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Defatted seed residues after the extraction of rose oil have their potential not fully described in the existing literature. The aim of this study was to determine and characterize the components important for the human body that are found in Rosa rugosa defatted seeds, including dietary fibers, proteins, selected minerals, polyphenols and antioxidant activity. Rosa rugosa seeds defatted with CO2 in supercritical conditions are a rich source of dietary fibers (approx. 65%) and proteins (15%); their macronutrients include the following: Ca (175.9), Mg (83.9), K (199.2) and Na (3.5 mg/100 g). They also contain polyphenols, including flavanols (0.9%) and total ellagic acid (0.5%), and they exhibit antioxidant activity (143.8 µM TAEC/g). Tellimagrandin I and II and rugosin A were found in the extracts, and ellagitannins with a yet-indeterminate structure were also present. The seeds also contained ellagitannin derivatives—galloyl-HHDP-glucose and bis-HHDP-glucose—at the same time, and they are characterized by a low-fat content—0.4%. The energy value of defatted rose seeds is about half the energy value of popular seeds used in the food industry. The findings of the present study suggest that defatted rosehip seeds, the by-product of rosehip processing, could be an important source of bioactive components like dietary fibers, flavanols, ellagitannins and mineral compounds. Therefore, defatted rose seeds are very promising and require further research, because they can potentially be used as a natural source of chemopreventive agents. [ABSTRACT FROM AUTHOR]

Non-structural protein 5 (Nsp5) is a cysteine protease that plays a key role in SARS-CoV-2 replication, suppressing host protein synthesis and promoting immune evasion. The investigation of natural products as a potential strategy for Nsp5 inhibition is gaining attention as a means of developing antiviral agents. In this work, we have investigated the physicochemical properties and structure-activity relationships of ellagic acid and its gut metabolites, urolithins A–D, as ligands of Nsp5. Results allow us to identify urolithin D as promising ligand of Nsp5, with a dissociation constant in the nanomolar range of potency. Although urolithin D is able to bind to the catalytic cleft of Nsp5, the appraisal of its viral replication inhibition against SARS-CoV-2 in Vero E6 assay highlights a lack of activity. While these results are discussed in the framework of the available literature reporting conflicting data on polyphenol antiviral activity, they provide new clues for natural products as potential viral protease inhibitors. [ABSTRACT FROM AUTHOR]

As the greatest defense organ of the body, the skin is exposed to endogenous and external stressors that produce reactive oxygen species (ROS). When the antioxidant system of the body fails to eliminate ROS, oxidative stress is initiated, which results in skin cellular senescence, inflammation, and cancer. Two main possible mechanisms underlie oxidative stress-induced skin cellular senescence, inflammation, and cancer. One mechanism is that ROS directly degrade biological macromolecules, including proteins, DNA, and lipids, that are essential for cell metabolism, survival, and genetics. Another one is that ROS mediate signaling pathways, such as MAPK, JAK/STAT, PI3K/AKT/mTOR, NF-κB, Nrf2, and SIRT1/FOXO, affecting cytokine release and enzyme expression. As natural antioxidants, plant polyphenols are safe and exhibit a therapeutic potential. We here discuss in detail the therapeutic potential of selected polyphenolic compounds and outline relevant molecular targets. Polyphenols selected here for study according to their structural classification include curcumin, catechins, resveratrol, quercetin, ellagic acid, and procyanidins. Finally, the latest delivery of plant polyphenols to the skin (taking curcumin as an example) and the current status of clinical research are summarized, providing a theoretical foundation for future clinical research and the generation of new pharmaceuticals and cosmetics. [ABSTRACT FROM AUTHOR]

• Ultrasonic assisted leaf extract of Basilicum polystachyon revealed the phenolic compounds present in the free, esterified and glycosylated forms. • First comparative RP-HPLC analysis of different phenolic forms in vivo and in vitro B. polystachyon leaf. • Gallic acid, trans -cinnamic acid, ellagic acid, quercetin and vanillic acid in B. polystachyon for the first time along with caffeic acid, p- coumaric acid and rosmarinic acid were identified. • B. polystachyon could serve as a souce of antioxidants. • Phenolic compounds of in vivo plants exhibited the higher antimicrobial activities against B. subtilis, S. aureus, M. smegmatis, E. coli and C. albicans. Basilicum polystachyon (L.) Moench is a member of Lamiaceae family and important ethnomedicinal that is widely used in the treatment of several ailments and is reputed to possess an inhibitor of the dengue virus. In vitro propagation is an efficient strategy for large-scale production of plantlets. Such process is a good alternative method for the production of valuable secondary metabolites. Hence, the present study assesses the contents of phenolic compounds, radical scavenging activity and antimicrobial efficacy of in vivo grown compared with the in vitro grown B. polystachyon plants. Thus, the antioxidant capacity of leaf extracts was determined by scavengers like ABTS .+ , DPPH. , hydrogen peroxide, hydroxyl radical, nitric oxide along with lipid peroxidation inhibition, FRAP, reducing power and DNA damage protection assay. The antimicrobial activity was evaluated through disk diffusion assay and minimum inhibitory concentration assay. RP-HPLC was used to identify and quantify the phenolic compounds in the following forms: free, esterified and glycosylated. The leaf extract of in vivo plants exhibited stronger antioxidant activities. The FRAP assay revealed a maximum reducing power with leaf extract of in vivo grown plants (43.73±0.52 µM Fe(II) equivalent). Total phenolic content of in vivo plants presented a strong positive correlation to IC 50 values of ABTS, DPPH, and HPSA, whereas total flavonoid content of in vitro grown plant was strongly correlated to IC 50 values of DPPH and HPSA. In vivo plants showed the highest inhibition zone against Bacillus subtilis, Escherichia coli , and Staphylococcus aureus. RP-HPLC analysis showed the phenolic compounds present in all tested forms of B. polystachyon leaf. For the first time, gallic acid, trans -cinnamic acid, ellagic acid, quercetin and vanillic acid were identified in this extract. Also, caffeic acid, p -coumaric acid and rosmarinic acid were quantified. These findings strongly suggest that B. polystachyon may be exploited as a promising natural source of antioxidants along with efficient antimicrobial agents. [ABSTRACT FROM AUTHOR]

Polyphenols, the secondary metabolites distributed in different parts of a plant, have major role in protecting the plants from deleterious effects of ultraviolet radiations and various diseases caused by pathogens. Considering the fact that these metabolites possess tremendous medicinal properties, extensive research has been carried out during the past few decades to explore their potential health benefits. Further, polyphenols are documented to possess different activities such as antioxidant, anticarcinogenic, anti-inflammatory, antimicrobial and antiulcer. The present study pertained to analyze different polyphenolic compounds in pollen grains of 9 medicinally important plant species viz., Bauhinia variegata, B.purpurea, Cassia biflora, C. fistula, C. glauca, C. saimea and Delonix regia belonging to Fabaceae family, Hibiscus rosa-sinensis belonging to Malvaceae family and Melia azadirach belonging toMeliaceaefamily using Ultra high-performance liquid chromatography (UHPLC). Various polyphenolic compounds likecaffeic acid, catechin, chlorogenic acid, coumaric acid, ellagic acid, epicatechin, gallic acid, kaempferol, quercetin, rutin, tert-butyl hydroquinone andumbelliferonewere found to be present in the pollen grains of these plant species. The order of plant species in terms of maximum number of polyphenolic compounds was observed as Cassia saimea (10) > B. purpurea (9) = C. fistula (9) = Hibiscus rosa-sinensis (9) > Delonix regia (8) > B. variegata (6) > C. glauca (4) = Melia Azadirach (4) > C. biflora (3). The plants such as C. saimea, B. purpurea, C. fistula and H. rosa-sinensis with different polyphenolic compounds indicated their potential for the treatment of ailments. [ABSTRACT FROM AUTHOR]

In this study, we carried out an exhaustive characterization of the polyphenol profile of strawberry, raspberry, blueberry, and blackberry decoctions; as well as the extractable (EPP) and hydrolysable (HPP) polyphenolic and proanthocyanidin profile of the residues obtained during berries decoctions (decoction by-products) by UPLC-ESI-Q-ToF MS. A greater variety of polyphenols was identified in the EPP fraction of the berry decoction by-products as compared to the decoctions, which were rich in several ellagitannins, flavonols, hydroxybenzoic acids, and anthocyanins. Ellagic acid was identified as the major polyphenol after acid hydrolysis in all berry decoction by-products, followed by hydroxybenzoic acid, which was found bound to the matrix by glycosidic, ether and ester bonds. Regarding proanthocyanidins, procyanidin, prodelphinidin, and propelargonidin dimers were identified in the strawberry, raspberry, and blackberry decoction by-products by MALDI-ToF MS. The results obtained from this study demonstrates that berries decoctions are rich in polyphenols; however, berry decoction by-products were richer in polyphenols with a great variety of extractable and non-extractable polyphenols. [ABSTRACT FROM AUTHOR]

Polyphenols are important active components in tea plants, which have strong biological activity and antioxidant activity. A certain degree of stress or exogenous substances can significantly increase the content of polyphenols in plants. γ-Aminobutyric acid (GABA), a natural functional amino acid, was used to study whether exogenous GABA can increase the content of polyphenols and enhance antioxidant activity in tea plants under heat-stress conditions. The results showed that the content of GABA was positively correlated with the content of polyphenols (r = 0.649), especially with the content of total catechins (r = 0.837). Most of the related genes encoding flavonoid metabolism (PAL, C4H, 4CL , CHS, CHI, F3H, F3′H, F3′5′H, DFR, LAR, ANS , ANR and FLS) as well as enzyme activities (PAL, C4H and 4CL) were upregulated. In addition, the activities of antioxidant enzymes were induced under heat-stress conditions. However, 3-mercaptopropionic acid (3-MPA), an inhibitor of GABA synthesis, exhibited opposite results under heat-stress conditions compared with GABA treatment. These results indicated that GABA plays a key role in the accumulation of polyphenols and the upregulation of the antioxidant system in tea plants under heat-stress conditions. • Exogenous GABA greatly contributed to catechin accumulation in tea. • Exogenous GABA actively induced increased POD, CAT and APX activities. • The catechin biosynthesis related genes were upregulated induced by GABA. [ABSTRACT FROM AUTHOR]

This study aimed to characterize the quality and bioactive compounds from five cultivars grown in Mexico´s northern region: Heritage, Summit, Harvest, and red and yellow Autumn. The physicochemical characteristics, DPPH anti-radical capacity, total phenolics, flavonoid and anthocyanins, polyphenolic profile, and ascorbic acid levels of the raspberries were assessed. The Harvest cultivar presented the highest weight and firmness and the lowest yield, total phenolics, and flavonoids. The yellow Autumn Bliss contained higher concentrations of polyphenols and ascorbic acid, and the red Autumn Bliss contained higher concentrations of flavonoids and anthocyanins and possessed a greater antioxidant capacity. The polyphenol profile indicated the presence of seven phenolic acids, namely, ellagic, gallic, caffeic, chlorogenic, p-coumaric, hydroxybenzoic, and protocatechuic acids; and four flavonoids, namely, catechin, quercetin-3-β-D-glucoside, quercetin-3-glucuronide, and rutin; these compounds were present in all the varieties, except for rutin, in yellow Autumn Bliss. The results of this study highlight the most valuable raspberry cultivars in terms of weight and firmness (Harvest), yield (Heritage), polyphenols and ascorbic acid (yellow Autumn Bliss), and anthocyanins and antioxidant capacity (red Autumn Bliss) in raspberries grown in northern Mexico. [ABSTRACT FROM AUTHOR]

[Display omitted] • Consensus docking is applied to evaluate binding of polyphenols to 3CLpro. • Ellagic acid is among strongest 3CLpro inhibitors of 19 polyphenols tested. • Ellagic acid binds into active site by hydrogen bonding and hydrophobic forces. • 3CLpro-polyphenols interactions are confirmed by surface plasmon resonance. The abundance of polyphenols in edible plants makes them an important component of human nutrition. Considering the ongoing COVID-19 pandemic, a number of studies have investigated polyphenols as bioactive constituents. We applied in-silico molecular docking as well as molecular dynamics supported by in-vitro assays to determine the inhibitory potential of various plant polyphenols against an important SARS-CoV-2 therapeutic target, the protease 3CLpro. Of the polyphenols in initial in-vitro screening, quercetin, ellagic acid, curcumin, epigallocatechin gallate and resveratrol showed IC 50 values of 11.8 µM to 23.4 µM. In-silico molecular dynamics simulations indicated stable interactions with the 3CLpro active site over 100 ns production runs. Moreover, surface plasmon resonance spectroscopy was used to measure the binding of polyphenols to 3CLpro in real time. Therefore, we provide evidence for inhibition of SARS-CoV-2 3CLpro by natural plant polyphenols, and suggest further research into the development of these novel 3CLpro inhibitors or biochemical probes. [ABSTRACT FROM AUTHOR]

Polyphenols are potent antioxidants, but their poor oral bioavailability owing to intrinsic insolubility and low permeability significantly hampers their effectiveness for clinical translation. Herein, upper intestinal absorptive polymer-lipid hybrid nanoparticles (PLN) was designed by exploiting the lipidic core for drug encapsulation and the decanoic acid conjugated rapeseed protein as the biopolymeric shell for gastrointestinal stability, retention and permeability. Polyphenol ellagic acid loaded core-shell PLN (EA-PLN(C/S)) was characterized of favorable physicochemical properties in simulated gastric- and intestinal fluids, including high drug loading capacity, slow drug release and prolonged stability. In Caco-2 monolayers, the cellular transport of EA-PLN(C/S) involved dual-paracellular and endocytosis pathways. Compared to drug in suspension or lipidic core nanoparticles, orally administered EA-PLN(C/S) was retained longer and more permeable via the duodenum and jejunum of upper intestine, resulting in up to 5.3-fold and 1.4-fold enhancement in the extent of drug absorption and colonic accumulation, respectively. In an acute colitis murine model, EA-PLN(C/S) at 6 mg/kg low dose markedly reduced colonic lipid peroxidation in contrast to no antioxidant effect in other EA formulations. This work suggests that integration of engineered plant protein biopolymer with lipid nanoparticles created unique oral drug delivery systems enabling intestinal site-specific absorption for effective antioxidant therapeutics. [Display omitted] [ABSTRACT FROM AUTHOR]

• Lentil protein isolate was conjugated with plant polyphenols. • Equilibrium binding constants decreased in the order quercetin > ellagic acid > rutin. • Random coil secondary structure of the proteins significantly increased upon conjugation. • Conjugates were less surface active than the original lentil proteins. • Radical scavenging and reducing power of the conjugates was better than the polyphenols. Lentil protein isolate (LPI) was conjugated with plant polyphenols (quercetin, rutin, ellagic acid), and the structural and functional characteristics of the conjugates were determined in comparison with the proteins and pure polyphenols. The interaction between polyphenols and protein was achieved by a grafting method at pH 9.0 in the presence of atmospheric oxygen. Surface plasmon resonance measurements showed polyphenols' direct interaction with LPI, with the order of binding strength quercetin > ellagic acid > rutin. The degree of conjugation also followed the same order. Structural analysis of the conjugates was performed using FTIR, intrinsic fluorescence, and surface hydrophobicity. A significant improvement in DPPḢ radical scavenging and ferric reducing antioxidant power of the conjugates was observed compared to the polyphenols. However, there was a decrease in the surface activity of the conjugates compared to LPI. Such conjugation provides a novel way to combine the advantages of using plant protein and polyphenols in developing a novel food ingredient. [ABSTRACT FROM AUTHOR]

The inhibition of α-glucosidase by nine galloyl-based polyphenols with free and unfree galloyl moieties (GMs) was studied. The results show that the inhibitory activity increased with the free GM number increasing. For the compounds with unfree GMs, ellagic acid and hexahydroxydiphenoyl group contributed to the enzyme inhibition. Free GMs could bind not only with the active site of α-glucosidase (competitive inhibition character), but also with the non-active sites (uncompetitive one); however, the former binding interaction was stronger than the latter one. All polyphenols that had inhibitory effects quenched α-glucosidase fluorescence in a static mode through forming a polyphenol-enzyme complex. The number of amino acid residues involved in polyphenol-enzyme binding interactions (hydrogen bonding and π-conjugations) increased with the inhibitory activity increasing. Additionally, two polyphenols with 5 free GMs showing certain hypoglycemic effects in maltose-loading test suggests that GM may be an advisable functional factor for alleviation of type II diabetes symptoms. [ABSTRACT FROM AUTHOR]

Abstract: Smaller, soluble oligomers of β-amyloid (Aβ) play a critical role in the pathogenesis of Alzheimer’s disease (AD). Selective inhibition of Aβ oligomer formation provides an optimum target for AD therapy. Some polyphenols have potent anti-amyloidogenic activities and protect against Aβ neurotoxicity. Here, we tested the effects of ellagic acid (EA), a polyphenolic compound, on Aβ42 aggregation and neurotoxicity in vitro. EA promoted Aβ fibril formation and significant oligomer loss, contrary to previous results that polyphenols inhibited Aβ aggregation. The results of transmission electron microscopy (TEM) and Western blot displayed more fibrils in Aβ42 samples co-incubated with EA in earlier phases of aggregation. Consistent with the hypothesis that plaque formation may represent a protective mechanism in which the body sequesters toxic Aβ aggregates to render them harmless, our MTT results showed that EA could significantly reduce Aβ42-induced neurotoxicity toward SH-SY5Y cells. Taken together, our results suggest that EA, an active ingredient in many fruits and nuts, may have therapeutic potential in AD. [Copyright &y& Elsevier]

• Forty-four hydrolyzable tannins were identified from Myrciaria jaboticaba peel. • Acid hydrolysis confirmed the presence of galloyl, HHDP and tergalloyl subunits. • Jabuticaba peel extract inhibited lipid oxidation in in vitro gastrointestinal digestion. • Cyanidin-3-Glc and hydrolyzable tannins contribute to the antioxidant capacity of the peel. Ultrasound-assisted and solvent extractions resulted in similar levels of hydrolyzable tannins (10.3–6.0 mg/g), anthocyanins (7.8–10.2 mg/g) and flavonols (0.24–0.32 mg/g) for dried Myrciaria jaboticaba peel (DJP). Ultrasound was efficient for the extraction of poorly soluble hydrolyzable tannins but affected the stability of anthocyanins and flavonols. UPLC-DAD-MS n allowed the identification of 44 hydrolyzable tannins as single and mixed hexosides bearing galloyl, HHDP and tergalloyl units. Twelve mixed HHDP-galloylgluconic acids and tergalloylated hexosides were newly discovered in this work. Acid hydrolysis of both ultrasonic extract and DJP yielded five major compounds, i.e. gallic acid, ellagic acid, gallic acid-C-hexoside, valoneic acid dilactone and sanguisorbic acid dilactone and pointed to higher contents in hydrolyzable tannins than by summing individual polyphenols after UPLC. Last, cyanidin-3- O -glucoside and hydrolyzable tannins from the ultrasonic extract inhibited lipid peroxidation of a Western type meal in in vitro digestion, suggesting a health benefit for these jabuticaba polyphenols. [ABSTRACT FROM AUTHOR]

The mode of interaction of polyphenolic compounds like genistein (GTN) and ellagic acid (EGA) with human and bovine serum albumin (HSA and BSA, respectively) was found to differ significantly. Stern-Volmer (SV) analysis of the fluorescence quenching data revealed that the binding strength of EGA (1.9 ± 0.09 × 105 M−1) to HSA is about one order of magnitude higher than GTN (2.24 ± 0.06 × 104 M−1). While the static quenching of HSA fluorescence was found to proceed through simple Stern-Volmer (SV) mechanism, a quenching sphere-of-action model was indispensable for BSA. Temperature dependent fluorescence along with a series of other biophysical experiments and ensemble docking calculation revealed that EGA and GTN bind to the serum proteins primarily through the entropy driven process. The α-helical content and the microenvironment near Trp residue of HSA and BSA did not show any appreciable change due to the binding of either GTN or EGA. Interestingly, both GTN and EGA were found to inhibit the formation of advanced glycated end (AGE) product of serum proteins up to the extent of 70–90% within 12–24 h. Relatively moderate binding propensity along with the anti-glycation ability of the polyphenols confirmed that GTN and EGA can be used either as an alternative or towards development of suitable drugs in the prevention of many diabetic-related complications. Suitable protein binding efficiency along with strong anti-glycation behaviour of polyphenolic compounds can lead to the development of suitable drugs to treat the diabetic-related complications. [Display omitted] • Genistein (GTN) and Ellagic acid (EGA) interact with HSA and BSA differently. • HSA and BSA fluorescence quenching follow linear and curved SV plots, respectively. • None of the drugs destroy the protein secondary structure and enzymatic activity. • Both the polyphenols inhibit the L-arabinose induced glycation of serum proteins. • These compounds can be re-purposed for the treatment of diabetic complications. [ABSTRACT FROM AUTHOR]

Polyphenols are natural organic compounds produced by plants, acting as antioxidants by reacting with ROS. These compounds are widely consumed in daily diet and many studies report several benefits to human health thanks to their bioavailability in humans. However, the digestion process of phenolic compounds is still not completely clear. Moreover, bioavailability is dependent on the metabolic phase of these compounds. The LogP value can be managed as a simplified measure of the lipophilicity of a substance ingested within the human body, which affects resultant absorption. The biopharmaceutical classification system (BCS), a method used to classify drugs intended for gastrointestinal absorption, correlates the solubility and permeability of the drug with both the rate and extent of oral absorption. BCS may be helpful to measure the bioactive constituents of foods, such as polyphenols, in order to understand their nutraceutical potential. There are many literature studies that focus on permeability, absorption, and bioavailability of polyphenols and their resultant metabolic byproducts, but there is still confusion about their respective LogP values and BCS classification. This review will provide an overview of the information regarding 10 dietarypolyphenols (ferulic acid, chlorogenic acid, rutin, quercetin, apigenin, cirsimaritin, daidzein, resveratrol, ellagic acid, and curcumin) and their association with the BCS classification. [ABSTRACT FROM AUTHOR]

Extracts from the defatted evening primrose (Oenothera paradoxa Hudziok) seeds are the source of a range of stable polyphenolic compounds, including ellagic acid, gallic acid, and catechin. Our studies evaluate, for the first time, the influence of evening primrose isopropanol extract (EPE) on malignant pleural mesothelioma (MPM) cells. MPM is rarely diagnosed, its high aggressiveness and frequently noted chemoresistance limit its treatment schemes and it is characterized by low prognostic features. Here, we demonstrate that EPE inhibited MPM growth in a dose-dependent manner in cells with increased invasion properties. Moreover, EPE treatment resulted in cell cycle arrest in the G2/M phase and increased apoptosis in invasive MPM cell lines. Additionally, EPE strongly limited invasion and MMP-7 secretion in MPM cancer cells. Our original data provide evidence about the potential anti-invasive effects of EPE in MPM therapy treatment. [ABSTRACT FROM AUTHOR]

• Effect of agricultural practice on raspberry phytochemical composition was studied. • Raspberry phytochemical composition depends on the cultivar and agricultural practice. • Polyphenols increased for the 'Kweli' cultivar under organic agricultural practice. • Polyphenols decreased for the 'Tulameen' cultivar under organic agricultural practice. Raspberries are rich in polyphenols but the impact of organic versus conventional agricultural practices on their phytochemical composition is not well known. This study aimed to analyse and compare the polyphenol accumulation in raspberries grown under both agricultural practices in the same edaphoclimatic conditions. Two raspberry cultivars 'Kweli' and 'Tulameen' were used. Under organic agricultural practices, the polyphenols levels increased for the 'Kweli' cultivar but decreased for the 'Tulameen' cultivar. 'Tulameen' cultivar grown under conventional agricultural practices contained higher anthocyanins levels than grown under organic agricultural practices while for the 'Kweli' cultivar no significant differences were observed between the two agricultural practices. 'Kweli' cultivar presented a significantly higher amount of ellagitannins and ellagic acid derivatives when compared to the 'Tulameen' cultivar under both agricultural practices. The effect of the agricultural practices on the raspberries' chemical profile was dependent on the cultivar and cannot be generalised. [ABSTRACT FROM AUTHOR]