Journal articles: 'Polyphenolic oligomers'

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Alattiya, Reem Halim, Farah Khalid Tarish, Lina Loai Hashim, and Saad Abdulrahman Hussain. "The Role of Polyphenols in the Treatment of Alzheimer's Disease: Narrative Review." Al-Rafidain Journal of Medical Sciences ( ISSN: 2789-3219 ) 1 (October 13, 2021): 53–61. http://dx.doi.org/10.54133/ajms.v1i.31.

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Many epidemiological studies have suggested that consuming a diet rich in polyphenols can help prevent Alzheimer's disease (AD). Based on well-known in vitro and in vivo models of cerebral Aβ amyloidosis, we examined the data on the effects of various natural polyphenols on the aggregation of amyloid-protein (Aβ). These polyphenols effectively prevent oligomerization and fibril formation of Aβ through differential binding patterns, lowering Aβ oligomer-induced synaptic and neuronal toxicity, according to in vitro investigations. Furthermore, in a transgenic mouse model fed orally with such polyphenolic compounds, soluble Aβ oligomers as well as insoluble Aβ deposits in the brain were significantly reduced. Natural polyphenols exhibit anti-amyloidogenic effects on Aβ, in addition to well-known anti-oxidative and anti-inflammatory activities, according to an updated assessment of the literature, implying their potential as therapeutic and/or preventive agents for AD treatment. To prove polyphenols' efficacy as disease-modifying agents, well-designed clinical trials or preventive treatments using various polyphenols are required.

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Saéz, Riquelme, Baer, and Vallverdú-Queralt. "Phenolic Profile of Grape Canes: Novel Compounds Identified by LC-ESI-LTQ-Orbitrap-MS." Molecules 24, no. 20 (October 18, 2019): 3763. http://dx.doi.org/10.3390/molecules24203763.

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Grape canes (Vitis vinifera L.) are a viticulture industry by-product with an important content of secondary metabolites, mainly polyphenols with a broad spectrum of demonstrated health benefits. Grape canes, therefore, have considerable economic potential as a source of high-value phytochemicals. In this work, liquid chromatography coupled with electrospray ionization hybrid linear trap quadrupole-Orbitrap mass spectrometry (LC–LTQ-Orbitrap) was used for the comprehensive identification of polyphenolic compounds in grape canes. Identification of polyphenols was performed by comparing their retention times, accurate mass measured, and mass fragmentation patterns with those of reference substances or available data in the literature. A total of 75 compounds were identified, including phenolic acids, flavanols, flavonols, flavanonols, flavanones, and stilbenoids. The most abundant polyphenols were proanthocyanidins and stilbenoids and their oligomers. Moreover, the high-resolution mass spectrometry analysis revealed the occurrence of 17 polyphenols never described before in grape canes, thereby providing a more complete polyphenolic profile of this potentially valuable by-product.

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Ono, Kenjiro, Mayumi Tsuji, Tritia R. Yamasaki, and Giulio M. Pasinetti. "Anti-aggregation Effects of Phenolic Compounds on α-synuclein." Molecules 25, no. 10 (May 24, 2020): 2444. http://dx.doi.org/10.3390/molecules25102444.

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The aggregation and deposition of α-synuclein (αS) are major pathologic features of Parkinson’s disease, dementia with Lewy bodies, and other α-synucleinopathies. The propagation of αS pathology in the brain plays a key role in the onset and progression of clinical phenotypes. Thus, there is increasing interest in developing strategies that attenuate αS aggregation and propagation. Based on cumulative evidence that αS oligomers are neurotoxic and critical species in the pathogenesis of α-synucleinopathies, we and other groups reported that phenolic compounds inhibit αS aggregation including oligomerization, thereby ameliorating αS oligomer-induced cellular and synaptic toxicities. Heterogeneity in gut microbiota may influence the efficacy of dietary polyphenol metabolism. Our recent studies on the brain-penetrating polyphenolic acids 3-hydroxybenzoic acid (3-HBA), 3,4-dihydroxybenzoic acid (3,4-diHBA), and 3-hydroxyphenylacetic acid (3-HPPA), which are derived from gut microbiota-based metabolism of dietary polyphenols, demonstrated an in vitro ability to inhibit αS oligomerization and mediate aggregated αS-induced neurotoxicity. Additionally, 3-HPPA, 3,4-diHBA, 3-HBA, and 4-hydroxybenzoic acid significantly attenuated intracellular αS seeding aggregation in a cell-based system. This review focuses on recent research developments regarding neuroprotective properties, especially anti-αS aggregation effects, of phenolic compounds and their metabolites by the gut microbiome, including our findings in the pathogenesis of α-synucleinopathies.

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Denis, Marie-Claude, Pascal Dubé, Stéphanie Dudonné, Yves Desjardins, Cristina Matei, Edgard Delvin, Emile Levy, and Alexandra Furtos. "Characterization of bioactive cranberry fractions by mass spectrometry." Canadian Journal of Chemistry 98, no. 9 (September 2020): 589–96. http://dx.doi.org/10.1139/cjc-2020-0070.

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Increasing evidence indicates that fruits contain functional bio-active compounds that have several preventive and therapeutic health benefits. Our group has recently conducted studies to assess the potential effects of cranberry polyphenolic fractions on intestinal Caco-2/15 epithelial cells and a substantial reduction in oxidative stress and inflammation was observed. The aim of the present work was to determine the polyphenolic species most likely responsible for the observed biological activity. Low, medium, and high molecular weight cranberry fractions were generated with a Sephadex LH-20 column by elution with 60% MeOH, 100% MeOH, and 70% acetone, respectively. The total phenolic content in these fractions was determined by the Folin–Ciocalteu method. A combination of LC–MS and MALDI-TOF methods were used to characterize the nature of polyphenolic compounds in the cranberry extracts. High resolution mass spectrometry was used to generate empirical formulae for the detected species. The low molecular weight fraction was essentially constituted of small phenolic acids (hydroxycinnamic and hydroxybenzoic acids). The medium fraction was mostly composed of anthocyanin, flavonols (quercetin, myricetin, isorhamnetin, kaempferol), procyanidins monomers (epicatechin, catechin), dimers, and few small oligomers. The heavy fraction was devoid of phenolic acids and anthocyanins, and it contained for the most part oligomers and polymers of procyanidins. Proanthocyanidins oligomers up to n = 22 were detected, which is, to our knowledge, the largest individual polymers reported to date. With this approach, it was also possible to distinguish between the A-type and B-type linkages.

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Zhang, Lei, Ling-Yan Jiang, Ke Zheng, Hua Duan, Min Li, and Yuan-Chen Cui. "Enzymatic Synthesis of p-Cresol Oligomers and Evaluation of their Free Radical Scavenging Activity." Australian Journal of Chemistry 68, no. 2 (2015): 282. http://dx.doi.org/10.1071/ch13734.

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An environmentally benign aqueous micelle system was successfully used as reaction medium to perform enzymatic polymerization of p-cresol using horseradish peroxidase as catalyst. The polymerization maintains high yield over a wide pH range from 5 to 10. The resulting polymer is completely soluble in common solvent such as acetone, THF, DMF, and DMSO. Infrared spectroscopy analysis shows that polymer chains are composed of phenylene and oxyphenylene units. The formation of p-cresol polymer is according to a mechanism of free radical step polymerization. Because quinone structures are formed at the end of the molecular chain, p-cresol oligomers with an average degree of polymerization of less than 10 are obtained. p-Cresol oligomers possess several advantages such as simple synthetic route, good stability in air, and no significant smell. Importantly, the structure of p-cresol oligomers is similar to that of polyphenolic compounds in natural plants. As a result, p-cresol oligomers show good free radical scavenging activity and good prospects as novel antioxidant.

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Caruana, Mario, Tobias Högen, Johannes Levin, Andreas Hillmer, Armin Giese, and Neville Vassallo. "Inhibition and disaggregation of α-synuclein oligomers by natural polyphenolic compounds." FEBS Letters 585, no. 8 (March 26, 2011): 1113–20. http://dx.doi.org/10.1016/j.febslet.2011.03.046.

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Ono, Kenjiro, Daisy Zhao, Qingli Wu, James Simon, Jun Wang, Aurelian Radu, and Giulio Maria Pasinetti. "Pine Bark Polyphenolic Extract Attenuates Amyloid-β and Tau Misfolding in a Model System of Alzheimer’s Disease Neuropathology1." Journal of Alzheimer's Disease 73, no. 4 (February 18, 2020): 1597–606. http://dx.doi.org/10.3233/jad-190543.

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Plant-derived polyphenolic compounds possess diverse biological activities, including strong anti-oxidant, anti-inflammatory, anti-microbial, and anti-tumorigenic activities. There is a growing interest in the development of polyphenolic compounds for preventing and treating chronic and degenerative diseases, such as cardiovascular disorders, cancer, and neurological diseases including Alzheimer’s disease (AD). Two neuropathological changes of AD are the appearance of neurofibrillary tangles containing tau and extracellular amyloid deposits containing amyloid-β protein (Aβ). Our laboratory and others have found that polyphenolic preparations rich in proanthocyanidins, such as grape seed extract, are capable of attenuating cognitive deterioration and reducing brain neuropathology in animal models of AD. Oligopin is a pine bark extract composed of low molecular weight proanthocyanidins oligomers (LMW-PAOs), including flavan-3-ol units such as catechin (C) and epicatechin (EC). Based on the ability of its various components to confer resilience to the onset of AD, we tested whether oligopin can specifically prevent or attenuate the progression of AD dementia preclinically. We also explored the underlying mechanism(s) through which oligopin may exert its biological activities. Oligopin inhibited oligomer formation of not only Aβ1-40 and Aβ1-42, but also tau in vitro. Our pharmacokinetics analysis of metabolite accumulation in vivo resulted in the identification of Me-EC-O-β-Glucuronide, Me-(±)-C-O-β-glucuronide, EC-O-β-glucuronide, and (±)-C-O-β-glucuronide in the plasma of mice. These metabolites are primarily methylated and glucuronidated C and EC conjugates. The studies conducted provide the necessary impetus to design future clinical trials with bioactive oligopin to prevent both prodromal and residual forms of AD.

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Faleva, Anna V., Nikolay V. Ul’yanovskii, Danil I. Falev, Aleksandra A. Onuchina, Nikolay A. Budaev, and Dmitry S. Kosyakov. "New Oligomeric Dihydrochalcones in the Moss Polytrichum commune: Identification, Isolation, and Antioxidant Activity." Metabolites 12, no. 10 (October 14, 2022): 974. http://dx.doi.org/10.3390/metabo12100974.

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One of the most widespread representatives of mosses in the temperate and boreal latitudes of the Northern Hemisphere is common haircap (Polytrichum commune), which is known as the largest moss in the world and widely used in traditional herbal medicine. Polyphenolic compounds constitute one of the most important groups of biologically active secondary metabolites of P. commune, however, the available information on their chemical composition is still incomplete and contradictory. In the present study, a group of dihydrochalcone polyphenolic derivatives that were not previously found in mosses was isolated from P. commune biomass using pressurized liquid extraction with aqueous acetone. The combination of two-dimensional NMR spectroscopy and high-performance liquid chromatography–high-resolution mass spectrometry allowed for identifying them as 3-hydroxyphloretin oligomers formed through a carbon–carbon bond between phloroglucinol and pyrocatechol moieties (“head-to-tail” coupling), with a polymerization degree of 2–5. The individual compounds isolated by preparative reverse-phase HPLC had a purity of 71 to 97% and demonstrated high radical scavenging activity (17.5–42.5 % with respect to Trolox) determined by the photochemiluminescence method. Along with the low toxicity predicted by QSAR/QSTR algorithms, this makes 3-hydroxyphloretin oligomers a promising source for the production of biologically active food additives and pharmaceuticals.

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Zaidi, Fatima Kamal, and Shashank Deep. "Scutellarin inhibits the uninduced and metal-induced aggregation of α-Synuclein and disaggregates preformed fibrils: implications for Parkinson's disease." Biochemical Journal 477, no. 3 (February 11, 2020): 645–70. http://dx.doi.org/10.1042/bcj20190705.

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The aggregation of the protein alpha synuclein (α-Syn), a known contributor in Parkinson's disease (PD) pathogenesis is triggered by transition metal ions through occupational exposure and disrupted metal ion homeostasis. Naturally occurring small molecules such as polyphenols have emerged as promising inhibitors of α-Syn fibrillation and toxicity and could be potential therapeutic agents against PD. Here, using an array of biophysical tools combined with cellular assays, we demonstrate that the novel polyphenolic compound scutellarin efficiently inhibits the uninduced and metal-induced fibrillation of α-Syn by acting at the nucleation stage and stabilizes a partially folded intermediate of α-Syn to form SDS-resistant, higher-order oligomers (∼680 kDa) and also disaggregates preformed fibrils of α-Syn into similar type of higher-order oligomers. ANS binding assay, fluorescence lifetime measurements and cell-toxicity experiments reveal scutellarin-generated oligomers as compact, low hydrophobicity structures with modulated surface properties and significantly reduced cytotoxicity than the fibrillation intermediates of α-Syn control. Fluorescence spectroscopy and isothermal titration calorimetry establish the binding between scutellarin and α-Syn to be non-covalent in nature and of moderate affinity (Ka ∼ 105 M−1). Molecular docking approaches suggest binding of scutellarin to the residues present in the NAC region and C-terminus of monomeric α-Syn and the C-terminal residues of fibrillar α-Syn, demonstrating inhibition of fibrillation upon binding to these residues and possible stabilization of the autoinhibitory conformation of α-Syn. These findings reveal interesting insights into the mechanism of scutellarin action and establish it as an efficient modulator of uninduced as well as metal-induced α-Syn fibrillation and toxicity.

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Maisto, Maria, Elisabetta Schiano, Ettore Novellino, Vincenzo Piccolo, Fortuna Iannuzzo, Emanuela Salviati, Vincenzo Summa, Giuseppe Annunziata, and Gian Carlo Tenore. "Application of a Rapid and Simple Technological Process to Increase Levels and Bioccessibility of Free Phenolic Compounds in Annurca Apple Nutraceutical Product." Foods 11, no. 10 (May 17, 2022): 1453. http://dx.doi.org/10.3390/foods11101453.

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Insoluble bound polyphenols (ISBP) are polyphenolic compounds linked to the food matrix with different interactions limiting both their water extractability and consequent bioaccessibility. The health-promoting potential of polyphenols is historically known and well-demonstrated; specifically, Annurca apple polyphenols were studied both in vitro and in vivo for their effect in controlling cholesterol plasma levels. The aim of the study was the preparation of nutraceutical products based on Annurca apple polyphenolic fraction through the application of a technological process (acid treatment) able to release the ISBP from Annurca apple food matrix and increase polyphenol bioaccessibility. Lyophilized annurca apple (LAA) underwent acid treatment (ATLAA), and differences in released polyphenol levels were analysed by DAD-HPLC. Free-polyphenol levels in samples treated under acid conditions were higher than in untreated ones; in particular, for oligomeric flavan-3-ols (+168% procyanidin B2, +42.97% procyanidin B1 and B2, +156.99% procyanidin C1), catechin (+512.20%), and gallic acid (+707.77%). Furthermore, ATLAA underwent an in vitro gastrointestinal digestion to evaluate the bioaccessibility of contained polyphenols, in comparison to the untreated Annurca apple. The bioaccessibility study indicates a valuable preservation of polyphenolic fraction compared to the control.

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Di Gennaro, Patrizia, Valentina Sabatini, Silvia Fallarini, Roberto Pagliarin, and Guido Sello. "Polyphenol Polymerization by an Alternative Oxidative Microbial Enzyme and Characterization of the Biological Activity of Oligomers." BioMed Research International 2018 (2018): 1–10. http://dx.doi.org/10.1155/2018/3828627.

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The recombinant catalase-peroxidase HPI from E. coli was used as an alternative enzyme in polymerization reactions for the production of (−) epicatechin oligomers and their biological activity was characterized. The enzyme was prepared in two forms: a purified and an immobilized form. Both were tested for their activity in oxidative polymerization reactions, and their stability and reusability were assessed. The polymerization reactions were followed by SEC-HPLC analyses, and the substrate was completely converted into one or more polymerization products depending on the reactions conditions. Results showed that the utilized conditions allowed for the isolation of some oligomers of different molecular weight: the oligomers containing 6 and 7 units of epicatechin substrate are the heaviest ones. Epicatechin was also used in reactions catalyzed by HRP in the same reaction conditions for comparison. In addition, one selected oligomer obtained by HPI enzyme catalysis was shown to act as in vitro inhibitor of tumor cell growth, like one oligomer deriving from epicatechin by HRP catalysis. These data confirm that epicatechin oligomeric form is more effective than its monomer in biological activity and suggest the use of HPI as an alternative enzyme in reactions for the production of epicatechin oligomers.

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Yoshikawa, Shinji, Lih-Geeng Chen, Morio Yoshimura, Yoshiaki Amakura, Tsutomu Hatano, and Shoko Taniguchi. "Barricyclin D1—a dimeric ellagitannin with a macrocyclic structure—and accompanying tannins from Barringtonia racemosa." Bioscience, Biotechnology, and Biochemistry 85, no. 7 (April 23, 2021): 1609–20. http://dx.doi.org/10.1093/bbb/zbab073.

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ABSTRACT Our examination of high molecular weight polyphenolic constituents in the leaves of Barringtonia racemosa of the family Lecythidaceae uncovered 5 previously undescribed ellagitannins. One, barringtin M1 (1), among them was a hydrolysable tannin monomer, while remaining 4, barringtins D1 (2), D2 (3), D3 (4), and barricyclin D1 (5), were all dimers. Barricyclin D1 had a first macrocyclic structure formed from casuarictin (6) and tellimagrandin I (7), and the other ellagitannins had structures related to 5. Two additional known phenolics, valoneic acid dilactone (8) and schimawalin A (9), were also isolated from the leaves. These results suggested that the leaves of B. racemosa are a natural resource rich in hydrolysable tannin oligomers.

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Valcheva-Kuzmanova, Stefka V., Petko N. Denev, and Manol H. Ognyanov. "Chemical Composition and Antioxidant Activity of Chaenomeles Maulei Fruit Juice." Journal of Biomedical and Clinical Research 11, no. 1 (July 1, 2018): 41–48. http://dx.doi.org/10.2478/jbcr-2018-0007.

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Summary Chaenomeles maulei is the name of the cultivar of Chaenomeles japonica, which was introduced in Europe. The present study aimed to investigate the chemical composition and the antioxidant activity of Chaenomeles maulei fruit juice (CMFJ). The ingredients of the juice sample were measured by spectrophotometric, high-performance liquid chromatography (HPLC) and gravimetric methods. The antioxidant activity was measured by the oxygen radical absorbance capacity (ORAC) and hydroxyl radical averting capacity (HORAC) assays. The results showed that CMFJ was extremely rich in polyphenolic substances, amongst which the highest was the concentration of procyanidin oligomers, followed by phenolic acids (vanillic > caffeic > chlorogenic > neochlorogenic > p-coumaric > ellagic > ferulic > 4-dihydroxy-benzoic) and flavonoids (epicatechin > catechin > quercetin-3-β-glucoside > quercetin > rutin > naringin > kaempferol > myricetin). The sour taste of the juice and its low pH were due to the high content of organic acids (malic > quinic > citric > shikimic > ascorbic > oxalic). The carbohydrates were presented by glucose > fructose > galactose > xylose > rhamnose > arabinose. The antioxidant activity measured by ORAC and HORAC was very high. It could be attributed to the high content of polyphenolics in the juice.

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Ladiwala, Ali Reza A., Mauricio Mora-Pale, Jason C. Lin, Shyam Sundhar Bale, Zachary S. Fishman, Jonathan S. Dordick, and Peter M. Tessier. "Polyphenolic Glycosides and Aglycones Utilize Opposing Pathways To Selectively Remodel and Inactivate Toxic Oligomers of Amyloid β." ChemBioChem 12, no. 11 (June 10, 2011): 1749–58. http://dx.doi.org/10.1002/cbic.201100123.

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Mallet, Jean-François, Roghayeh Shahbazi, Nawal Alsadi, Ammar Saleem, Agnes Sobiesiak, John Thor Arnason, and Chantal Matar. "Role of a Mixture of Polyphenol Compounds Released after Blueberry Fermentation in Chemoprevention of Mammary Carcinoma: In Vivo Involvement of miR-145." International Journal of Molecular Sciences 24, no. 4 (February 12, 2023): 3677. http://dx.doi.org/10.3390/ijms24043677.

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Epigenetic mechanisms such as microRNA (miRNA) deregulation seem to exert a central role in breast cancer initiation and progression. Therefore, targeting epigenetics deregulation may be an effective strategy for preventing and halting carcinogenesis. Studies have revealed the significant role of naturally occurring polyphenolic compounds derived from fermented blueberry fruits in cancer chemoprevention by modulation of cancer stem cell development through the epigenetic mechanism and regulation of cellular signaling pathways. In this study, we first investigated the phytochemical changes during the blueberry fermentation process. Fermentation favored the release of oligomers and bioactive compounds such as protocatechuic acid (PCA), gallic acid, and catechol. Next, we investigated the chemopreventive potentials of a polyphenolic mixture containing PCA, gallic acid, and catechin found in fermented blueberry juice in a breast cancer model by measuring miRNA expression and the signaling pathways involved in breast cancer stemness and invasion. To this end, 4T1 and MDA-MB-231 cell lines were treated with different doses of the polyphenolic mixture for 24 h. Additionally, female Balb/c mice were fed with this mixture for five weeks; two weeks before and three weeks after receiving 4T1 cells. Mammosphere formation was assayed in both cell lines and the single-cell suspension obtained from the tumor. Lung metastases were counted by isolating 6-thioguanine-resistant cells present in the lungs. In addition, we conducted RT-qPCR and Western blot analysis to validate the expression of targeted miRNAs and proteins, respectively. We found a significant reduction in mammosphere formation in both cell lines treated with the mixture and in tumoral primary cells isolated from mice treated with the polyphenolic compound. The number of colony-forming units of 4T1 cells in the lungs was significantly lower in the treatment group compared to the control group. miR-145 expression significantly increased in the tumor samples of mice treated with the polyphenolic mixture compared to the control group. Furthermore, a significant increase in FOXO1 levels was noted in both cell lines treated with the mixture. Overall, our results show that phenolic compounds found in fermented blueberry delay the formation of tumor-initiating cells in vitro and in vivo and reduce the spread of metastatic cells. The protective mechanisms seem to be related, at least partly, to the epigenetic modulation of mir-145 and its signaling pathways.

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Wang, Yan, Zheng Xia, Jian-Rong Xu, Yan-Xia Wang, Li-Na Hou, Yu Qiu, and Hong-Zhuan Chen. "α-Mangostin, a polyphenolic xanthone derivative from mangosteen, attenuates β-amyloid oligomers-induced neurotoxicity by inhibiting amyloid aggregation." Neuropharmacology 62, no. 2 (February 2012): 871–81. http://dx.doi.org/10.1016/j.neuropharm.2011.09.016.

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Dufour, Cécile, Jose A. Villa-Rodriguez, Christophe Furger, Jacob Lessard-Lord, Camille Gironde, Mylène Rigal, Ashraf Badr, Yves Desjardins, and Denis Guyonnet. "Cellular Antioxidant Effect of an Aronia Extract and Its Polyphenolic Fractions Enriched in Proanthocyanidins, Phenolic Acids, and Anthocyanins." Antioxidants 11, no. 8 (August 12, 2022): 1561. http://dx.doi.org/10.3390/antiox11081561.

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Oxidative stress and chronic inflammation contribute to some chronic diseases. Aronia berries are rich in polyphenols. The aim of the present study was to characterize the cellular antioxidant effect of an aronia extract to reflect the potential physiological in vivo effect. Cellular in vitro assays in three cell lines (Caco-2, HepG2, and SH-SY5Y) were used to measure the antioxidant effect of AE, in three enriched polyphenolic fractions (A1: anthocyanins and phenolic acids; A2: oligomeric proanthocyanidins; A3: polymeric proanthocyanidins), pure polyphenols and microbial metabolites. Both direct (intracellular and membrane radical scavenging, catalase-like effect) and indirect (NRF2/ARE) antioxidant effects were assessed. AE exerted an intracellular free radical scavenging activity in the three cell lines, and A2 and A3 fractions showed a higher effect in HepG2 and Caco-2 cells. AE also exhibited a catalase-like activity, with the A3 fraction having a significant higher activity. Only A1 fraction activated the NRF2/ARE pathway. Quercetin and caffeic acid are the most potent antioxidant polyphenols, whereas cyanidin and 5-(3′,4′-dihydroxyphenyl)-γ-valerolactone showed the highest antioxidant effect among polyphenol metabolites. AE rich in polyphenols possesses broad cellular antioxidant effects, and proanthocyanidins are major contributors. Polyphenol metabolites may contribute to the overall antioxidant effect of such extract in vivo.

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Arraki, Kamel, Perle Totoson, Alain Decendit, Andy Zedet, Justine Maroilley, Alain Badoc, Céline Demougeot, and Corine Girard. "Mammalian Arginase Inhibitory Activity of Methanolic Extracts and Isolated Compounds from Cyperus Species." Molecules 26, no. 6 (March 18, 2021): 1694. http://dx.doi.org/10.3390/molecules26061694.

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Polyphenolic enriched extracts from two species of Cyperus, Cyperus glomeratus and Cyperus thunbergii, possess mammalian arginase inhibitory capacities, with the percentage inhibition ranging from 80% to 95% at 100 µg/mL and 40% to 64% at 10 µg/mL. Phytochemical investigation of these species led to the isolation and identification of two new natural stilbene oligomers named thunbergin A-B (1–2), together with three other stilbenes, trans-resveratrol (3), trans-scirpusin A (4), trans-cyperusphenol A (6), and two flavonoids, aureusidin (5) and luteolin (7), which were isolated for the first time from C.thunbergii and C. glomeratus. Structures were established on the basis of the spectroscopic data from MS and NMR experiments. The arginase inhibitory activity of compounds 1–7 was evaluated through an in vitro arginase inhibitory assay using purified liver bovine arginase. As a result, five compounds (1, 4–7) showed significant inhibition of arginase, with IC50 values between 17.6 and 60.6 µM, in the range of those of the natural arginase inhibitor piceatannol (12.6 µM). In addition, methanolic extract from Cyperus thunbergii exhibited an endothelium and NO-dependent vasorelaxant effect on thoracic aortic rings from rats and improved endothelial dysfunction in an adjuvant-induced arthritis rat model.

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Benmeziane, Farida, and Yves Cadot. "Quantitative analysis of proanthocyanidins (tannins) from cardinal grape (Vitis vinifera) skin and seed by RP-HPLC." North African Journal of Food and Nutrition Research 3, no. 6 (November 16, 2019): 201–5. http://dx.doi.org/10.51745/najfnr.3.6.201-205.

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Background: Grape phenolics are structurally diverse, from simple molecules to oligomers and polymers usually designated “tannins or proanthocyanidins (PAs)” referring to their ability to interact with proteins. Those compounds have been attributed to a great number of biological activities beneficial for human health as they act as antioxidant, anti-inflammatory, antitumor, etc. Aim: The objective of the current study was to quantify and to identify the PAs and determine the mean degree of polymerization (DPm) in seeds and skins of the grape cardinal variety cultivated in El-Tarf region, Algeria. Methods and Material: To determine PAs, Reverse Phase High-Performance Liquid Chromatography with Diode Array Detection (RP-HPLC-DAD) has been utilized. The DPm was determined after the reaction of thiolysis in the presence of toluene-α-thiol reagent. Results: HPLC-DAD analysis of Cardinal skin and seed extract showed that epicatechin gallate (ECG) and epigallocatechin (EGC) were the major constitutive units of grape skin tannins and the mean degree of polymerization (DPm) was lower for seed PAs than for skin. Conclusions: This study showed the richness of skin and grape seeds in polyphenolic compounds (PAs). Therefore, these parts of grape can be used as a potential source of bioactive molecules to promote the health of populations in this region in Algeria. Keywords: Grape, Skin, Seed, Proanthocyanidins, RP-HPLC-DAD.

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Ochoa-Meza, Laura Celina, Eber Addí Quintana-Obregón, Irasema Vargas-Arispuro, Alejandro Bernardo Falcón-Rodríguez, Emmanuel Aispuro-Hernández, José J. Virgen-Ortiz, and Miguel Ángel Martínez-Téllez. "Oligosaccharins as Elicitors of Defense Responses in Wheat." Polymers 13, no. 18 (September 15, 2021): 3105. http://dx.doi.org/10.3390/polym13183105.

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Wheat is a highly relevant crop worldwide, and like other massive crops, it is susceptible to foliar diseases, which can cause devastating losses. The current strategies to counteract wheat diseases include global monitoring of pathogens, developing resistant genetic varieties, and agrochemical applications upon diseases’ appearance. However, the suitability of these strategies is far from permanent, so other alternatives based on the stimulation of the plants’ systemic responses are being explored. Plants’ defense mechanisms can be elicited in response to the perception of molecules mimicking the signals triggered upon the attack of phytopathogens, such as the release of plant and fungal cell wall-derived oligomers, including pectin and chitin derivatives, respectively. Among the most studied cell wall-derived bioelicitors, oligogalacturonides and oligochitosans have received considerable attention in recent years due to their ability to trigger defense responses and enhance the synthesis of antipathogenic compounds in plants. Particularly, in wheat, the application of bioelicitors induces lignification and accumulation of polyphenolic compounds and increases the gene expression of pathogenesis-related proteins, which together reduce the severity of fungal infections. Therefore, exploring the use of cell wall-derived elicitors, known as oligosaccharins, stands as an attractive option for the management of crop diseases by improving plant readiness for responding promptly to potential infections. This review explores the potential of plant- and fungal-derived oligosaccharins as a practical means to be implemented in wheat crops.

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Rezaei, Zahra, and Amir siahpoosh. "Evaluation and comparison of the antioxidant activity of extractable and non-extractable polyphenols of sour orange peel." Jundishapur Journal of Medical Sciences 20, no. 6 (March 6, 2022): 10. http://dx.doi.org/10.32598/jsmj.20.6.2133.

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Purpose: Research on food polyphenols has experienced a huge development during the last century. Most studies on polyphenolic compounds have focused on extractable portions. However, an important polyphenolic fraction is ignored (non-extractable polyphenols) because they are trapped in the corresponding extraction residues. In this study, the antioxidant activity of extractable and non-extractable polyphenols of orange peel, extracted by aqueous solvent and acid hydrolysis (with two different solvent systems) respectively, are evaluated and compared. Method: Antioxidant activity was evaluated by four tests of radical inhibition of 2, 2-diphenyl-1-picrylhydrazyl (DPPH), 2, 2-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS), ferric reducing antioxidant power (FRAP) and iron chelating. The amount of polyphenolic compounds, flavonoids, oligomeric proanthocyanidins, and flavanones were respectively determined by folin-ciocalteu, AlCl3 and UV-visible spectrophotometer. Also, the anti-lipid peroxidation effect in rat liver was measured. Results: The results of antioxidant analysis showed that non-extractable polyphenolic extract, which extracted by methanol / sulfuric acid solvent had the highest level of antioxidant activity in sour orange peel. It can be due to the high polyphenolic compounds in this extraction compared to the others. Conclusion: All extracts had antioxidant activity and can be suggested as a potential natural source in food and pharmaceutical industries.

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La Mantia, Alessandro, Federica Ianni, Aurélie Schoubben, Marco Cespi, Klemen Lisjak, Davide Guarnaccia, Roccaldo Sardella, and Paolo Blasi. "Effect of Cocoa Roasting on Chocolate Polyphenols Evolution." Antioxidants 12, no. 2 (February 13, 2023): 469. http://dx.doi.org/10.3390/antiox12020469.

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Cocoa and chocolate antioxidants might contribute to human health through, for instance, blood flow improvement or blood pressure and glycemia reduction, as well as cognitive function improvement. Unfortunately, polyphenol content is reduced during cocoa fermentation, drying, roasting and all the other phases involved in the chocolate production. Here, we investigated the evolution of the polyphenol content during all the different steps of chocolate production, with a special emphasis on roasting (3 different roasting cycles with 80, 100, and 130 °C as maximum temperature). Samples were followed throughout all processes by evaluating the total polyphenols content, the antioxidant power, the epicatechin content, and epicatechin mean degree of polymerization (phloroglucinol adducts method). Results showed a similar trend for total polyphenol content and antioxidant power with an unexpected bell-shaped curve: an increase followed by a decrease for the three different roasting temperatures. At the intermediate temperature (100 °C), the higher polyphenol content was found just after roasting. The epicatechin content had a trend similar to that of total polyphenol content but, interestingly, the mean degree of polymerization data had the opposite behavior with some deviation in the case of the highest temperature, probably due to epicatechin degradation. It seems likely that roasting can free epicatechin from oligomers, as a consequence of oligomers remodeling.

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Leri, Manuela, Andrea Bertolini, Massimo Stefani, and Monica Bucciantini. "EVOO Polyphenols Relieve Synergistically Autophagy Dysregulation in a Cellular Model of Alzheimer’s Disease." International Journal of Molecular Sciences 22, no. 13 (July 5, 2021): 7225. http://dx.doi.org/10.3390/ijms22137225.

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(1) Background: Autophagy, the major cytoplasmic process of substrate turnover, declines with age, contributing to proteostasis decline, accumulation of harmful protein aggregates, damaged mitochondria and to ROS production. Accordingly, abnormalities in the autophagic flux may contribute to many different pathophysiological conditions associated with ageing, including neurodegeneration. Recent data have shown that extra-virgin olive oil (EVOO) polyphenols stimulate cell defenses against plaque-induced neurodegeneration, mainly, through autophagy induction. (2) Methods: We carried out a set of in vitro experiments on SH-SY5Y human neuroblastoma cells exposed to toxic Aβ1–42 oligomers to investigate the molecular mechanisms involved in autophagy activation by two olive oil polyphenols, oleuropein aglycone (OleA), arising from the hydrolysis of oleuropein (Ole), the main polyphenol found in olive leaves and drupes and its main metabolite, hydroxytyrosol (HT). (3) Results: Our data show that the mixture of the two polyphenols activates synergistically the autophagic flux preventing cell damage by Aβ1–42 oligomers., in terms of ROS production, and impairment of mitochondria. (4) Conclusion: Our results support the idea that EVOO polyphenols act synergistically in autophagy modulation against neurodegeneration. These data confirm and provide the rationale to consider these molecules, alone or in combination, as promising candidates to contrast ageing-associated neurodegeneration.

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Lachman, J., E. C. Fernández, and M. Orsák. "Yacon [Smallanthus sonchifolia (Poepp. et Endl.) H. Robinson] chemical composition and use – a review." Plant, Soil and Environment 49, No. 6 (December 10, 2011): 283–90. http://dx.doi.org/10.17221/4126-pse.

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Yacon [Smallanthus sonchifolia (Poepp. et Endl.) H. Robinson], a native plant of the Andes, belongs to the family Compositae (Asteraceae) and it represents a traditional crop of the original population of Peru used in traditional medicine. A major portion of tuberous root biomass is composed of water (> 70% of fresh weight). Saccharides, especially oligo-fructans, form 70–80% of dry weight, protein content ranges between 0.3% and 3.7%. Fructooligosaccharides of inulin type b (2®1), mainly oligomers (GF2–GF16), are known for their ability to keep the colon healthy. Yacon sweetness is predominantly caused by fructose, which is by some 70% sweeter than sucrose. Other oligosaccharides are 1-kestose and nystose. Diabetics and persons suffering from digestive problems are recommended to consume yacon because its sugars are not available from the small intestine. The mean tuberous root composition per 100 g of fresh matter is 81.3, 13.8, 0.9, 1.0, 0.1 and 1.1 g of water, saccharides, fibre, proteins, lipids and ash, respectively. Mean mineral contents per 100 g of fresh matter are 334, 34, 12, 8.4, 0.4 and 0.2 mg of potassium, phosphorus, calcium, magnesium, sodium and iron, respectively. Vitamins B1, B2, C, b-carotene and polyphenols in the same weight are present at mean concentrations 0.07, 0.31, 5.0, 0.13 and 203 mg, respectively. Yacon can be considered an industrial crop, particularly as a source of inulin. The used forms are flour, syrup, extract from tuberous roots and moreover leaf extract for the preparation of yacon infusion with hypoglycaemic effect. In yacon leaves di- and sesquiterpenes with protective effects against insects are present, among them mainly ent-kaurenic acid (ent-kaur-16-en-19-oic acid) and its derivative – 15-a-angeloyloxy-ent-kauren-19-oic acid 16-epoxide. Other components are polyphenolic antioxidants, esp. hydroxycinnamic acids and chlorogenic acid. A new antifungal melampolide – sesquiterpene lactone named sonchifolin, as well as three known melampolides, polymatin B, uvedalin and enhydrin, were isolated from leaf extracts of yacon. Three major phytoalexins were isolated: 4’-hydroxy-3’-(3-methylbutanoyl)acetophenone, 4’-hydroxy-3’-(3-methyl-2-butenyl)acetophenone and 5-acetyl-2-(1-hydroxy-1-methylethyl)benzofuran.

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Utami, Ratri Retno. "ANTIOKSIDAN BIJI KAKAO: PENGARUH FERMENTASI DAN PENYANGRAIAN TERHADAP PERUBAHANNYA (ULASAN)." Jurnal Industri Hasil Perkebunan 13, no. 2 (December 28, 2018): 75–85. http://dx.doi.org/10.33104/jihp.v13i2.4062.

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The main cocoa antioxidant compounds are flavanols that consist of monomer (epicatechin and catechin) and oligomers from dimers to decamers (procyanidin), with small quantity of anthocyanin (cyaniding glucoside) and flavonol (quercetin glycoside). Cocoa processing stages that affect antioxidant compounds changes atre fermentation and roasting. Fermentation causes decrease of polyphenol content due to polyphenols diffusion out of the cotyledons, furthermore polyphenols undergo oxidation and condensation. Roasting temperature more than 70oC cause loss of (+)-catechin. During roasting, protein that bounded to the cell wall (cellulose and pectin) undergo Maillard reaction where its products potentially as antioxidants. This study is useful to know the proper of cocoa beans processing so antioxidant content can be maximized.

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Pico-Hernández, Sergio M., Cristian J. Murillo-Méndez, and Luis J. López-Giraldo. "Extraction, separation, and evaluation of antioxidant effect of the different fractions of polyphenols from cocoa beans." Revista Colombiana de Química 49, no. 3 (November 6, 2020): 19–27. http://dx.doi.org/10.15446/rcq.v49n3.84082.

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Polyphenol Extracts (PE) hold antioxidant properties, which might be related to positive effects on human health. It has been stated that PE, obtained from cocoa beans, contain fractions of flavan-3-ols with different degrees of polymerization (DP). However, it is unknown which of the fractions or their mixture drives the best antioxidant activity. This paper reports the study conducted to elucidate the role of each fraction (with different DP) on Antioxidant Capacity (AC). First, the process of extraction and separation of polyphenols’ fractions in cocoa beans was executed; afterward, AC was determined for each fraction individually and their combinations (monomers, dimers and oligomers). Solid-liquid extraction was made by using a 50% (v/v) ethanol solution and a mass:solvent ratio of 1:120 in an ultrasound bath. PE were separated into monomers, dimers, and oligomers by HPLC using a semipreparative column. The results obtained show that PE contain 95.35, 7.45, and 21.75 mg EE (epicatechin equivalents) / g ds of monomers, dimers, and oligomers, respectively. Finally, the AC of each fraction was evaluated using a complete cubic model mix design. According to the results, the best AC was obtained for dimers. However, when monomers, dimers and oligomers were mixed, an antagonistic effect on AC was observed.

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Natsume, Midori. "Polyphenols: Inflammation." Current Pharmaceutical Design 24, no. 2 (April 5, 2018): 191–202. http://dx.doi.org/10.2174/1381612823666171109104141.

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Background: Polyphenols widely distributed in plants, fruits and vegetables have received considerable attention on account of their physiological functions, including their antioxidant and anti-inflammatory properties. Some antioxidant components of cacao liquor prepared from fermented and roasted cacao beans, which is a major ingredient of cocoa and chocolate products, have been characterized as flavan-3-ols and procyanidin oligomers. Methods: This review focuses on a specific group of (-)-epicatechins and their oligomers, the procyanidins, in cacao products. Dietary polyphenols in cacao products have been shown to reduce hypertension, reduce platelet aggregation, improve serum lipids, and lower the incidence of atherosclerosis in animal studies and clinical trials. Conclusion: The intake of cacao products reduces hypertension and atherosclerosis on account of their physiological functions as antioxidants and anti-inflammation agents, indicating the mechanisms of prevention of hypertension and atherosclerosis by polyphenols.

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Fedorova, Tat'yana Yevgen'yevna, Sergey Vladimirovich Fedorov, and Vasily Anatolyevich Babkin. "PHENOLIC COMPOUNDS OF CEDAR WOOD (SIBERIAN PINE) PINUS SIBIRICA DU TOUR." chemistry of plant raw material, no. 3 (October 22, 2020): 97–104. http://dx.doi.org/10.14258/jcprm.2020037329.

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As part of the study of extractives of biomass of coniferous trees of Siberia in order to predict the possibility of obtaining valuable biologically active products, a study was conducted of the chemical composition of the ethyl acetate extract of cedar wood (Siberian pine) Pinus sibirica Du Tour. The chemical composition of the phenolic compounds of cedar wood was studied, including the structure of oligomeric polyphenols. The yields of extractives extracted with ethyl acetate and water from cedar wood were 1.6 and 2.71% of a.s. (absolutely dry matter). The content of phenolic compounds in the ethyl acetate extract of cedar wood was 45.9% rel. Based on 1H and 13C NMR spectroscopy data, it was found that the main monomeric phenolic extractive substances of cedar wood are stilbene – pinosilvin monomethyl ether (content in cedar wood 0.25% of a.s.) and flavonoids – tectochrizin, pinocembrin, and pinobankxin, as well as oligomeric and polymeric phenolic compounds. It was shown that the composition of cedar wood oligomers includes a complex mixture of stilbene derivatives of pinosilvin and flavonoids with the inclusion of carbohydrate residues. The content of the fraction of oligomeric and polymeric phenolic compounds in cedar wood is 0.39% of a.s.

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Matos, Ana M., Joana S. Cristóvão, Dmitry V. Yashunsky, Nikolay E. Nifantiev, Ana S. Viana, Cláudio M. Gomes, and Amélia P. Rauter. "Synthesis and effects of flavonoid structure variation on amyloid-β aggregation." Pure and Applied Chemistry 89, no. 9 (August 28, 2017): 1305–20. http://dx.doi.org/10.1515/pac-2017-0201.

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AbstractDietary flavonoids and synthetic derivatives have a well-known potential for biomedical applications. In this perspective, we report herein new methodologies to access chrysin and 5,7-dihydroxychromone, and these structures were combined with those of naturally occurring quercetin, luteolin, (+)-dihydroquercetin and apigenin to assemble a set of polyphenols with structure variations for in vitro testing over the aggregation of Alzheimer’s disease (AD) amyloid peptide Aβ1−42. Using thioflavin-T (ThT) monitored kinetics and subsequent mechanistic analysis by curve fitting, we show that catechol-type flavonoids reduce Aβ1−42 fibril content by 30% at molar ratios over 10. Without affecting secondary nucleation, these compounds accelerate primary nucleation events responsible for early primary oligomer formation, putatively redirecting the latter into off-pathway aggregates. Atomic force microscopy (AFM) imaging of reaction end-points allowed a comprehensive topographical analysis of amyloid aggregate populations formed in the presence of each compound. Formation of Aβ1−42 small oligomers, regarded as the most toxic amyloid structures, seems to be limited by flavonoids with a C2 phenyl group, while flavonol 3-OH is not a beneficial structural feature. Overall, the diversity of structural variations within flavonoids opens avenues for their development as chemical tools in the treatment of AD by tackling the formation and distribution of neurotoxic oligomers species.

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Chernousova, Inna Vladimirovna, Viktoriya Yevgen'yevna Mosolkova, Grigoriy Pavlovich Zaitsev, Yuriy Vladimirovich Grishin, Tat'yana Aleksandrovna Zhilyakova, and Yuriy Alekseyevich Ogay. "GRAPE BUNCH POLYPHENOLS, QUALITATIVE AND QUANTITATIVE COMPOSITION, TECHNOLOGICAL STOCK." chemistry of plant raw material, no. 3 (September 26, 2022): 291–300. http://dx.doi.org/10.14258/jcprm.2022039811.

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The Magarach Institute has been addressing the issue of developing technologies for obtaining functional food products from grapes saturated with grape polyphenols; and of determining main properties and modes of grape polyphenol extraction from potential raw materials (pomace, seeds, crests) for the production of experimental samples of functional products. The aim of the present research was not only to experimentally determine the total stock of polyphenols in pomace, seeds, crests of red and white grape varieties, but also to assess empirically the qualitative and quantitative composition of total polyphenols in pomace, seeds, stems, vines, leaves of red and white grape varieties as functional components of a healthy nutrition. The research has dwelled upon the empiric assessment of the characteristics of grape raw materials (grape must, pomace, seeds, crests) in terms of their technological stock, quantitative and qualitative composition of polyphenols (by HPLC), and the main functional ingredients of the biological activity of grape products. An analysis of the data obtained shows that the aqueous-alcoholic extracts of grape raw materials possess the whole spectrum of polyphenols typical for red grape wines (anthocyanins, flavones, flavan-3-ols, hydroxycinnamic, hydroxybenzoic acids, stilbenes, oligomeric and polymeric procyanidins), however their concentration quantitatively exceeds that found in wines. It has been shown that the total content of water-soluble antioxidants experimentally determined by the amperometric method depends on the content of oligomeric and polymeric procyanidins in the extracts of grape raw materials. Thus, the content of oligomeric procyanidins in the extracts of grape raw materials from the sum of phenolic substances averaged 5.7%; while the content of polymer procyanides went up to 94%. The technological availability of polyphenols of pomace, stalks and grape seeds during water-alcohol extraction in the piled layer without mixing was shown, the equilibrium concentrations of polyphenols transferred into the extract and the potential amounts of polyphenols extracted during single-stage extraction (technological stock) were assessed. The maximum values of technological stock of polyphenols of 29.2–76.02 g/kg dry weight in the stalks of white and red grape varieties were determined.

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Matei, Petruta, Beatrice Iacomi, Jesús Martín-Gil, Eduardo Pérez-Lebeña, M. Ramos-Sánchez, M. Barrio-Arredondo, and Pablo Martín-Ramos. "In Vitro Antifungal Activity of Composites of AgNPs and Polyphenol Inclusion Compounds against Fusarium culmorum in Different Dispersion Media." Agronomy 8, no. 11 (October 28, 2018): 239. http://dx.doi.org/10.3390/agronomy8110239.

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Fusarium culmorum is a soil-borne fungus able to cause Fusarium head blight, one of the most important cereal diseases worldwide, which can result in significant yield losses of up to 50% and which jeopardizes food and feed safety due to the mycotoxins produced. In the study presented herein, the enhancement of the antifungal activity against this pathogen, resulting from the addition of silver nanoparticles (AgNPs) to different polyphenol-stevioside inclusion compounds, dispersed either in a chitosan oligomers hydroalcoholic solution or in a choline chloride:urea:glycerol deep eutectic solvent, was investigated in vitro. The polyphenols assayed were curcumin, ferulic acid, gallic acid and silymarin. Four composite concentrations (62.5, 125, 250 and 500 µg·mL−1), with and without AgNPs, were assessed, finding noticeable differences in mycelial growth inhibition, with EC50 and EC90 values ranging from 118 to 579 µg·mL−1 and from 333 to 2604 µg·mL−1, respectively. The obtained results evidenced the improved efficacy of the composites with AgNPs, a superior performance of the composites based on curcumin and ferulic acid, and the advantages of the deep eutectic solvent-based dispersion medium over the chitosan oligomers-based one. The reported composites hold promise for crop protection applications.

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Zongo, Luc, and Heiko Lange. "Lignins and their potential for use as biopolymers in pharmaceutical engineering - a review." Journal Africain de Technologie Pharmaceutique et Biopharmacie (JATPB) 1, no. 1 (October 21, 2022): 37–62. http://dx.doi.org/10.57220/jatpb.v1i1.10.

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Nature offers a diverse set of renewable biopolymers, among them the variety of natural polyphenols, whose structural diversity provides opportunities for further manipulation like the generation of chemicals and novel functional materials. These land‑based renewable biomaterials exhibit also a wide range of heterogeneous intrinsic reactivities and activities that render them ideal starting oligomeric and polymeric materials for the generation of multifunctional supramolecular structures as well as the development of high value-added materials. Lignins in particular display a variety of common physico‑chemical features that can be of enormous interest with respect to their eventual use in the pharmaceutical area. These natural polyphenols possess some interesting pharmaceutical properties such as antioxidant, anti‑inflammatory, antibacterial and eventually antiviral activities. In addition, based on their chemical features, i.e., oligomers and/or polymers of monolignol C9-building blocks. lignins can be exploited in the pharmaceutical sector mainly as material for generation of matrices and carriers for drug delivery. The present work attempts a review of the state of the art in lignin use in pharmaceutical applications. Keywords biopolymers, lignins, microcapsules, nanoparticles, renewable resources

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Jin, Lei, Daemyoung Yun, Wei Zhang, Jinsung Lee, Hongchul Shin, Donghyuk Kim, Tae-Bong Kang, Hyung-Sik Won, Hohyoun Jang, and Whangi Kim. "Polyphenols Coordinated with Cu (II) in an Aqueous System Build ion-Channel Coatings on Hair Surfaces." Materials 16, no. 4 (February 4, 2023): 1333. http://dx.doi.org/10.3390/ma16041333.

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Recently, developments in the field of cosmetics have led to a renewed interest in hair dyeing. However, damage to the hair during the dyeing process has increased hesitation in attempting hair dyeing. As a result, hair dyes with minimal side effects have been in constant demand, and are being developed. In this study, natural-extract polyphenols, pyrogallol, and gallic acid are coordinated by CuCl2 in a NaCl aqueous solution to form an oligomer, which creates an ion-channel coating on the hair surface to protect it. This work attempts to develop fast, simple, and damage-free hair-dye ingredients based on pyrogallol and gallic acid. The morphology and elements of polyphenols coated on hair are characterized. The results reveal that the hair is dyed with the polyphenol-based dye reagent successfully. Moreover, the thickness of the dyed hair continuously rises ten times after dyeing. The tensile strength of the dyed hair is also measured, showing an upward and downward trend. These results reflect the fact that pyrogallol and gallic acid are considered to be the essential and functional polyphenols, and can build ion blocks on hair, which can create new multifunctional coating materials.

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Orozco-Flores, Laura A., Erika Salas, Guillermo González-Sánchez, David Chávez-Flores, Raúl A. Ramírez-García, Beatriz A. Rocha-Gutiérrez, María Del R. Peralta-Pérez, and María De L. Ballinas-Casarrubias. "Novel Zero Headspace Solid-Liquid Extraction for the Recovery of Polyphenolic Fractions from Grape Pomace." Processes 10, no. 6 (June 2, 2022): 1112. http://dx.doi.org/10.3390/pr10061112.

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Grape pomace (GP) is a good source of high-value compounds as up to 60% of grape polyphenols remain in it after wine-making. To overcome traditional membrane technologies’ d rawbacks, such as fouling, a novel Zero Head Space extraction (ZHE) procedure was developed. The reaction vessel comprised a filtration device with a nitrocellulose membrane. The separation was performed at 50 lb/in2 and 23 °C, with no headspace during the process. Water and methanol (both acidifie d) were evaluated as solvents during two extraction stages for the recovery and fractionation of polyphenols. Aqueous extract (AE) was mainly constituted by monomeric polyphenols while Methanol extract (ME) presented less soluble compounds, as well as a higher concentration of total anthocyanin content than AE. Additional methanolic (CE) and acetone (CAE) extractions of residual GP showed CE presented a similar profile to ME (at a lower concentration), indicating ZHE efficiency at extracting polyphenols in GP. CAE presented a non-resolved hump, characteristic of high proanthocyanidins’ polydispersity. ZHE rendered a monomeric fraction in ME (mean Degree of Polymerization, mDP of 1.38). Residual GP (cake) extractions demonstrated oligomeric polyphenol retention; mDP up to 3.05 when acetone was used. Fractionation of GP polyphenols was successfully established using a Zero Head space extractor.

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Arteel, Gavin E., and Helmut Sies. "Protection against peroxynitrite by cocoa polyphenol oligomers." FEBS Letters 462, no. 1-2 (November 22, 1999): 167–70. http://dx.doi.org/10.1016/s0014-5793(99)01498-2.

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Benbouguerra, Nawel, Josep Valls-Fonayet, Stephanie Krisa, François Garcia, Cédric Saucier, Tristan Richard, and Ruth Hornedo-Ortega. "Polyphenolic Characterization of Merlot, Tannat and Syrah Skin Extracts at Different Degrees of Maturity and Anti-Inflammatory Potential in RAW 264.7 Cells." Foods 10, no. 3 (March 5, 2021): 541. http://dx.doi.org/10.3390/foods10030541.

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(1) Background: Both sensory quality and healthy attributes of Vitis vinifera grapes used for winemaking are closely related with the polyphenolic composition of their skins. (2) Methods: In this study, the polyphenolic characterization (flavan-3-ols, procyanidins, flavonols, stilbenes, anthocyanins) was investigated by ultra performance liquid chromatography coupled to a triple quadrupole mass spectrometer (UPLC-QqQ-MS). Skins from Vitis vinifera Merlot, Tannat, and Syrah red grape varieties cultivated in the south of France at different stages of ripening in 2018 were used. The anti-inflammatory and the antioxidant potential of the extracts were evaluated by the measure of nitric oxide (NO) and the intracellular reactive oxygen species production (ROS) in lipopolysaccharide (LPS)-stimulated macrophages. (3) Results: 41 polyphenols were quantified in all samples. Generally, the flavan-3-ol and procyanidin content decreased during ripening whereas the anthocyanins and stilbenes increased. In addition, as a novelty of this work, a wide identification and characterization of monomeric and oligomeric stilbenes was assessed by using authentic standards isolated in our laboratory, some of them (parthenocissin A and miyabenol C) reported for the first time in Merlot, Tannat and Syrah cultivars. The before-veraison skin extracts of all studied varieties, exhibited higher NO and ROS productions inhibition (>50%) proving both antioxidant and anti-inflammatory properties.

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Kim, Hyun Woo, Soo Sung Kim, Kyo Bin Kang, Byeol Ryu, Eunjin Park, Jungmoo Huh, Won Kyung Jeon, et al. "Combined MS/MS-NMR Annotation Guided Discovery of Iris lactea var. chinensis Seed as a Source of Viral Neuraminidase Inhibitory Polyphenols." Molecules 25, no. 15 (July 26, 2020): 3383. http://dx.doi.org/10.3390/molecules25153383.

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In this study, the chemical diversity of polyphenols in Iris lactea var. chinensis seeds was identified by combined MS/MS-NMR analysis. Based on the annotated chemical profile, the isolation of stilbene oligomers was conducted, and consequently, stilbene oligomers (1-10) were characterized. Of these, compounds 1 and 2 are previously undescribed stilbene dimer glycoside (1) and tetramer glycoside (2), respectively. Besides, to evaluate this plant seed as a rich source of stilbene oligomers, we quantified three stilbene oligomers of I. lactea var. chinensis seeds. The contents of three major stilbene oligomers—trans-ε-viniferin (3), vitisin A (6), and vitisin B (9)—in I. lactea var. chinensis seeds were quantified as 2.32 (3), 4.95 (6), and 1.64 (9) mg/g dry weight (DW). All the isolated compounds were tested for their inhibitory activities against influenza neuraminidase. Compound 10 was found to be active with the half maximal inhibitory concentration (IC50) values at 4.76 μM. Taken together, it is concluded that I. lactea var. chinensis seed is a valuable source of stilbene oligomers with a human health benefit.

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Jacob, Jois Moriani, and Erda Eni Rame Hau. "INTERACTIONS OF OLIVE OIL POLYPHENOLS WITH AB OLIGOMERS." PARTNER 24, no. 2 (November 15, 2019): 1129. http://dx.doi.org/10.35726/jp.v24i2.387.

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Lachowicz, Sabina, and Jan Oszmiański. "Profile of Bioactive Compounds in the Morphological Parts of Wild Fallopia japonica (Houtt) and Fallopia sachalinensis (F. Schmidt) and Their Antioxidative Activity." Molecules 24, no. 7 (April 11, 2019): 1436. http://dx.doi.org/10.3390/molecules24071436.

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The aim of this study was to determine the content of triterpenoids and polyphenols, and antioxidative activity in leaves, stalks, and roots of plants from the species Fallopia as well as to present the main relationship between them. Polyphenolic compounds and triterpenoids were identified with liquid chromatography-photodiode detector-mass spectrometry/quadrupole time of flight (LC-MS-Q/TOF; qualitatively) and quantified with an ultra-performance liquid chromatography-photodiode detector (UPLC-PDA (quantitatively), and their antioxidative activity was determined with radical scavenging capacity (ABTS) and oxygen radical absorbance capacity (ORAC) assays. Generally, the wild Fallopia japonica Houtt. species had 1.2 times higher content of bioactive compounds and antioxidative activity than Fallopia sachalinensis. Contents of polyphenolic compounds determined in leaves, stalks, and roots were on average 17.81, 10.60, and 9.02 g/100 g of dry weight (DW), whereas the average contents of triterpenoids reached 0.78, 0.70, and 0.50 g/100 g DW, respectively. The leaves were a better source of polymeric procyanidins, phenolic acids, flavones, and flavonols, as well as oleanolic and ursolic acids than the other morphological parts of the tested plants. However, the roots were an excellent source of flavan-3-ols (monomeric and oligomer) and stilbenes, such as resveratrol, and their derivatives. The results obtained showed significant differences between plants of the wild Fallopia species and their morphological parts, and enabled selecting the most valuable morphological part of the tested plants to be used for food enrichment and nutraceuticals production. Therefore, the leaves seem to be the best as potential food additives for health, due to the above-average content of polyphenolic compounds and triterpenoids. In turn, roots, with their high contents of stilbenes and polyphenolic compounds, represent a good material for the medical, pharmaceutical, and cosmetic industries. The principal component analysis of the plants of wild Fallopia species and their morphological parts confirmed significant differences in their chemical composition.

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TANAKA, Takashi. "Oligomeric and Polymeric Plant Polyphenol." Kobunshi 46, no. 12 (1997): 893. http://dx.doi.org/10.1295/kobunshi.46.893.

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Matei, Petruta Mihaela, Laura Buzón-Durán, Eduardo Pérez-Lebeña, Jesús Martín-Gil, Beatrice Michaela Iacomi, M. Carmen Ramos-Sánchez, and Pablo Martín-Ramos. "In Vitro Antifungal Activity of Chitosan-Polyphenol Conjugates against Phytophthora cinnamomi." AgriEngineering 2, no. 1 (January 24, 2020): 72–77. http://dx.doi.org/10.3390/agriengineering2010005.

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Phytophthora cinnamomi is responsible for radical rot in a wide range of hosts, resulting in large economic and ecological losses worldwide. In Spain, it is responsible for diseases such as the oak decline or the chestnut blight. In this study, different polyphenol-stevioside inclusion compounds dispersed in a hydroalcoholic solution of chitosan oligomers have been investigated, with a view to their application as natural bioactive complexes to replace conventional systemic fungicides against this fungus. The polyphenols tested in vitro were curcumin, ferulic acid, gallic acid and silymarin. Three concentrations (125, 250 and 500 µg·mL−1) were assayed, with and without silver nanoparticles (AgNPs), and notable differences were found in the inhibition of mycelium growth, with EC50 and EC90 values ranging from 171 to 373.6 µg·mL−1, and from 446.2 to 963.7 µg·mL−1, respectively. The results obtained showed that the addition of AgNPs, despite their antimicrobial activity, did not always lead to synergies. In the case of P. cinnamomi, an unexpected antagonistic behavior was found for two of the polyphenols (curcumin and silymarin), while an additive behavior for ferulic acid and a synergistic behavior for gallic acid were attained. In view of their inhibitory power, the preparations based on ferulic acid with AgNPs and on silymarin without AgNPs are proposed for applications in crop and forests protection against P. cinnamomi.

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Corona, Giulia, Yang Ji, Prapaporn Anegboonlap, Sarah Hotchkiss, Chris Gill, Parveen Yaqoob, Jeremy P. E. Spencer, and Ian Rowland. "Gastrointestinal modifications and bioavailability of brown seaweed phlorotannins and effects on inflammatory markers." British Journal of Nutrition 115, no. 7 (February 16, 2016): 1240–53. http://dx.doi.org/10.1017/s0007114516000210.

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AbstractBrown seaweeds such asAscophyllum nodosumare a rich source of phlorotannins (oligomers and polymers of phloroglucinol units), a class of polyphenols that are unique to Phaeophyceae. At present, there is no information on the bioavailability of seaweed polyphenols and limited evidence on their bioactivityin vivo. Consequently, we investigated the gastrointestinal modificationsin vitroof seaweed phlorotannins fromA. nodosumand their bioavailability and effect on inflammatory markers in healthy participants.In vitro, some phlorotannin oligomers were identified after digestion and colonic fermentation. In addition, seven metabolites corresponding toin vitro-absorbed metabolites were identified. Urine and plasma samples contained a variety of metabolites attributed to both unconjugated and conjugated metabolites (glucuronides and/or sulphates). In both urine and plasma, the majority of the metabolites were found in samples collected at late time points (6–24 h), suggesting colonic metabolism of high-molecular-weight phlorotannins, with three phlorotannin oligomers (hydroxytrifuhalol A, 7-hydroxyeckol, C-O-C dimer of phloroglucinol) identified in urine samples. A significant increase of the cytokine IL-8 was also observed. Our study shows for the first time that seaweed phlorotannins are metabolised and absorbed, predominantly in the large intestine, and there is a large inter-individual variation in their metabolic profile. Three phlorotannin oligomers present in the capsule are excreted in urine. Our study is the first investigation of the metabolism and bioavailability of seaweed phlorotannins and the role of colonic biotransformation. In addition, IL-8 is a possible target for phlorotannin bioactivity.

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Matei, Petruta, Jesús Martín-Gil, Beatrice Michaela Iacomi, Eduardo Pérez-Lebeña, María Barrio-Arredondo, and Pablo Martín-Ramos. "Silver Nanoparticles and Polyphenol Inclusion Compounds Composites for Phytophthora cinnamomi Mycelial Growth Inhibition." Antibiotics 7, no. 3 (August 16, 2018): 76. http://dx.doi.org/10.3390/antibiotics7030076.

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Phytophthora cinnamomi, responsible for “root rot” or “dieback” plant disease, causes a significant amount of economic and environmental impact. In this work, the fungicide action of nanocomposites based on silver nanoparticles and polyphenol inclusion compounds, which feature enhanced bioavailability and water solubility, was assayed for the control of this soil-borne water mold. Inclusion compounds were prepared by an aqueous two-phase system separation method through extraction, either in an hydroalcoholic solution with chitosan oligomers (COS) or in a choline chloride:urea:glycerol deep eutectic solvent (DES). The new inclusion compounds were synthesized from stevioside and various polyphenols (gallic acid, silymarin, ferulic acid and curcumin), in a [6:1] ratio in the COS medium and in a [3:1] ratio in the DES medium, respectively. Their in vitro response against Phytophthora cinnamomi isolate MYC43 (at concentrations of 125, 250 and 500 µg·mL−1) was tested, which found a significant mycelial growth inhibition, particularly high for the composites prepared using DES. Therefore, these nanocomposites hold promise as an alternative to fosetyl-Al and metalaxyl conventional systemic fungicides.

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IINUMA, Munekazu, and Toshiyuki TANAKA. "Stilbene Oligomers as New Polyphenol-Their Structures and Bioactivities." Kagaku To Seibutsu 41, no. 4 (2003): 232–39. http://dx.doi.org/10.1271/kagakutoseibutsu1962.41.232.

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Radojčić Redovniković, I., K. Delonga, S. Mazor, V. Dragović-Uzelac, M. Carić, and J. Vorkapić-Furač. "Polyphenolic content and composition and antioxidative activity of different cocoa liquors." Czech Journal of Food Sciences 27, No. 5 (October 28, 2009): 330–37. http://dx.doi.org/10.17221/119/2008-cjfs.

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Cocoa liquor used in the confectionery industry comes from a wide range of geographical areas and may have different chemical compositions, sensory properties, and nutritional values. We found it interesting to study the polyphenolic content and composition of cocoa liquors for their potential use in industrial production. Six defatted samples originating from different countries were extracted with aqueous methanol (70%, v/v), and the polyphenolic profiles were determined using RP-HPLC method. According to our results, all samples of cocoa liquors have similar polyphenolic profiles, however, quantitatively varied. In the samples, about 13 compounds were identified by comparison of their retention times and UV spectra, and the quantified peaks were (+)-catechin, (–)-epicatechin, (–)-gallocatechin, (–)-epigallocatechin, caffeic acid derivative, caffeine, and theobromine. Also, several peaks were identified as oligomeric procyanidins. The free-radical scavenging activity was determined by the DPPH• (1,1'-dipheny-2-picrylhydrazyl) and Oxygen Radical Antioxidant Capacity (ORAC) assays. The order of antioxidant activity of the cocoa liquors studied was the same with both methods (Madagascar > Mexico > Ecuador > Venezuela > Sao Tome > Ghana samples). In addition, correlation between the antioxidant capacity and polyphenolic content was also determined, a high correlation coefficient having been obtained by both methods (<i>R<sup>2<Isup> = 0.9868 for DPPH, and 0.9375 for ORAC).

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Alberdi, Elena, María Victoria Sánchez-Gómez, Asier Ruiz, Fabio Cavaliere, Carolina Ortiz-Sanz, Tania Quintela-López, Estibaliz Capetillo-Zarate, Santiago Solé-Domènech, and Carlos Matute. "Mangiferin and Morin Attenuate Oxidative Stress, Mitochondrial Dysfunction, and Neurocytotoxicity, Induced by Amyloid Beta Oligomers." Oxidative Medicine and Cellular Longevity 2018 (June 14, 2018): 1–13. http://dx.doi.org/10.1155/2018/2856063.

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Amyloid beta- (Aβ-) mediated ROS overproduction disrupts intraneuronal redox balance and exacerbates mitochondrial dysfunction which leads to neuronal injury. Polyphenols have been investigated as therapeutic agents that promote neuroprotective effects in experimental models of brain injury and neurodegenerative diseases. The aim of this study was to identify the neuroprotective effects of morin and mangiferin against Aβ oligomers in cultured cortical neurons and organotypic slices as well as their mechanisms of action. Cell death caused by Aβ oligomers in neuronal cultures was decreased in the presence of micromolar concentrations of mangiferin or morin, which in turn attenuated oxidative stress. The neuroprotective effects of antioxidants against Aβ were associated with the reduction of Aβ-induced calcium load to mitochondria; mitochondrial membrane depolarization; and release of cytochrome c from mitochondria, a key trigger of apoptosis. Additionally, we observed that both polyphenols activated the endogenous enzymatic antioxidant system and restored oxidized protein levels. Finally, Aβ induced an impairment of energy homeostasis due to a decreased respiratory capacity that was mitigated by morin and mangiferin. Overall, the beneficial effects of polyphenols in preventing mitochondrial dysfunction and neuronal injury in AD cell models suggest that morin and mangiferin hold promise for the treatment of this neurological disorder.

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Das, Sukanya, Lina Stark, Ian F. Musgrave, Tara Pukala, and Scott D. Smid. "Bioactive polyphenol interactions with β amyloid: a comparison of binding modelling, effects on fibril and aggregate formation and neuroprotective capacity." Food & Function 7, no. 2 (2016): 1138–46. http://dx.doi.org/10.1039/c5fo01281c.

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Zheng, Qiuchen, Micheal T. Kebede, Merc M. Kemeh, Saadman Islam, Bethany Lee, Stuart D. Bleck, Liliana A. Wurfl, and Noel D. Lazo. "Inhibition of the Self-Assembly of Aβ and of Tau by Polyphenols: Mechanistic Studies." Molecules 24, no. 12 (June 22, 2019): 2316. http://dx.doi.org/10.3390/molecules24122316.

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The amyloid-β (Aβ) peptide and tau protein are thought to play key neuropathogenic roles in Alzheimer’s disease (AD). Both Aβ and tau self-assemble to form the two major pathological hallmarks of AD: amyloid plaques and neurofibrillary tangles, respectively. In this review, we show that naturally occurring polyphenols abundant in fruits, vegetables, red wine, and tea possess the ability to target pathways associated with the formation of assemblies of Aβ and tau. Polyphenols modulate the enzymatic processing of the amyloid-β precursor protein and inhibit toxic Aβ oligomerization by enhancing the clearance of Aβ42 monomer, modulating monomer–monomer interactions and remodeling oligomers to non-toxic forms. Additionally, polyphenols modulate tau hyperphosphorylation and inhibit tau β-sheet formation. The anti-Aβ-self-assembly and anti-tau-self-assembly effects of polyphenols increase their potential as preventive or therapeutic agents against AD, a complex disease that involves many pathological mechanisms.

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Williamson, Michael P., Clare Trevitt, and James M. Noble. "NMR studies of dextran oligomer interactions with model polyphenols." Carbohydrate Research 266, no. 2 (January 1995): 229–35. http://dx.doi.org/10.1016/0008-6215(94)00273-i.

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Reed, Jess D., Christian G. Krueger, and Martha M. Vestling. "MALDI-TOF mass spectrometry of oligomeric food polyphenols." Phytochemistry 66, no. 18 (September 2005): 2248–63. http://dx.doi.org/10.1016/j.phytochem.2005.05.015.

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Journal articles on the topic 'Polyphenolic oligomers'

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