.5740/jaoacint.17-0156.
Texte intégralRésumé :
Abstract Natural phenols are an important functional compound widely distributed in plants with benefits that promote human health. The content of total phenols, flavonoids, and anthocyanins and their composition distribution in 18 soybean cultivars was investigated. There are four phenolic acid distribution forms in these soybean cultivars, namely free, esterified, glycosided, and insoluble-bound. Total phenols, flavonoids, and anthocyanins from 6 black soybean cultivars were found in higher numbers than those from 12 other yellow soybean cultivars. Free and esterified phenolic acids were the main phenolic acid form in all 18 soybean samples. Chlorogenic acid and caffeic acid were the dominant phenolic acids in eight detected phenolic acids, and daidzin and genistin were the abundant isoflavones in five detected isoflavones. Furthermore, the antioxidant activities of total phenols from the 6 black soybean cultivars were greater than those from the 12 yellow soybean cultivars, and there was a significant positive correlation between antioxidant activity and total phenolic content. Black soybeans could be a potential resource for developing natural antioxidants that may play a crucial role in human health protection.
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Xiao, Zi Jun, Rui Qian Qi, Fang Fang Huo, Yun Ling Huang, Hai Xu et Jian R. Lu. « Microbial Screening Strategies for Biodegradation of Monocyclic Phenolic Compounds ». Advanced Materials Research 354-355 (octobre 2011) : 1386–89. http://dx.doi.org/10.4028/www.scientific.net/amr.354-355.1386.
Texte intégralRésumé :
Wastewaters discharged from oil refineries and coal coking plants often contain large amounts of toxic monocyclic phenolic compounds (MCPCs), mainly including phenol, cresols and xylenols, polluting soils and surface water. In this work, crude phenols or 12 individual MCPCswere used as the enrichment medium and the later strategy was discovered for the first time to be more effective in finding more and competent MCPC-degrading strains. Phylogenetic analysis and multiple MCPC degradation tests revealed that phylogenetically close microbes generally exhibited similar MCPC-degrading spectra.
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Revutska, A. Z., V. N. Belava, A. V. Golubenko et N. Yu Taran. « Content of phenolic compounds in Acorus calamus L. tissue culture and nutrient culture medium under in vitro conditions ». Visnik ukrains'kogo tovaristva genetikiv i selekcioneriv 14, no 2 (31 décembre 2016) : 203–9. http://dx.doi.org/10.7124/visnyk.utgis.14.2.690.
Texte intégralRésumé :
Aim. To find out the biochemical peculiarities of Acorus calamus L of the two genotypes, acquired from different populations, an analysis of phenolic compounds in explant tissues and in nutrient medium in vitro was conducted. Methods. Plants, acquired by microclonal multiplication were studied. To detect general phenol content, Folin–Ciocalteu reagent was used, for flavonoid content - zirconium chloride crystallohydrate nitrate (IV). Xanthone content was identified by Vysochina G.I. and Kukushkina T.A. methods with our own modifications. The extracts were studied using spectrophotometric measurements. Results. Tissues of A. calamus and the nutrient medium contained different amount of phenolic compounds, depending on parent plant origin and in vitro cultivation duration. Conclusions. Since the explants were cultivated in identical conditions, the difference of phenolic compound content both in tissues and nutrient medium indicates genetic variability of A. calamus plants on population level. Key words. Acorus calamus, culture in vitro, phenols, flavonoids, xanthones.
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Abraham Sisein Eboh, Faith Owabhel Robert et Wodu Ebizimor. « Phenolics and phytochemicals in methanolic extract of Peperomia pellucidia quantified by HPLC ». Open Access Research Journal of Life Sciences 3, no 2 (30 juin 2022) : 059–62. http://dx.doi.org/10.53022/oarjls.2022.3.2.0045.
Texte intégralRésumé :
Phenolics are compounds that contributed greatly to the healing potentials of many herbs, spices and plants of which Peperomia pellucidia is inclusive. This research aimed at determining the various phenolics present in the methanolic extract of Peperomia pellucidia extract. High performance liquid chromatography was used to analyse the phenolic content in Peperomia pellucidia extract. The result showed the presence of phenols and flavonoid quantified as total phenol 12.78 ± 2.70 mg GAE/g dry extract and total flavonoid as 10.97 ± 0.00 mg QE/g dry extract. HPLC result reveals the following phenols p-coumaric acid 32.76 mg/100g, gallic acid with a concentration of 138.07 mg/100 g. caffeic acid and naringenin were also detected in larger concentration as showed in the table. Ferulic acid, syringic acid and quercetin each has a retention time of 17.09, 17.47 and 22.60 min, a percentage area of 136.77, 96.93 and 91.06 while the concentrations where 16.129 mg/100g, 17.688 and 75.56 mg/100g respectively. Other phenolics with much higher quantity are rosmarinic acid and chlorogenic acid with retention time 23.97 and 25.06, a percentage area of 94.44 and 24.48, while the amounts quantified in Peperomia pellucidia extract was 19.133 mg/100g and 28.865 mg/100g. In conclusion methanolic extract of Peperomia pellucidia showed a lot of phenols that are very useful in the alleviation of stress that is linked with many diseases.
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Ionescu, Mihail, et Zoran Petrovic. « Phenolation of vegetable oils ». Journal of the Serbian Chemical Society 76, no 4 (2011) : 591–606. http://dx.doi.org/10.2298/jsc100820050i.
Texte intégralRésumé :
Novel bio-based compounds containing phenols suitable for the synthesis of polyurethanes were prepared. The direct alkylation of phenols with different vegetable oils in the presence of superacids (HBF4, triflic acid) as catalysts was studied. The reaction kinetics was followed by monitoring the decrease of the double bond content (iodine value) with time. In order to understand the mechanism of the reaction, phenol was alkylated with model compounds. The model compounds containing one internal double bond were 9-octadecene and methyl oleate and those with three double bonds were triolein and high oleic safflower oil (82% oleic acid). It was shown that the best structures for phenol alkylation are fatty acids with only one double bond (oleic acid). Fatty acids with two double bonds (linoleic acid) and three double bonds (linolenic acid) lead to polymerized oils by a Diels Alder reaction, and to a lesser extent to phenol alkylated products. The reaction product of direct alkylation of phenol with vegetable oils is a complex mixture of phenol alkylated with polymerized oil (30-60%), phenyl esters formed by transesterification of phenol with triglyceride ester bonds (<10 %) and unreacted oil (30%). The phenolated vegetable oils are new aromatic-aliphatic bio-based raw materials suitable for the preparation of polyols (by propoxylation, ethoxylation, Mannich reactions) for the preparation of polyurethanes, as intermediates for phenolic resins or as bio-based antioxidants.
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Tantasut, J., H. Satoh, P. Parkpian et S. Mongkolsuk. « Effects of exposure times on the toxic response of ammonia oxidizing mixed culture (AOMC) to phenol and chlorinated phenols ». Water Science and Technology 54, no 11-12 (1 décembre 2006) : 281–88. http://dx.doi.org/10.2166/wst.2006.734.
Texte intégralRésumé :
This study investigated the effect of exposure times on the response of ammonia oxidizing mixed culture (AOMC) to phenolic compounds while having the future goal to develop a biosensor using AOMC for toxicity monitoring. AOMC was used instead of purified nitrifying culture because of the ease of culture development. The oxygen utilization rate (OUR) was measured during three exposure periods; 0–15, 25–40 and 50–65 min. It was found that phenolic compounds have a strong inhibitory effect on AOMC. The percentage of OUR reduction increased with higher concentrations and the extended exposure times improved the toxic response of AOMC, especially to the lower concentrations (0.25, 0.50, 1.0 mg/L). Further, AOMC detoxifying mechanisms might result in the reduction of toxic response when the longest exposure time was applied. However, at the higher concentrations (2.5 and 5.0 mg/L), the extended exposure times did not have a critical effect on the response pattern of AOMC, especially for phenol and mono-chlorinated phenols. It was illustrated that AOMC is very sensitive to phenolic compounds and its sensitivity is high enough for the detection of phenolic compounds at the level of effluent standard in Thailand and Japan with a rapid response time of 15 min. To improve the sensitivity of AOMC to low phenolic compound concentrations, an extended exposure time of 25–40 min would be recommended.
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da Silva, Allan Ribeiro, Tereza Cristina Monteiro Pastore, Jez Willian Batista Braga, Fabrice Davrieux, Esmeralda Yoshico Arakaki Okino, Vera Teresinha Rauber Coradin, José Arlete Alves Camargos et Alexandre Gustavo Soares do Prado. « Assessment of total phenols and extractives of mahogany wood by near infrared spectroscopy (NIRS) ». Holzforschung 67, no 1 (1 janvier 2013) : 1–8. http://dx.doi.org/10.1515/hf-2011-0207.
Texte intégralRésumé :
Abstract The resistance to decomposition of mahogany wood (Sweitenia macrophylla King) ranges from high to moderate level. Wood extractives, mainly due to the presence of phenol compounds are related to the natural durability of wood. The technique of near infrared spectroscopy (NIRS) coupled with multivariate analysis has been applied to assess the extractives and phenols of 41 samples of mahogany in powder form. The hot water-soluble extractives were quantitatively determined, and total phenol content was measured with the Folin-Denis colourimetric reagent. Models were developed with the NIRS data for each of the two variables. The results indicated that NIRS can be a useful tool to a rapid evaluation of the extractive contents and total phenolic compounds of mahogany wood. The method was able to predict the interesting properties with errors lower than 10% (w/w) and had the capability of detecting samples that have a minimum concentration of 2.4% (w/w) of extractives and total phenolic compounds, respectively.
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Arámbula-Salazar, Jorge Armando, Norma Almaraz-Abarca, José Javier Corral-Rivas, Eli Amanda Delgado-Alvarado, Raúl Díaz-Moreno et Eusebio Montiel-Antuna. « Variability in Foliar Phenolic Composition of Several Quercus Species in Northern Mexico ». Pakistan Journal of Scientific & ; Industrial Research Series A : Physical Sciences 58, no 2 (24 juin 2015) : 79–89. http://dx.doi.org/10.52763/pjsir.phys.sci.58.2.2015.79.89.
Texte intégralRésumé :
Quantitative and qualitative composition of the foliar phenolic compounds were investigated in 81 individual specimens of several white oak species (Quercus spp.). The trees were growing in twelve locations in Durango, Mexico. The phenol profiles were determined by HPLC-DAD and a Folin-Ciocateu procedure. The results revealed that: (i) the foliar phenol profiles of all species analysed were complex and formed by 6 to 30 compounds, (ii) the flavonols mostly quercetin glycoside, isorhamnetin glycoside, kaempferol glycoside and phenolic acids were the main identified compounds, (iii) there was a high intra and inter-specific variability in the foliar phenol profiles both at the quantitative and qualitative levels, and (iv) the foliar phenol profiles indicated a slight species-specific tendency for phenols to be accumulated, although this was not clearly distinguished. Significant differences (P < 0.05) in the content and composition of the foliar flavonoids between species were observed due to the large environmental and soil conditions variability between localities.
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Suárez, Manuel, Rosa M. Valls, Maria-Paz Romero, Alba Macià, Sara Fernández, Montse Giralt, Rosa Solà et Maria-José Motilva. « Bioavailability of phenols from a phenol-enriched olive oil ». British Journal of Nutrition 106, no 11 (21 juin 2011) : 1691–701. http://dx.doi.org/10.1017/s0007114511002200.
Texte intégralRésumé :
Phenolic compounds are one of the main reasons behind the healthy properties of virgin olive oil (VOO). However, their daily intake from VOO is low compared with that obtained from other phenolic sources. Therefore, the intake of VOO enriched with its own phenolic compounds could be of interest to increase the daily dose of these beneficial compounds. To evaluate the effectiveness of enrichment on their bioavailability, the concentration of phenolic compounds and their metabolites in human plasma (0, 60, 120, 240 and 300 min) from thirteen healthy volunteers (seven men and six women, aged 25 and 69 years) was determined after the ingestion of a single dose (30 ml) of either enriched virgin olive oil (EVOO) (961·17 mg/kg oil) or control VOO (288·89 mg/kg oil) in a cross-over study. Compared with VOO, EVOO increased plasma concentration of the phenol metabolites, particularly hydroxytyrosol sulphate and vanillin sulphate (P < 0·05). After the consumption of VOO, the maximum concentration of these peaks was reached at 60 min, while EVOO shifted this maximum to 120 min. Despite these differences, the wide variability of results indicates that the absorption and metabolism of olive oil phenols are highly dependent on the individual.
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Davidescu, Corneliu-Mircea, Radu Ardelean et Adriana Popa. « New polymeric adsorbent materials used for removal of phenolic derivatives from wastewaters ». Pure and Applied Chemistry 91, no 3 (26 mars 2019) : 443–58. http://dx.doi.org/10.1515/pac-2018-1019.
Texte intégralRésumé :
Abstract Phenolic compounds are produced in thermal cracking processes, drugs and herbicides synthesis and other industrial processes. Such compounds exhibit high toxicity for aquatic environment and for aquatic life. So, due to their high toxicity is important to treat waters with phenols content. For the treatment of waste waters containing phenols or phenolic compounds several unconventional methods are applied, such as: inverse osmosis, coagulation, solvent extraction, flotation–coagulation combined processes, adsorption, and anaerobic processes. From all used remediation processes adsorption has a higher applicability degree due to its main advantages: simplicity, ease of use and operation and high efficiency. Through time activated carbon and ashes were used as adsorbent materials for phenols remediation, but such materials present the main disadvantage of low regeneration degree. Thus, it is important to develop and use new adsorbents with higher regeneration degree and longer life time. Polymeric materials have been used for removal of organic compounds and/or metal ions from contaminated water due to their versatility in functionality, morphology and texture properties. Chemical modification of polymeric matrices with pendant functional groups is a valuable method used to improve the surface and interface chemistry of polymeric adsorbents, to achieve better adsorption performance and to design tailor-made adsorbents with respect to specific pollutants. In present study new adsorbent materials were obtained starting from chloromethylated styrene-divinylbenzene copolymers with different degrees of crosslinking (6.7%, 12% and respectively 15% DVB), functionalized by reaction with 3-hydroxibenzaldehyde. The polymeric intermediates were further modified by polymer-analogous reaction with iso-propylamine and diethylphosphite with the aim to improve their adsorptive properties. The obtained polymeric adsorbents were tested for remediation of waters containing phenol (P), 2,3-dimethylphenol (2,3-DMP) and 2,4,6-trimethyl-phenol (2,4,6-TMP). Based on obtained experimental data the adsorption mechanism, process kinetics and thermodynamics were studied.
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Buitrón, Germán, et Ariel González. « Characterization of the microorganisms from an acclimated activated sludge degrading phenolic compounds ». Water Science and Technology 34, no 5-6 (1 septembre 1996) : 289–94. http://dx.doi.org/10.2166/wst.1996.0562.
Texte intégralRésumé :
The microorganisms responsible for the degradation of a mixture of phenol, 4-chlorophenol (4CP), 2,4-dichlorophenol (24DCP) and 2,4,6-trichlorophenol (246TCP) were isolated and characterized in terms of its degradation rate. Activated sludge was acclimated for 70 days to 40 mg phenols/l. After this period the microorganisms responsible for the chlorinated phenol degradation were isolated and identified. Four types of Gram negative bacteria (Aeromonas sp., Pseudomonas sp. Flavimonas oryzihabitans, and Chryseomonas luteola) and Mycobacterium sp. were identified. The degradation kinetics of each phenol by Aeromonas sp.,Pseudomonas sp. Flavimonas oryzihabitans, Chryseomonas luteola and activated sludge were determined. The degradation of phenolic compounds was sequential: phenol and 4CP were first degraded, following by 24DCP and then by 246TCP. The acclimated activated sludge was from one to two orders of magnitude faster than the pure strains, when uptake rates were calculated in terms of the viable biomass (CFU). The qx for acclimated activated sludge varied between 8.2 and 15.8 × 10−7 mg/CFU-d (407–784 mg/gVSS-d). Aeromonas sp. presented the highest qx of the pure strains, based on a VSS basis (33–57 mg/gVSS-d) but, in terms of viable biomass (5.0–15.6 × 10−8 mg/CFU-d) Pseudomonas sp. did. Specific substrate uptake rate was 1.8 mg chlorinated phenols/g VSS-d for non-acclimated activated sludge.
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Genovese, Alessandro, Ferdinando Mondola, Antonello Paduano et Raffaele Sacchi. « Biophenolic Compounds Influence the In-Mouth Perceived Intensity of Virgin Olive Oil Flavours and Off-Flavours ». Molecules 25, no 8 (23 avril 2020) : 1969. http://dx.doi.org/10.3390/molecules25081969.
Texte intégralRésumé :
In this study, the influence of phenolic compounds on the sensory scores attributed to extra virgin olive oil (EVOO) by panel test was investigated. Two model olive oils (MOOs) with identical concentrations of volatile compounds, differing only in the amount of biophenols (297 vs. 511 mg kg−1), were analysed by two official panels and by SPME-GC/MS. Six other MOOs set up by the two previous models were also tested and analysed. They were formulated separately with the addition of three off-flavours (‘rancid’, ‘winey–vinegary’ and ‘fusty–muddy’). While high levels of EVOO phenolic compounds did not produce any effect on the headspace concentration of volatile compounds, they did affect the scores of both positive and negative sensory attributes of EVOO, due to the well-known in-mouth interactions between EVOO phenols, saliva and volatile compounds. In particular, a decrease of about 39% in the positive fruity score was found in the presence of a higher concentration of phenols. Regarding EVOO off-flavours, the higher level of phenolic compounds decreased by about 23% the score of ‘fusty–muddy’ defect and increased the score of ‘winey–vinegary’ defect about 733%. No important effect of EVOO phenolics on the perceived intensity of the ‘rancid’ defect was found. These findings could be helpful in explaining some discrepancies of panel test responses observed during extra virgin olive oil shelf life.
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Thangaraj, T., A. Vinayakam et K. Nellaiappan. « Phenol oxidase activity of a monogenean, Paramazocraes thrissocles ». Journal of Helminthology 60, no 3 (septembre 1986) : 234–38. http://dx.doi.org/10.1017/s0022149x00026158.
Texte intégralRésumé :
AbstractThe phenol oxidase of a monogenean, Paramazocraes thrissocles, oxidizes phenolic amines more effectively than other phenols studied. Based on the substrate specificity, the probable substrate for eggshell formation has been suggested. The enzyme shows the pH optimum of 7–2. At 40°C it shows maximum activity. Proenzyme is activated by metal ions and detergents. Copper chelating compounds strongly inhibit the enzyme.
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Liang, Hongmin, Deyan Gao, Cong Wang, Huanhuan Gao, Yayun Guo, Zhiyun Zhao et Hongmei Shi. « Effect of Fermentation Strategy on the Quality and Aroma Characteristics of Yellow Peach Wines ». Fermentation 8, no 11 (4 novembre 2022) : 604. http://dx.doi.org/10.3390/fermentation8110604.
Texte intégralRésumé :
To obtain high-quality yellow peach wines of varying characteristics, different fermentation strategies, including various pre-fermentative treatments, were applied. This study aimed to determine the effect of different fermentation strategies on the physicochemical properties, monomer phenol content, in vitro antioxidant activity, and volatile compounds of yellow peach wine. The results showed that peach wine P12, fermented with pulp, had higher total phenolic content (TPC), total flavonoid content (TFC), monomer phenol and volatile compound content, and antioxidant activity. Ten monomeric phenols were detected in peach wines, and the content of catechin was the highest. Juice fermentation wine, J12, had a strong floral aroma, and some volatile compounds were released during fermentation when water was added to the pulp, and low alcohol content did not reduce the variety of volatile compounds. The main aroma and common characteristics of the fermented yellow peach wine were dominated by esters, with a relative odor activity value (ROAV) ≥ 1, namely, isoamyl acetate, ethyl hexanoate, and ethyl octanoate. Our results demonstrated that the application of the described fermentation strategies significantly affected the quality and volatile compound content of yellow peach wines. This might assist in the development of a highly diverse yellow peach wine flavor.
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Narduzzi, Luca, Vicente Agulló, Claudia Favari, Nicole Tosi, Cristiana Mignogna, Alan Crozier, Daniele Del Rio et Pedro Mena. « (Poly)phenolic compounds and gut microbiome : new opportunities for personalized nutrition ». Microbiome Research Reports 1, no 2 (2022) : 16. http://dx.doi.org/10.20517/mrr.2022.06.
Texte intégralRésumé :
For decades, (poly)phenols have been linked to cardiometabolic health, but population heterogeneity limits their apparent efficacy and the development of tailored, practical protocols in dietary interventions. This heterogeneity is likely determined by the existence of different metabotypes, sub-populations of individuals metabolizing some classes of (poly)phenols differently. The gut microbiota plays a major role in this process. The impact of microbiota-related phenolic metabotypes on cardiometabolic health is becoming evident, although the picture is still incomplete, and data are absent for some classes of (poly)phenols. The lack of a complete understanding of the main microbial actors involved in the process complicates the picture. Elucidation of the mechanisms behind phenolic metabotypes requires novel experimental designs that can dissect the inter-individual variability. This paper, in addition to providing an overview on the current state-of-the-art, proposes wider metabotyping approaches as a means of paving the way towards effective personalized nutrition with dietary (poly)phenols.
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Ammar, Achraf, Khaled Trabelsi, Omar Boukhris, Bassem Bouaziz, Patrick Müller, Jordan M. Glenn, Karim Chamari et al. « Moderators of the Impact of (Poly)Phenols Interventions on Psychomotor Functions and BDNF : Insights from Subgroup Analysis and Meta-Regression ». Nutrients 12, no 9 (19 septembre 2020) : 2872. http://dx.doi.org/10.3390/nu12092872.
Texte intégralRésumé :
Background: Recent anti-aging interventions have shown contradictory impacts of (poly)phenols regarding the prevention of cognitive decline and maintenance of brain function. These discrepancies have been linked to between-study differences in supplementation protocols. This subgroup analysis and meta-regression aimed to (i) examine differential effects of moderator variables related to participant characteristics and supplementation protocols and (ii) identify practical recommendations to design effective (poly)phenol supplementation protocols for future anti-aging interventions. Methods: Multiple electronic databases (Web of Science; PubMed) searched for relevant intervention published from inception to July 2019. Using the PICOS criteria, a total of 4303 records were screened. Only high-quality studies (n = 15) were included in the final analyses. Random-effects meta-analysis was used, and we calculated standard differences in means (SDM), effect size (ES), and 95% confidence intervals (CI) for two sufficiently comparable items (i.e., psychomotor function and brain-derived neurotrophic factor (BDNF)). When significant heterogeneity was computed (I2 > 50%), a subgroup and meta-regression analysis were performed to examine the moderation effects of participant characteristics and supplementation protocols. Results: The reviewed studies support the beneficial effect of (poly)phenols-rich supplementation on psychomotor functions (ES = −0.677, p = 0.001) and brain plasticity (ES = 1.168, p = 0.028). Subgroup analysis revealed higher beneficial impacts of (poly)phenols (i) in younger populations compared to older (SDM = −0.89 vs. −0.47 for psychomotor performance, and 2.41 vs. 0.07 for BDNF, respectively), (ii) following an acute compared to chronic supplementation (SDM = −1.02 vs. −0.43 for psychomotor performance), and (iii) using a phenolic compound with medium compared to low bioavailability rates (SDM = −0.76 vs. −0.68 for psychomotor performance and 3.57 vs. 0.07 for DBNF, respectively). Meta-regressions revealed greater improvement in BDNF levels with lower percentages of female participants (Q = 40.15, df = 6, p < 0.001) and a skewed scatter plot toward a greater impact using higher (poly)phenols doses. Conclusion: This review suggests that age group, gender, the used phenolic compounds, their human bioavailability rate, and the supplementation dose as the primary moderator variables relating to the beneficial effects of (poly)phenol consumption on cognitive and brain function in humans. Therefore, it seems more advantageous to start anti-aging (poly)phenol interventions in adults earlier in life using medium (≈500 mg) to high doses (≈1000 mg) of phenolic compounds, with at least medium bioavailability rate (≥9%).