E-Mail Alert

Add your e-mail address to receive forthcoming issues of this journal:

Journal Browser

Journal Browser

Special Issue "Bioactive Phenolics and Polyphenols"

Quicklinks

A special issue of International Journal of Molecular Sciences (ISSN 1422-0067). This special issue belongs to the section "Bioactives and Nutraceuticals".

Deadline for manuscript submissions: closed (30 July 2014)

Special Issue Editors

Guest Editor
Prof. Dr. Antonio Segura-Carretero

Department of Analytical Chemistry of the University of Granada and CIDAF, Spain
Website | E-Mail
Interests: Bioactive phenolic compounds, metabolomics, analytical techniques, extraction processes, plant and food analysis, bioavailability
Guest Editor
Prof. Dr. David Arráez-Román

Department of Analytical Chemistry of the University of Granada and Research and Development Functional Food Centre (CIDAF), Spain
Website1 | Website2 | E-Mail
Phone: +34-958242869
Fax: +34-958243328
Interests: bioactive phenolic compounds; metabolomics; analytical techniques; extraction processes; plant and food analysis; bioavailability
Co-Guest Editor
Prof. Dr. Vladimír Křen

Institute of Microbiology, Academy of Sciences of the Czech Republic, Laboratory of Biotransformation, National Centre of Biocatalysis and Biotransformation, Videnska 1083, CZ 142 20 Praha 4, Czech Republic
Website | E-Mail
Fax: +420 296 442 509, 296 445 743
Interests: Biocatalysis and biotransformation; immobilized microbial cells, their use in production and biotransformation of natural products; biotransformation of natural products by enzymes and microorganisms; preparation of glycosidases of microbial origin and their use for glycosylation of natural compounds: glycoconjugates, multivalent compounds, ergot alkaloids, flavonoids, antioxidants and chemoprotectants

Special Issue Information

Dear Colleagues,

Phenolic compounds constitute one of the most widely distributed groups of substances in the plant kingdom. Nowadays, more than 10,000 different phenolic structures are currently known. In recent years, the study of phytochemicals from plants (compounds that possess beneficial effects on health) has been one of the main activities for developing functional foods, nutraceuticals, and pharmaceuticals. In this sense, the study of phenolic compounds has focused a lot of attention due to the scientific evidence derived from a large number of epidemiological studies which point to different biological activities attributed to these compounds. The most important effects of phenolic compounds include antioxidant, anti-inflammatory, hepatoprotective, antiviral, and antimicrobial activities. Notably, a high intake of fruits and vegetables that are rich in phenolic compounds has been related to a lower incidence of various illnesses, such as cardiovascular diseases, neurodegenerative pathologies, cancer, atherosclerosis, obesity, and diabetes. This Special Issue welcomes research articles discussing the use of “green” extraction process for extracting phenolic compounds from different matrices, their characterization by advanced separative techniques in plants, food, food sub-products, and biological samples, and the evaluation of their bioactivity and bioavailability using in vitro and in vivo models.

Prof. Dr. Antonio Segura-Carretero
Dr. David Arráez-Román
Prof. Vladimír Křen
Guest Editors

Submission

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. Papers will be published continuously (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are refereed through a peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. International Journal of Molecular Sciences is an international peer-reviewed Open Access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 1600 CHF.

Keywords

  • bioactive phenolic compounds
  • extraction process
  • separative techniques
  • bioactivity evaluation
  • bioavailability
  • food
  • plant
  • sub-products

Published Papers (23 papers)

View options order results:
result details:
Displaying articles 1-23
Export citation of selected articles as:

Research

Jump to: Review

Open AccessArticle A Two-Step Nanofiltration Process for the Production of Phenolic-Rich Fractions from Artichoke Aqueous Extracts
Int. J. Mol. Sci. 2015, 16(4), 8968-8987; doi:10.3390/ijms16048968
Received: 2 March 2015 / Revised: 11 April 2015 / Accepted: 16 April 2015 / Published: 22 April 2015
Cited by 3 | PDF Full-text (1575 KB) | HTML Full-text | XML Full-text
Abstract
Commercial nanofiltration (NF) membranes in spiral-wound configuration (NP030 from Microdyn Nadir and Desal DK from GE Water & Process Technologies) were used in a sequential design in order to produce a separated fraction of phenolic and sugar compounds from an aqueous artichoke extract.
[...] Read more.
Commercial nanofiltration (NF) membranes in spiral-wound configuration (NP030 from Microdyn Nadir and Desal DK from GE Water & Process Technologies) were used in a sequential design in order to produce a separated fraction of phenolic and sugar compounds from an aqueous artichoke extract. For both membranes, the effect of transmembrane pressure (TMP) on the permeation flux was evaluated. In optimized conditions of TMP, the NP030 membrane exhibited high rejections of apigenin, cynarin and chlorogenic acid (higher than 85%); on the other hand, very low rejections of fructose, glucose and sucrose (lower than 4%) were measured. Starting from an extract with a total antioxidant activity (TAA) of 5.28 mM trolox a retentate fraction with a TAA of 47.75 mM trolox was obtained. The NF permeate from the NP030 membrane was processed with the Desal DK membrane in optimized conditions of TMP producing a permeate stream free of phenolic and sugar compounds. Accordingly, as most part of phenolic compounds was removed in the first NF step, the concentration of sugar compounds in the NF retentate had much higher results than that of phenolic compounds. Full article
(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols)
Figures

Open AccessArticle Characterization of Flavonoid Glycosides from Fenugreek (Trigonella foenum-graecum) Crude Seeds by HPLC–DAD–ESI/MS Analysis
Int. J. Mol. Sci. 2014, 15(11), 20668-20685; doi:10.3390/ijms151120668
Received: 27 September 2014 / Revised: 28 October 2014 / Accepted: 3 November 2014 / Published: 11 November 2014
Cited by 5 | PDF Full-text (689 KB) | HTML Full-text | XML Full-text
Abstract
Fenugreek (Trigonella foenum-graecum) is a medicinal plant which is widely used for its pharmacological properties. In this study the phenolic composition of fenugreek crude seeds originating from Morocco has been investigated. Extraction was performed from defatted seeds by a hydromethanolic solution
[...] Read more.
Fenugreek (Trigonella foenum-graecum) is a medicinal plant which is widely used for its pharmacological properties. In this study the phenolic composition of fenugreek crude seeds originating from Morocco has been investigated. Extraction was performed from defatted seeds by a hydromethanolic solution using an Accelerated Solvent Extractor. HPLC technique coupled to negative ion electrospray ionization mass spectrometry and diode array detection was employed to identify the polyphenol in the obtained extract. The obtained results allowed the detection of 32 phenolic compounds among which various flavonoid glycosides and phenolic acids have been tentatively identified on the basis of their UV and MS spectra, and comparisons with standards when available, as well as with literature data. A systematic study of the obtained MS spectra and the observed fragmentation showed that most of the identified compounds were acylated and non-acylated flavonoids with apigenin, luteolin and kaempferol as aglycons. Hydroxycinnamic acids mostly dominated by caffeic acid derivatives were also detected. The quantitative analysis of the identified compounds showed that the phenolic composition of the studied crude fenugreek seeds was predominantly acylated and non-acylated flavone derivatives with apigenin as the main aglycon. Full article
(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols)
Figures

Open AccessArticle Rosmarinus Officinalis Leaves as a Natural Source of Bioactive Compounds
Int. J. Mol. Sci. 2014, 15(11), 20585-20606; doi:10.3390/ijms151120585
Received: 22 July 2014 / Revised: 23 October 2014 / Accepted: 31 October 2014 / Published: 10 November 2014
Cited by 16 | PDF Full-text (1159 KB) | HTML Full-text | XML Full-text
Abstract
In an extensive search for bioactive compounds from plant sources, the composition of different extracts of rosemary leaves collected from different geographical zones of Serbia was studied. The qualitative and quantitative characterization of 20 rosemary (Rosmarinus officinalis) samples, obtained by microwave-assisted
[...] Read more.
In an extensive search for bioactive compounds from plant sources, the composition of different extracts of rosemary leaves collected from different geographical zones of Serbia was studied. The qualitative and quantitative characterization of 20 rosemary (Rosmarinus officinalis) samples, obtained by microwave-assisted extraction (MAE), was determined by high performance liquid chromatography coupled to electrospray quadrupole-time of flight mass spectrometry (HPLC–ESI-QTOF-MS). The high mass accuracy and true isotopic pattern in both MS and MS/MS spectra provided by the QTOF-MS analyzer enabled the characterization of a wide range of phenolic compounds in the extracts, including flavonoids, phenolic diterpenes and abietan-type triterpenoids, among others. According to the data compiled, rosemary samples from Sokobanja presented the highest levels in flavonoids and other compounds such as carnosol, rosmaridiphenol, rosmadial, rosmarinic acid, and carnosic acid. On the other hand, higher contents in triterpenes were found in the extracts of rosemary from Gložan (Vojvodina). Full article
(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols)
Open AccessArticle Pine Bark and Green Tea Concentrated Extracts: Antioxidant Activity and Comprehensive Characterization of Bioactive Compounds by HPLC–ESI-QTOF-MS
Int. J. Mol. Sci. 2014, 15(11), 20382-20402; doi:10.3390/ijms151120382
Received: 28 July 2014 / Revised: 24 September 2014 / Accepted: 28 October 2014 / Published: 6 November 2014
Cited by 8 | PDF Full-text (1475 KB) | HTML Full-text | XML Full-text
Abstract
The consumption of polyphenols has frequently been associated with low incidence of degenerative diseases. Most of these natural antioxidants come from fruits, vegetables, spices, grains and herbs. For this reason, there has been increasing interest in identifying plant extract compounds. Polymeric tannins and
[...] Read more.
The consumption of polyphenols has frequently been associated with low incidence of degenerative diseases. Most of these natural antioxidants come from fruits, vegetables, spices, grains and herbs. For this reason, there has been increasing interest in identifying plant extract compounds. Polymeric tannins and monomeric flavonoids, such as catechin and epicatechin, in pine bark and green tea extracts could be responsible for the higher antioxidant activities of these extracts. The aim of the present study was to characterize the phenolic compounds in pine bark and green tea concentrated extracts using high-performance liquid chromatography coupled to electrospray ionization mass spectrometry (HPLC–ESI-QTOF-MS). A total of 37 and 35 compounds from pine bark and green tea extracts, respectively, were identified as belonging to various structural classes, mainly flavan-3-ol and its derivatives (including procyanidins). The antioxidant capacity of both extracts was evaluated by three complementary antioxidant activity methods: Trolox equivalent antioxidant capacity (TEAC), ferric reducing antioxidant power (FRAP) and oxygen radical absorbance capacity (ORAC). Higher antioxidant activity values by each method were obtained. In addition, total polyphenol and flavan-3-ol contents, which were determined by Folin–Ciocalteu and vanillin assays, respectively, exhibited higher amounts of gallic acid and (+)-catechin equivalents. Full article
(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols)
Open AccessArticle Mixed Pro- and Anti-Oxidative Effects of Pomegranate Polyphenols in Cultured Cells
Int. J. Mol. Sci. 2014, 15(11), 19458-19471; doi:10.3390/ijms151119458
Received: 30 July 2014 / Revised: 9 October 2014 / Accepted: 21 October 2014 / Published: 27 October 2014
Cited by 8 | PDF Full-text (761 KB) | HTML Full-text | XML Full-text
Abstract
In recent years, the number of scientific papers concerning pomegranate (Punica granatum L.) and its health properties has increased greatly, and there is great potential for the use of bioactive-rich pomegranate extracts as ingredients in functional foods and nutraceuticals. To translate this
[...] Read more.
In recent years, the number of scientific papers concerning pomegranate (Punica granatum L.) and its health properties has increased greatly, and there is great potential for the use of bioactive-rich pomegranate extracts as ingredients in functional foods and nutraceuticals. To translate this potential into effective strategies it is essential to further elucidate the mechanisms of the reported bioactivity. In this study HepG2 cells were supplemented with a pomegranate fruit extract or with the corresponding amount of pure punicalagin, and then subjected to an exogenous oxidative stress. Overall, upon the oxidative stress the gene expression and activity of the main antioxidant enzymes appeared reduced in supplemented cells, which were more prone to the detrimental effects than unsupplemented ones. No differences were detected between cells supplemented with the pomegranate juice or the pure punicalagin. Although further studies are needed due to the gaps existing between in vitro and in vivo studies, our results suggest caution in the administration of high concentrations of nutraceutical molecules, particularly when they are administered in concentrated form. Full article
(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols)
Figures

Open AccessArticle Caffeic Acid Reduces the Viability and Migration Rate of Oral Carcinoma Cells (SCC-25) Exposed to Low Concentrations of Ethanol
Int. J. Mol. Sci. 2014, 15(10), 18725-18741; doi:10.3390/ijms151018725
Received: 14 July 2014 / Revised: 9 October 2014 / Accepted: 10 October 2014 / Published: 17 October 2014
Cited by 3 | PDF Full-text (2328 KB) | HTML Full-text | XML Full-text
Abstract
Alcohol increases the risk of carcinoma originated from oral epithelium, but the biological effects of ultra-low doses of ethanol on existing carcinoma cells in combination with natural substances are still unclear. A role for ethanol (EtOH), taken in small amounts as an ingredient
[...] Read more.
Alcohol increases the risk of carcinoma originated from oral epithelium, but the biological effects of ultra-low doses of ethanol on existing carcinoma cells in combination with natural substances are still unclear. A role for ethanol (EtOH), taken in small amounts as an ingredient of some beverages or mouthwashes to change the growth behavior of established squamous cell carcinoma, has still not been examined sufficiently. We designed an in vitro study to determine the effect of caffeic acid (CFA) on viability and migration ability of malignant oral epithelial keratinocytes, exposed to ultra-low concentrations (maximum 100 mmol/L) EtOH. MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-dimethyltetrazolium bromide) and LDH (lactate dehydrogenase) assays were used to assess the cytotoxic effect of EtOH/CFA and the viability of squamous carcinoma SCC-25 cells (ATCC CRL-1628, mobile part of the tongue). Tested EtOH concentrations were: 2.5, 5, 10, 25, 50, and 100 mmol/L, along with an equal CFA concentration of 50 μmol/L. Carcinoma cells’ migration was investigated by monolayer “wound” healing assay. We demonstrated that very low concentrations of EtOH ranging between 2.5 and 10 mmol/L may induce the viability of oral squamous cell carcinoma cells, while the results following addition of CFA reveal an antagonistic effect, attenuating pro-proliferative EtOH activity. The migration rate of oral squamous carcinoma cells can be significantly inhibited by the biological activity of caffeic acid. Full article
(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols)
Open AccessArticle Effect of the Drying Process on the Intensification of Phenolic Compounds Recovery from Grape Pomace Using Accelerated Solvent Extraction
Int. J. Mol. Sci. 2014, 15(10), 18640-18658; doi:10.3390/ijms151018640
Received: 16 June 2014 / Revised: 6 September 2014 / Accepted: 9 September 2014 / Published: 15 October 2014
Cited by 5 | PDF Full-text (1210 KB) | HTML Full-text | XML Full-text
Abstract
In light of their environmental and economic interests, food byproducts have been increasingly exploited and valorized for their richness in dietary fibers and antioxidants. Phenolic compounds are antioxidant bioactive molecules highly present in grape byproducts. Herein, the accelerated solvent extraction (ASE) of phenolic
[...] Read more.
In light of their environmental and economic interests, food byproducts have been increasingly exploited and valorized for their richness in dietary fibers and antioxidants. Phenolic compounds are antioxidant bioactive molecules highly present in grape byproducts. Herein, the accelerated solvent extraction (ASE) of phenolic compounds from wet and dried grape pomace, at 45 °C, was conducted and the highest phenolic compounds yield (PCY) for wet (16.2 g GAE/100 g DM) and dry (7.28 g GAE/100 g DM) grape pomace extracts were obtained with 70% ethanol/water solvent at 140 °C. The PCY obtained from wet pomace was up to two times better compared to the dry byproduct and up to 15 times better compared to the same food matrices treated with conventional methods. With regard to Resveratrol, the corresponding dry pomace extract had a better free radical scavenging activity (49.12%) than the wet extract (39.8%). The drying pretreatment process seems to ameliorate the antiradical activity, especially when the extraction by ASE is performed at temperatures above 100 °C. HPLC-DAD analysis showed that the diversity of the flavonoid and the non-flavonoid compounds found in the extracts was seriously affected by the extraction temperature and the pretreatment of the raw material. This diversity seems to play a key role in the scavenging activity demonstrated by the extracts. Our results emphasize on ASE usage as a promising method for the preparation of highly concentrated and bioactive phenolic extracts that could be used in several industrial applications. Full article
(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols)
Figures

Open AccessArticle Reducing Capacity, Chlorogenic Acid Content and Biological Activity in a Collection of Scarlet (Solanum aethiopicum) and Gboma (S. macrocarpon) Eggplants
Int. J. Mol. Sci. 2014, 15(10), 17221-17241; doi:10.3390/ijms151017221
Received: 31 July 2014 / Revised: 11 September 2014 / Accepted: 17 September 2014 / Published: 26 September 2014
Cited by 9 | PDF Full-text (1198 KB) | HTML Full-text | XML Full-text
Abstract
Scarlet (Solanum aethiopicum) and gboma (S. macrocarpon) eggplants are important vegetables in Sub-Saharan Africa. Few studies have been made on these crops regarding the diversity of phenolic content and their biological activity. We have studied the reducing activity, the
[...] Read more.
Scarlet (Solanum aethiopicum) and gboma (S. macrocarpon) eggplants are important vegetables in Sub-Saharan Africa. Few studies have been made on these crops regarding the diversity of phenolic content and their biological activity. We have studied the reducing activity, the chlorogenic acid and other phenolic acid contents in a collection of 56 accessions of scarlet eggplant, including the four cultivated groups (Aculeatum, Gilo, Kumba, Shum) and the weedy intermediate S. aethiopicum-S. anguivi types, as well as in eight accessions of gboma eggplant, including the cultivated S. macrocarpon and its wild ancestor, S. dasyphyllum. A sample of the accessions evaluated in this collection has been tested for inhibition of nitric oxide (NO) using macrophage cell cultures. The results show that there is a great diversity in both crops for reducing activity, chlorogenic acid content and chlorogenic acid peak area (% of total phenolic acids). Heritability (H2) for these traits was intermediate to high in both crops. In all samples, chlorogenic acid was the major phenolic acid and accounted for more than 50% of the chromatogram peak area. Considerable differences were found among and within groups for these traits, but the greatest values for total phenolics and chlorogenic acid content were found in S. dasyphyllum. In most groups, reducing activity was positively correlated (with values of up to 0.904 in the Aculeatum group) with chlorogenic acid content. Inhibition of NO was greatest in samples having a high chlorogenic acid content. The results show that both crops are a relevant source of chlorogenic acid and other phenolic acids. The high diversity found also indicates that there are good prospects for breeding new scarlet and gboma eggplant cultivars with improved content in phenolics and bioactive properties. Full article
(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols)
Open AccessArticle Evaluation of the Antiradical Properties of Phenolic Acids
Int. J. Mol. Sci. 2014, 15(9), 16351-16380; doi:10.3390/ijms150916351
Received: 21 July 2014 / Revised: 5 September 2014 / Accepted: 9 September 2014 / Published: 16 September 2014
Cited by 6 | PDF Full-text (942 KB) | HTML Full-text | XML Full-text
Abstract
Antioxidant capacity (AOC) against peroxyl radical and 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS) radical cation was measured for a series of p-hydroxybenzoic (HB) and p-hydroxycinnamic (HC) acids at different pH. Quantum-chemical computation was performed using Gaussian 3.0 software package to calculate the
[...] Read more.
Antioxidant capacity (AOC) against peroxyl radical and 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS) radical cation was measured for a series of p-hydroxybenzoic (HB) and p-hydroxycinnamic (HC) acids at different pH. Quantum-chemical computation was performed using Gaussian 3.0 software package to calculate the geometry and energy parameters of the same compounds. Significant correlations were revealed between AOC and a number of calculated parameters. The most significant AOC descriptors for the studied compounds against peroxyl radical were found to be HOMO energy, rigidity (η) and Mulliken charge on the carbon atom in m-position to the phenolic hydroxyl. The most significant descriptor of the antioxidant properties against the ABTS radical cation at рН 7.40 is electron transfer enthalpy from the phenolate ion. The mechanism of AOC realization has been proposed for HB and HC acids against both radicals. Full article
(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols)
Open AccessArticle Recovering Bioactive Compounds from Olive Oil Filter Cake by Advanced Extraction Techniques
Int. J. Mol. Sci. 2014, 15(9), 16270-16283; doi:10.3390/ijms150916270
Received: 31 July 2014 / Revised: 4 September 2014 / Accepted: 5 September 2014 / Published: 15 September 2014
Cited by 5 | PDF Full-text (806 KB) | HTML Full-text | XML Full-text
Abstract
The potential of by-products generated during extra-virgin olive oil (EVOO) filtration as a natural source of phenolic compounds (with demonstrated bioactivity) has been evaluated using pressurized liquid extraction (PLE) and considering mixtures of two GRAS (generally recognized as safe) solvents (ethanol and water)
[...] Read more.
The potential of by-products generated during extra-virgin olive oil (EVOO) filtration as a natural source of phenolic compounds (with demonstrated bioactivity) has been evaluated using pressurized liquid extraction (PLE) and considering mixtures of two GRAS (generally recognized as safe) solvents (ethanol and water) at temperatures ranging from 40 to 175 °C. The extracts were characterized by high-performance liquid chromatography (HPLC) coupled to diode array detection (DAD) and electrospray time-of-flight mass spectrometry (HPLC-DAD-ESI-TOF/MS) to determine the phenolic-composition of the filter cake. The best isolation procedure to extract the phenolic fraction from the filter cake was accomplished using ethanol and water (50:50, v/v) at 120 °C. The main phenolic compounds identified in the samples were characterized as phenolic alcohols or derivatives (hydroxytyrosol and its oxidation product), secoiridoids (decarboxymethylated and hydroxylated forms of oleuropein and ligstroside aglycones), flavones (luteolin and apigenin) and elenolic acid derivatives. The PLE extraction process can be applied to produce enriched extracts with applications as bioactive food ingredients, as well as nutraceuticals. Full article
(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols)
Open AccessArticle Analysis of Phenolic Compounds and Antioxidant Abilities of Extracts from Germinating Vitis californica Seeds Submitted to Cold Stress Conditions and Recovery after the Stress
Int. J. Mol. Sci. 2014, 15(9), 16211-16225; doi:10.3390/ijms150916211
Received: 30 July 2014 / Revised: 25 August 2014 / Accepted: 5 September 2014 / Published: 12 September 2014
Cited by 3 | PDF Full-text (914 KB) | HTML Full-text | XML Full-text
Abstract
The material for this study consisted of stratified seeds of Vitis californica submitted to germination under optimum conditions (+25 °C) or under chill stress (+10 °C), also followed by recovery. It has been determined that the germinating seeds contain considerable amounts of tannins,
[...] Read more.
The material for this study consisted of stratified seeds of Vitis californica submitted to germination under optimum conditions (+25 °C) or under chill stress (+10 °C), also followed by recovery. It has been determined that the germinating seeds contain considerable amounts of tannins, catechins as well as phenolic acids such as gallic, p-coumaric, caffeic and ferulic acids. Gallic acid appeared in the highest amount in the germinating seeds (from 42.40–204.00 µg/g of fresh weight (FW)), followed by caffeic acid (from 6.62–20.13 µg/g FW), p-coumaric acid (from 2.59–5.41 µg/g FW), and ferulic acid (from 0.56–0.92 µg/g FW). The phenolic acids occurred mostly in the ester form. Under chill stress, the germinating seeds were determined to contain an elevated total amount of phenolics, as well as raised levels of condensed tannins, catechins, gallic acid, and gafeic acid. The levels of p-coumoric and ferulic acids were found to have decreased. In extracts isolated from a sample exposed to low temperature, increased antioxidant activity and reduction potential were also demonstrated. Tissue of the germinating seeds which underwent post-stress recovery was found to have less total phenolics. Full article
(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols)
Open AccessArticle TNF-α Blocker Effect of Naringenin-Loaded Sericin Microparticles that Are Potentially Useful in the Treatment of Psoriasis
Int. J. Mol. Sci. 2014, 15(8), 13624-13636; doi:10.3390/ijms150813624
Received: 19 May 2014 / Revised: 22 July 2014 / Accepted: 25 July 2014 / Published: 6 August 2014
Cited by 5 | PDF Full-text (2396 KB) | HTML Full-text | XML Full-text
Abstract
This study aims to evaluate the effect of combined use of the racemic flavanone Naringenin (NRG) and the protein sericin as TNF-α blockers. Sericin (SMs) and (R/S) NRG-loaded Sericin (SNRGMs) microparticles were prepared by spray-drying, characterized in terms of
[...] Read more.
This study aims to evaluate the effect of combined use of the racemic flavanone Naringenin (NRG) and the protein sericin as TNF-α blockers. Sericin (SMs) and (R/S) NRG-loaded Sericin (SNRGMs) microparticles were prepared by spray-drying, characterized in terms of morphology and particle size distribution, and encapsulation efficiency was determined. Concerning morphology and particle size distribution of microparticles, results indicated that they were not affected by the presence of NRG. The encapsulation efficiency was almost quantitative (93%), thus proving that sericin can be advantageously loaded with (R/S) NRG. Biological evaluation of (R/S) NRG, SMs and SNRGMs was then performed in lipopolysaccharide (LPS)-stimulated human peripheral blood mononuclear cells (hPBMC). SNRGMs resulted cytotoxic at the higher dose used (200 μg/mL) and the effect was greater than (R/S) NRG alone. Moreover, even if sericin alone was not effective in suppressing LPS-induced serum TNF-α levels, SNRGMs loaded with 9.3% of (R/S) NRG were significantly more potent than (R/S) NRG alone. In summary, this study provides the proof of concept that sericin-based microspheres loaded with TNF-α-blockers could contribute to the down regulation of the cytokine and represents the starting point for the development of new topical formulations for the treatment of middle-stage psoriasis. Full article
(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols)
Figures

Open AccessArticle Antioxidant Capacities and Total Phenolic Contents Enhancement with Acute Gamma Irradiation in Curcuma alismatifolia (Zingiberaceae) Leaves
Int. J. Mol. Sci. 2014, 15(7), 13077-13090; doi:10.3390/ijms150713077
Received: 28 May 2014 / Revised: 24 June 2014 / Accepted: 7 July 2014 / Published: 23 July 2014
Cited by 3 | PDF Full-text (909 KB) | HTML Full-text | XML Full-text
Abstract
The present study was conducted in order to assess the effect of various doses of acute gamma irradiation (0, 10, 15, and 20 Gy) on the improvement of bioactive compounds and their antioxidant properties of Curcuma alismatifolia var. Sweet pink. The high
[...] Read more.
The present study was conducted in order to assess the effect of various doses of acute gamma irradiation (0, 10, 15, and 20 Gy) on the improvement of bioactive compounds and their antioxidant properties of Curcuma alismatifolia var. Sweet pink. The high performance liquid chromatography (HPLC) and gas chromatography (GC) analysis uncovered that various types of phenolic, flavonoid compounds, and fatty acids gradually altered in response to radiation doses. On the other hand, antioxidant activities determined by 1,1-Diphenyl-2-picryl-hydrazyl (DPPH), ferric reduction, antioxidant power (FRAP), and 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging assay showed a higher irradiation level significantly increased the antioxidant properties. This study revealed an efficient effect of varying levels of gamma radiation, based on the pharmaceutical demand to enhance the accumulation and distribution of bioactive compounds such as phenolic and flavonoid compounds, fatty acids, as well as their antioxidant activities in the leaves of C. alismatifolia var. Sweet pink. Full article
(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols)
Open AccessArticle Nrf2-Mediated HO-1 Induction Coupled with the ERK Signaling Pathway Contributes to Indirect Antioxidant Capacity of Caffeic Acid Phenethyl Ester in HepG2 Cells
Int. J. Mol. Sci. 2014, 15(7), 12149-12165; doi:10.3390/ijms150712149
Received: 26 May 2014 / Revised: 17 June 2014 / Accepted: 25 June 2014 / Published: 9 July 2014
Cited by 19 | PDF Full-text (773 KB) | HTML Full-text | XML Full-text
Abstract
The objective of this study is to investigate the contributing effect of the nuclear transcription factor-erythroid 2-related factor 2 (Nrf2)-mediated signaling pathway on the indirect antioxidant capacity of caffeic acid phenethyl ester (CAPE) against oxidative stress in HepG2 cells. The result of an
[...] Read more.
The objective of this study is to investigate the contributing effect of the nuclear transcription factor-erythroid 2-related factor 2 (Nrf2)-mediated signaling pathway on the indirect antioxidant capacity of caffeic acid phenethyl ester (CAPE) against oxidative stress in HepG2 cells. The result of an antioxidant response element (ARE)-luciferase assay showed that CAPE stimulated ARE promoter activity resulting in increased transcriptional and translational activities of heme oxygenase-1 (HO-1). In addition, CAPE treatment enhanced Nrf2 accumulation in the nucleus and the post-translational phosphorylation level of extracellular signal-regulated kinase (ERK) among several protein kinases tested. Treatment with ERK inhibitor U126 completely suppressed CAPE-induced ERK phosphorylation and HO-1 expression, but it only partly inhibited CAPE-induced Nrf2 accumulation and ARE promoter. Using the 2',7'-dichlorofluorescein-diacetate (DCFH-DA) method, the cellular antioxidant capacity of CAPE against 2,2'-azobis (2-amidinopropane) dihydrochloride (AAPH)- or H2O2-induced oxidative stress also was shown to be partially suppressed by the ERK inhibitor. From the overall results it is proposed that the indirect antioxidant activity of CAPE against oxidative stress in HepG2 cells is partially attributed to induction of HO-1, which is regulated by Kelch-like erythroid-cell-derived protein with CNC homology (ECH)-associated protein 1 (Keap1)-independent Nrf2 activation relying on post-translational phosphorylation of ERK. Full article
(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols)
Open AccessArticle Proanthocyanidin Accumulation and Biosynthesis Are Modulated by the Irrigation Regime in Tempranillo Seeds
Int. J. Mol. Sci. 2014, 15(7), 11862-11877; doi:10.3390/ijms150711862
Received: 6 May 2014 / Revised: 3 June 2014 / Accepted: 16 June 2014 / Published: 4 July 2014
Cited by 1 | PDF Full-text (746 KB) | HTML Full-text | XML Full-text
Abstract
The main effects of three different irrigation regimes, i.e., sustained deficit irrigation (SDI), regulated deficit irrigation (RDI) and non-irrigated (NI), on seed traits namely proanthocyanidins (PAs) were evaluated in the wine grape cultivar Aragonez (syn. Tempranillo) grown in Alentejo (Portugal) over two
[...] Read more.
The main effects of three different irrigation regimes, i.e., sustained deficit irrigation (SDI), regulated deficit irrigation (RDI) and non-irrigated (NI), on seed traits namely proanthocyanidins (PAs) were evaluated in the wine grape cultivar Aragonez (syn. Tempranillo) grown in Alentejo (Portugal) over two growing seasons. Results showed that while the number of seeds per berry was not affected by water availability, seed fresh weight differed among treatments, the NI treatment exhibiting the lowest values. The biosynthetic pathway of flavanols appeared to be modified by the irrigation treatment, and several genes responsible for PA synthesis were up-regulated in the most stressed seeds (RDI and NI). However, this effect had no impact on PA content, suggesting the influence of other factors such as oxidation and/or degradation of PAs at late stages of maturation in grape seeds. The seeds’ non-enzymatic antioxidant capacities (oxygen radical absorbance capacity (ORAC) and hydroxyl radical adverting capacity (HORAC)) were modulated by water deficit and correlated well with PA content. The impact of irrigation strategy on PA biosynthesis, content, and anti-radical activity during seed ripening is discussed in the context of increasing interest in the role of PAs in the color and taste of wine, and the potential health benefits relating to their antioxidant capacity. Full article
(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols)
Open AccessCommunication Immunomodulating Activity of Aronia melanocarpa Polyphenols
Int. J. Mol. Sci. 2014, 15(7), 11626-11636; doi:10.3390/ijms150711626
Received: 19 May 2014 / Revised: 18 June 2014 / Accepted: 20 June 2014 / Published: 30 June 2014
Cited by 6 | PDF Full-text (529 KB) | HTML Full-text | XML Full-text
Abstract
The immunomodulating effects of isolated proanthocyanidin-rich fractions, procyanidins C1, B5 and B2 and anthocyanins of Aronia melanocarpa were investigated. In this work, the complement-modulating activities, the inhibitory activities on nitric oxide (NO) production in LPS-induced RAW 264.7 macrophages and effects on cell viability
[...] Read more.
The immunomodulating effects of isolated proanthocyanidin-rich fractions, procyanidins C1, B5 and B2 and anthocyanins of Aronia melanocarpa were investigated. In this work, the complement-modulating activities, the inhibitory activities on nitric oxide (NO) production in LPS-induced RAW 264.7 macrophages and effects on cell viability of these polyphenols were studied. Several of the proanthocyanidin-rich fractions, the procyanidins C1, B5 and B2 and the cyanidin aglycone possessed strong complement-fixing activities. Cyanidin 3-glucoside possessed stronger activity than the other anthocyanins. Procyanidins C1, B5 and B2 and proanthocyanidin-rich fractions having an average degree of polymerization (PD) of 7 and 34 showed inhibitory activities on NO production in LPS-stimulated RAW 264.7 mouse macrophages. All, except for the fraction containing proanthocyanidins with PD 34, showed inhibitory effects without affecting cell viability. This study suggests that polyphenolic compounds of A. melanocarpa may have beneficial effects as immunomodulators and anti-inflammatory agents. Full article
(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols)
Figures

Open AccessArticle Chrysin, Apigenin and Acacetin Inhibit Tumor Necrosis Factor-Related Apoptosis—Inducing Ligand Receptor-1 (TRAIL-R1) on Activated RAW264.7 Macrophages
Int. J. Mol. Sci. 2014, 15(7), 11510-11522; doi:10.3390/ijms150711510
Received: 14 April 2014 / Revised: 15 May 2014 / Accepted: 10 June 2014 / Published: 27 June 2014
Cited by 6 | PDF Full-text (1343 KB) | HTML Full-text | XML Full-text
Abstract
Expression level of Tumor Necrosis Factor—related apoptosis—inducing ligand (TRAIL) receptors is one of the most important factors of TRAIL-mediated apoptosis in cancer cells. We here report for the first time data concerning TRAIL-R1 and TRAIL-R2 receptor expression on RAW264.7 macrophages. Three substances belonging
[...] Read more.
Expression level of Tumor Necrosis Factor—related apoptosis—inducing ligand (TRAIL) receptors is one of the most important factors of TRAIL-mediated apoptosis in cancer cells. We here report for the first time data concerning TRAIL-R1 and TRAIL-R2 receptor expression on RAW264.7 macrophages. Three substances belonging to flavones: chrysin, apigenin and acacetin which differ from their substituents at the 4' position in the phenyl ring were used in assays because of the variety of biological activities (e.g., anticancer activity) of the polyphenol compounds. The expression of TRAIL-R1 and TRAIL-R2 death receptors on non-stimulated and LPS (lipopolysaccharide)-stimulated macrophages was determined using flow cytometry. We demonstrate that RAW264.7 macrophages exhibit TRAIL-R1 surface expression and that the tested compounds: chrysin, apigenin and acacetin can inhibit TRAIL-R1 death receptor expression level on macrophages. Full article
(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols)

Review

Jump to: Research

Open AccessReview A Review of Polyphenolics in Oak Woods
Int. J. Mol. Sci. 2015, 16(4), 6978-7014; doi:10.3390/ijms16046978
Received: 18 December 2014 / Revised: 12 February 2015 / Accepted: 13 February 2015 / Published: 27 March 2015
Cited by 6 | PDF Full-text (1192 KB) | HTML Full-text | XML Full-text
Abstract
Polyphenolics, which are ubiquitous in plants, currently are among the most studied phytochemicals because of their perceptible chemical properties and antioxidant activity. Oak barrels and their alternatives, which are widely used in winemaking nowadays, contribute polyphenolics to wines and are thought to play
[...] Read more.
Polyphenolics, which are ubiquitous in plants, currently are among the most studied phytochemicals because of their perceptible chemical properties and antioxidant activity. Oak barrels and their alternatives, which are widely used in winemaking nowadays, contribute polyphenolics to wines and are thought to play crucial roles in the development of wines during aging. This study summarizes the detailed information of polyphenolics in oak woods and their products by examining their structures and discussing their chemical reactions during wine aging. This paper evaluates the most recent developments in polyphenolic chemistry by summarizing their extraction, separation, and their identification by the use of chromatographic and spectral techniques. In addition, this paper also introduces polyphenol bioactive ingredients in other plant foods. Full article
(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols)
Open AccessReview Improved Release and Metabolism of Flavonoids by Steered Fermentation Processes: A Review
Int. J. Mol. Sci. 2014, 15(11), 19369-19388; doi:10.3390/ijms151119369
Received: 9 September 2014 / Revised: 16 October 2014 / Accepted: 20 October 2014 / Published: 24 October 2014
Cited by 11 | PDF Full-text (703 KB) | HTML Full-text | XML Full-text
Abstract
This paper provides an overview on steered fermentation processes to release phenolic compounds from plant-based matrices, as well as on their potential application to convert phenolic compounds into unique metabolites. The ability of fermentation to improve the yield and to change the profile
[...] Read more.
This paper provides an overview on steered fermentation processes to release phenolic compounds from plant-based matrices, as well as on their potential application to convert phenolic compounds into unique metabolites. The ability of fermentation to improve the yield and to change the profile of phenolic compounds is mainly due to the release of bound phenolic compounds, as a consequence of the degradation of the cell wall structure by microbial enzymes produced during fermentation. Moreover, the microbial metabolism of phenolic compounds results in a large array of new metabolites through different bioconversion pathways such as glycosylation, deglycosylation, ring cleavage, methylation, glucuronidation and sulfate conjugation, depending on the microbial strains and substrates used. A whole range of metabolites is produced, however metabolic pathways related to the formation and bioactivities, and often quantification of the metabolites are highly underinvestigated. This strategy could have potential to produce extracts with a high-added value from plant-based matrices. Full article
(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols)
Open AccessReview Culinary Herbs and Spices: Their Bioactive Properties, the Contribution of Polyphenols and the Challenges in Deducing Their True Health Benefits
Int. J. Mol. Sci. 2014, 15(10), 19183-19202; doi:10.3390/ijms151019183
Received: 14 July 2014 / Revised: 18 September 2014 / Accepted: 26 September 2014 / Published: 22 October 2014
Cited by 7 | PDF Full-text (708 KB) | HTML Full-text | XML Full-text
Abstract
Herbs and spices have been used for both culinary and medicinal purposes for centuries. Over the last decade, research into their role as contributors of dietary polyphenols, known to possess a number of properties associated with reducing the risk of developing chronic non-communicable
[...] Read more.
Herbs and spices have been used for both culinary and medicinal purposes for centuries. Over the last decade, research into their role as contributors of dietary polyphenols, known to possess a number of properties associated with reducing the risk of developing chronic non-communicable diseases, has increased. However, bearing in mind how these foods are consumed, normally in small quantities and in combination with other foods, it is unclear what their true benefit is from a health perspective. The aim of this review is to use the literature to discuss how preparative and digestive processes, bioavailability and interactions between foods may influence the bioactive properties of these foods, and whether or not polyphenols are responsible for these properties. Furthermore, this review aims to highlight the challenges that need to be addressed so as to determine the true benefits of these foods and the mechanisms of action that underpin their purported efficacy. Full article
(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols)
Open AccessReview Effects of the Olive-Derived Polyphenol Oleuropein on Human Health
Int. J. Mol. Sci. 2014, 15(10), 18508-18524; doi:10.3390/ijms151018508
Received: 28 July 2014 / Revised: 25 September 2014 / Accepted: 26 September 2014 / Published: 14 October 2014
Cited by 21 | PDF Full-text (956 KB) | HTML Full-text | XML Full-text
Abstract
The use of the products derived from the olive tree on human health dates back centuries. In several civilizations, the olive tree had and still has a very strong cultural and religious symbolism. Notably, the official seal and emblem of the World Health
[...] Read more.
The use of the products derived from the olive tree on human health dates back centuries. In several civilizations, the olive tree had and still has a very strong cultural and religious symbolism. Notably, the official seal and emblem of the World Health Organization features the rod of Asclepius over a world map surrounded by olive tree branches, chosen as a symbol of peace and health. Recently, accumulating experimental, clinical and epidemiological data have provided support to the traditional beliefs of the beneficial effect provided by olive derivates. In particular, the polyphenols present in olive leaves, olives, virgin (unrefined) olive oil and olive mill waste are potent antioxidant and radical scavengers with anti-tumor and anti-inflammatory properties. Here, we review the positive impact on human health of oleuropein, the most prevalent polyphenol present in olives. In addition, we provide data collected in our laboratory on the role of oleuropein in counteracting lipid accumulation in a mouse model of non-alcoholic fatty liver disease. Full article
(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols)
Figures

Open AccessReview Natural Bioactive Compounds from Winery By-Products as Health Promoters: A Review
Int. J. Mol. Sci. 2014, 15(9), 15638-15678; doi:10.3390/ijms150915638
Received: 30 June 2014 / Revised: 19 August 2014 / Accepted: 25 August 2014 / Published: 4 September 2014
Cited by 42 | PDF Full-text (865 KB) | HTML Full-text | XML Full-text
Abstract
The relevance of food composition for human health has increased consumers’ interest in the consumption of fruits and vegetables, as well as foods enriched in bioactive compounds and nutraceuticals. This fact has led to a growing attention of suppliers on reuse of agro-industrial
[...] Read more.
The relevance of food composition for human health has increased consumers’ interest in the consumption of fruits and vegetables, as well as foods enriched in bioactive compounds and nutraceuticals. This fact has led to a growing attention of suppliers on reuse of agro-industrial wastes rich in healthy plant ingredients. On this matter, grape has been pointed out as a rich source of bioactive compounds. Currently, up to 210 million tons of grapes (Vitis vinifera L.) are produced annually, being the 15% of the produced grapes addressed to the wine-making industry. This socio-economic activity generates a large amount of solid waste (up to 30%, w/w of the material used). Winery wastes include biodegradable solids namely stems, skins, and seeds. Bioactive compounds from winery by-products have disclosed interesting health promoting activities both in vitro and in vivo. This is a comprehensive review on the phytochemicals present in winery by-products, extraction techniques, industrial uses, and biological activities demonstrated by their bioactive compounds concerning potential for human health. Full article
(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols)
Figures

Open AccessReview Oleocanthal, a Phenolic Derived from Virgin Olive Oil: A Review of the Beneficial Effects on Inflammatory Disease
Int. J. Mol. Sci. 2014, 15(7), 12323-12334; doi:10.3390/ijms150712323
Received: 27 May 2014 / Revised: 25 June 2014 / Accepted: 26 June 2014 / Published: 11 July 2014
Cited by 20 | PDF Full-text (741 KB) | HTML Full-text | XML Full-text
Abstract
Virgin olive oil (VOO) is credited as being one of many healthful components of the Mediterranean diet. Mediterranean populations experience reduced incidence of chronic inflammatory disease states and VOO is readily consumed as part of an everyday dietary pattern. A phenolic compound contained
[...] Read more.
Virgin olive oil (VOO) is credited as being one of many healthful components of the Mediterranean diet. Mediterranean populations experience reduced incidence of chronic inflammatory disease states and VOO is readily consumed as part of an everyday dietary pattern. A phenolic compound contained in VOO, named oleocanthal, shares unique perceptual and anti-inflammatory characteristics with Ibuprofen. Over recent years oleocanthal has become a compound of interest in the search for naturally occurring compounds with pharmacological qualities. Subsequent to its discovery and identification, oleocanthal has been reported to exhibit various modes of action in reducing inflammatory related disease, including joint-degenerative disease, neuro-degenerative disease and specific cancers. Therefore, it is postulated that long term consumption of VOO containing oleocanthal may contribute to the health benefits associated with the Mediterranean dietary pattern. The following paper summarizes the current literature on oleocanthal, in terms of its sensory and pharmacological properties, and also discusses the beneficial, health promoting activities of oleocanthal, in the context of the molecular mechanisms within various models of disease. Full article
(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols)

Journal Contact

MDPI AG
IJMS Editorial Office
St. Alban-Anlage 66, 4052 Basel, Switzerland
ijms@mdpi.com
Tel. +41 61 683 77 34
Fax: +41 61 302 89 18
Editorial Board
Contact Details Submit to IJMS
Back to Top