Chemical Characterization, Free Radical Scavenging, and Cellular Antioxidant and Anti-Inflammatory Properties of a Stilbenoid-Rich Root Extract of Vitis vinifera

Metabolic Engineering of Corynebacterium glutamicum for the Production of Flavonoids and Stilbenoids

Flavonoids and stilbenoids, crucial secondary metabolites abundant in plants and fungi, display diverse biological and pharmaceutical activities, including potent antioxidant, anti-inflammatory, and antimicrobial effects. However, conventional production methods, such as chemical synthesis and plant extraction, face challenges in sustainability and yield. Hence, there is a notable shift towards biological production using microorganisms like Escherichia coli and yeast. Yet, the drawbacks of using E. coli and yeast as hosts for these compounds persist. For instance, yeast's complex glycosylation profile can lead to intricate protein production scenarios, including hyperglycosylation issues. Consequently, Corynebacterium glutamicum emerges as a promising alternative, given its adaptability and recent advances in metabolic engineering. Although extensively used in biotechnological applications, the potential production of flavonoid and stilbenoid in engineered C. glutamicum remains largely untapped compared to E. coli. This review explores the potential of metabolic engineering in C. glutamicum for biosynthesis, highlighting its versatility as a cell factory and assessing optimization strategies for these pathways. Additionally, various metabolic engineering methods, including genomic editing and biosensors, and cofactor regeneration are evaluated, with a focus on C. glutamicum. Through comprehensive discussion, the review offers insights into future perspectives in production, aiding researchers and industry professionals in the field.

Sustainable In Silico-Supported Ultrasonic-Assisted Extraction of Oligomeric Stilbenoids from Grapevine Roots Using Natural Deep Eutectic Solvents (NADES) and Stability Study of Potential Ready-to-Use Extracts

Grapevine roots, as a side-stream of a vineyard, are a sustainable resource for the recovery of oligomeric stilbenoids, such as the bioactive r-viniferin. The aim of this study is to evaluate an in silico-supported method, based on the Conductor-like Screening Model for Real Solvents (COSMO-RS), for selection of environmentally friendly natural deep eutectic solvents (NADES) with regard to the extraction of grapevine roots. The most suitable NADES system for ultrasonic-assisted extraction of r-viniferin was choline chloride/1,2-propanediol. The optimal extraction parameters for r-viniferin were determined using single-factor experiments as follows: choline chloride/1,2-propanediol 1/2 mol/mol, 10 wt% H2O, biomass/NADES ratio 1/10 g/g, and 10 min extraction time. Under optimized conditions, the extraction yield of r-viniferin from grapevine roots reached 76% of the total r-viniferin content. Regarding stability, stilbenoids in choline chloride/1,2-propanediol remained stable during 128 days of storage at ambient temperature. However, fructose/lactic acid-based NADES were observed to degrade stilbenoids; therefore, the removal of the NADES will be of interest, with a suitable method implemented using Amberlite® XAD-16N resin. As green solvents, the NADES have been used as effective and environmentally friendly extractants of stilbenoid-containing extracts from grapevine roots for potential applications in the cosmetic and pharmaceutical industry or as nutraceuticals in the food industry.

Exploring Phytochemical Composition and In Vivo Anti-Inflammatory Potential of Grape Seed Oil from an Alternative Source after Traditional Fermentation Processes: Implications for Phytotherapy

This study aimed to analyze the composition of grape seed oil (GSO) derived from an alternative source after traditional fermentation processes and its potential anti-inflammatory effects using an in vivo model of carrageenan-induced inflammation in mice. Gas chromatography high-resolution electron ionization mass spectrometry (GC-HR-EIMS) analysis identified eight main components in the GSO extract, including myristic acid methyl ester, palmitoleic acid methyl ester, methyl isoheptadecanoate, cis-linoleic acid, oleic acid methyl ester, linoleic acid stereoisomer, linoleic acid ethyl ester, and methyl (6E, 9E, 12E, 15E)-docose-6,9,12,15-tetraenoate. No significant differences were observed in the main fatty acids between commercially available grape seed oil and GSO extract obtained from fermented grape seeds. In the carrageenan-induced inflammation model, treatment with GSO resulted in a significant reduction in paw edema at 180 min, as in the reduction observed with diclofenac treatment. Combined treatment with GSO and diclofenac showed enhanced anti-inflammatory effects. Additionally, GSO exhibited antioxidative effects by decreasing the levels of glutathione (GSH) and malondialdehyde (MDA) in the serum. Chronic treatment with GSO for ten days did not provide a protective effect on inflammation. These findings suggest that GSO could be used as an alternative raw material and could possess anti-inflammatory and antioxidative properties. Further studies are needed to explore its potential therapeutic applications.

Chemistry, Biosynthesis and Pharmacology of Viniferin: Potential Resveratrol-Derived Molecules for New Drug Discovery, Development and Therapy

Viniferin is a resveratrol derivative. Resveratrol is the most prominent stilbenoid synthesized by plants as a defense mechanism in response to microbial attack, toxins, infections or UV radiation. Different forms of viniferin exist, including alpha-viniferin (α-viniferin), beta-viniferin (β-viniferin), delta-viniferin (δ-viniferin), epsilon-viniferin (ε-viniferin), gamma-viniferin (γ-viniferin), R-viniferin (vitisin A), and R2-viniferin (vitisin B). All of these forms exhibit a range of important biological activities and, therefore, have several possible applications in clinical research and future drug development. In this review, we present a comprehensive literature search on the chemistry and biosynthesis of and the diverse studies conducted on viniferin, especially with regards to its anti-inflammatory, antipsoriasis, antidiabetic, antiplasmodic, anticancer, anti-angiogenic, antioxidant, anti-melanogenic, neurodegenerative effects, antiviral, antimicrobial, antifungal, antidiarrhea, anti-obesity and anthelminthic activities. In addition to highlighting its important chemical and biological activities, coherent and environmentally acceptable methods for establishing vinferin on a large scale are highlighted to allow the development of further research that can help to exploit its properties and develop new phyto-pharmaceuticals. Overall, viniferin and its derivatives have the potential to be the most effective nutritional supplement and supplementary medication, especially as a therapeutic approach. More researchers will be aware of viniferin as a pharmaceutical drug as a consequence of this review, and they will be encouraged to investigate viniferin and its derivatives as pharmaceutical drugs to prevent future health catastrophes caused by a variety of serious illnesses.

Identifying Major Drivers of Antioxidant Activities in Complex Polyphenol Mixtures from Grape Canes

Grape canes represent a valuable source of numerous polyphenols with antioxidant properties, whose compositions vary depending on the genotype and environmental factors. Antioxidant activities of pure molecules are often reported without considering possible interactions that may occur in complex polyphenol mixture. Using UPLC-MS-based metabolomics and unsupervised classification, we explored the polyphenol variations in grape cane extracts from a collection of European varieties. Antioxidant activities were assessed using ORAC, ABTS, DPPH, FRAP, CUPRAC and chelation assays. Pairwise correlations between polyphenols and antioxidant capacities were performed to identify molecules that contributed more to the antioxidant capacities within a complex mixture of polyphenols.

Stilbenes: Source plants, chemistry, biosynthesis, pharmacology, application and problems related to their clinical Application-A comprehensive review

Stilbenes are some of the important phenolic compounds originating from plant families like Vitaceae, Leguminaceae, Gnetaceae, and Dipterocarpaceae. Structurally, they have a C6-C2-C6 skeleton, usually with two isomeric forms. Stilbenes are biosynthesized due to biotic and abiotic stresses such as microbial infections, high temperatures, and oxidation. This review aims to provide a comprehensive overview of stilbenes' botanical sources, chemistry, biosynthetic pathways, pharmacology, and clinical applications and challenges based on up-to-date data. All included studies were collected from PubMed, ScienceDirect, Google Scholar, and CNKI, and the presented data from these indexed studies were analyzed and summarized. A total of 459 natural stilbene compounds from 45 plant families and 196 plant species were identified. Pharmacological studies also show that stilbenes have various activities such as anticancer, antimicrobial, antioxidant, anti-inflammatory, anti-degenerative diseases, anti-diabetic, neuroprotective, anti-aging, and cardioprotective effects. Stilbene synthase (STS) is the key enzyme involved in stilbene biosynthetic pathways. Studies on the therapeutic application of stilbenes pinpoint that challenges such as low bioavailability and isomerization are the major bottlenecks for their development as therapeutic drugs. Although the medicinal uses of several stilbenes have been demonstrated in vivo and in vitro, studies on the development of stilbenes deserve more attention in the future.

Cell-Based Antioxidant Properties and Synergistic Effects of Natural Plant and Algal Extracts Pre and Post Intestinal Barrier Transport

In this work, both direct and indirect cell-based antioxidant profiles were established for 27 plant extracts and 1 algal extract. To evaluate the direct antioxidant effects, fluorescent AOP1 cell assay was utilized, which measures the ability of different samples to neutralize intracellular free radicals produced by a cell-based photo-induction process. As the intestinal barrier is the first cell line crossed by the product, dose response curves obtained from Caco-2 cells were used to establish EC50 values for 26 out of the 28 natural extracts. Among them, 11 extracts from Vitis, Hamamelis, Syzygium, Helichrysum, Ilex and Ribes genera showed remarkable EC50s in the range of 10 µg/mL. In addition to this, a synergistic effect was found when combinations of the most potent extracts (S. aromaticum, H. italicum, H. virginiana, V. vinifera) were utilized compared to extracts alone. Indirect antioxidant activities (i.e., the ability of cells to trigger antioxidant defenses) were studied using the ARE/Nrf2 luminescence reporter-gene assay in HepG2 cells, as liver is the first organ crossed by an edible ingredient once it enters in the bloodstream. Twelve extracts were subjected to an intestinal epithelial barrier passage in order to partially mimic intestinal absorption and show whether basolateral compartments could maintain direct or indirect antioxidant properties. Using postepithelial barrier samples and HepG2 cells as a target model, we demonstrate that indirect antioxidant activities are maintained for three extracts, S. aromaticum, H. virginiana and H. italicum. Our experimental work also confirms the synergistic effects of combinations of post-intestinal barrier compartments issued from apical treatment with these three extracts. By combining cell-based assays together with an intestinal absorption process, this study demonstrates the power of cell systems to address the issue of antioxidant effects in humans.

Abrogating Oxidative Stress as a Therapeutic Strategy against Parkinson’s Disease: A Mini Review of the Recent Advances on Natural Therapeutic Antioxidant and Neuroprotective Agents

Background:

Reactive oxygen species (ROS) play a vital role in cell signaling when maintained at low concentrations. However, when ROS production exceeds the neutralizing capacity of endogenous antioxidants, oxidative stress is observed, which has been shown to contribute to neurodegenerative diseases such as Parkinson's disease (PD). PD is a progressive disorder characterized by the loss of dopaminergic neurons from the striatum, which leads to motor and nonmotor symptoms. Although the complex interplay of mechanisms responsible are yet to be fully understood, oxidative stress was found to be positively associated with PD. Despite active research, currently proposed regimens mainly focus on regulating dopamine metabolism within the brain, even though these treatments have shown limited long-term efficacy and several side effects. Due to the implication of oxidative stress in the pathophysiology of PD, natural antioxidant compounds have attracted interest as potential therapeutics over the last years, with a more favorable anticipated safety profile due to their natural origin. Therefore, natural antioxidants are currently being explored as promising anti-PD agents.

Objective:

In this mini review, emphasis was given to presently studied natural antioxidant and neuroprotective agents that have shown positive results in PD animal models.

Methods:

For this purpose, recent scientific articles were reviewed and discussed, with the aim to highlight the most up-to-date advances on PD treatment strategies related to oxidative stress.

Results:

A plethora of natural compounds are actively being explored against PD, including kaemferol, icaritin, artemisinin, and α-bisabolol, with promising results. Most of these compounds have shown adequate neuroprotective ability along with redox balance restoration, normalized mitochondrial function and limitation of the oxidative damage.

Conclusion:

In conclusion, natural antioxidants may be the way forward to novel treatments against PD, when the limitations of correct dosing and appropriate combinations are resolved.

Plant Polyphenols for Aging Health: Implication from Their Autophagy Modulating Properties in Age-Associated Diseases

Polyphenols are a family of naturally occurring organic compounds, majorly present in fruits, vegetables, and cereals, characterised by multiple phenol units, including flavonoids, tannic acid, and ellagitannin. Some well-known polyphenols include resveratrol, quercetin, curcumin, epigallocatechin gallate, catechin, hesperetin, cyanidin, procyanidin, caffeic acid, and genistein. They can modulate different pathways inside the host, thereby inducing various health benefits. Autophagy is a conserved process that maintains cellular homeostasis by clearing the damaged cellular components and balancing cellular survival and overall health. Polyphenols could maintain autophagic equilibrium, thereby providing various health benefits in mediating neuroprotection and exhibiting anticancer and antidiabetic properties. They could limit brain damage by dismantling misfolded proteins and dysfunctional mitochondria, thereby activating autophagy and eliciting neuroprotection. An anticarcinogenic mechanism is stimulated by modulating canonical and non-canonical signalling pathways. Polyphenols could also decrease insulin resistance and inhibit loss of pancreatic islet β-cell mass and function from inducing antidiabetic activity. Polyphenols are usually included in the diet and may not cause significant side effects that could be effectively used to prevent and treat major diseases and ailments.

Synthesis and Biological Evaluation of 2,3,4-Triaryl-1,2,4-oxadiazol-5-ones as p38 MAPK Inhibitors

A series of azastilbene derivatives, characterized by the presence of the 1,2,4-oxadiazole-5-one system as a linker of the two aromatic rings of stilbenes, have been prepared as novel potential inhibitors of p38 MAPK. Biological assays indicated that some of the synthesized compounds are endowed with good inhibitory activity towards the kinase. Molecular modeling data support the biological results showing that the designed compounds possess a reasonable binding mode in the ATP binding pocket of p38α kinase with a good binding affinity.

Piceatannol Ameliorates Hepatic Oxidative Damage and Mitochondrial Dysfunction of Weaned Piglets Challenged with Diquat

Simple Summary

In our experiment, piglets in two challenged groups were orally administrated either piceatannol or another vehicle solution, and then injected with diquat, a bipyridyl herbicide that can cause a large amount of reactive oxygen species in animal bodies and is widely used to cause oxidative stress, to investigate the effects of piceatannol on hepatic redox status, mitochondrial function and the underlying mechanism. A control group was given neither piceatannol supplementation nor diquat injection. Results showed that piceatannol could improve hepatic redox status, preserve mitochondrial function, and prevent excessive apoptosis of liver cells. In addition, piceatannol might exert its protective effects through a classic antioxidant signaling pathway named Nrf2. Our findings indicated that piceatannol might be an appropriate candidate for further development as an antioxidant food supplement to minimize the risk of oxidative stress in young animals.

Abstract

The liver is an organ that produces large amounts of reactive oxygen species (ROS). Human infants or piglets are prone to oxidative damage due to their uncompleted development of the antioxidant system, causing liver disease. Piceatannol (PIC) has been found to have significant antioxidant effects. The aim of this experiment was to investigate the effects of PIC on the liver in piglets experiencing oxidative stress caused by diquat (DQ). After weaning, 54 male piglets (Duroc × [Landrace × Yorkshire]) were selected and randomly divided into three treatment groups: the CON group, the DQ-CON group, and the DQ-PIC group. The two challenged groups were injected with DQ and then orally administrated either PIC or another vehicle solution, while the control group was given sterile saline injections and an orally administrated vehicle solution. Compared to the results of the CON group, DQ increased the percentage of apoptosis cells in the liver, also decreased the amount of reduced glutathione (GSH) and increased the concentration of malondialdehyde (MDA). In addition, the adenosine triphosphate (ATP) production, activities of mitochondrial complex I, II, III, and V, and the protein expression level of sirtuin 1 (SIRT1) were inhibited by DQ. Furthermore, PIC supplementation inhibited the apoptosis of hepatic cells caused by DQ. PIC also decreased MDA levels and increased the amount of GSH. Piglets given PIC supplementation exhibited increased activities of mitochondrial complex I, II, III, and V, the protein expression level of SIRT1, and the ATP production in the liver. In conclusion, PIC affected the liver of piglets by improving redox status, preserving mitochondrial function, and preventing excessive apoptosis.

Research Advances in the Use of Bioactive Compounds from Vitis vinifera By-Products in Oral Care

Oral health is considered an important factor of general health and it contributes to the quality of life. Despite the raising awareness of preventive measures, the prevalence of oral health conditions continues to increase. In this context, a growing interest in investigating natural resources like Vitis vinifera (V. vinifera) phenolic compounds (PhCs) as oral health promoters has emerged. This paper aims to review the evidence about the bioactivities of V. vinifera by-products in oral health. Up to date, a high number of studies have thoroughly reported the antimicrobial and antiplaque activity of V. vinifera extracts against S. mutans or in multi-species biofilms. Moreover, the bioactive compounds from V. vinifera by-products have been shown to modulate the periodontal inflammatory response and the underlying oxidative stress imbalance induced by the pathogenic bacteria. Considering these beneficial effects, the utility of V. vinifera by-products in the maintaining of oral health and the necessary steps towards the development of oral care products were emphasized. In conclusion, the high potential of V. vinifera by-products could be valorized in the development of oral hygiene products with multi-target actions in the prevention and progression of several oral conditions.

A Reference List of Phenolic Compounds (Including Stilbenes) in Grapevine (Vitis vinifera L.) Roots, Woods, Canes, Stems, and Leaves

Due to their biological activities, both in plants and in humans, there is a great interest in finding natural sources of phenolic compounds or ways to artificially manipulate their levels. During the last decade, a significant amount of these compounds has been reported in the vegetative organs of the vine plant. In the roots, woods, canes, stems, and leaves, at least 183 phenolic compounds have been identified, including 78 stilbenes (23 monomers, 30 dimers, 8 trimers, 16 tetramers, and 1 hexamer), 15 hydroxycinnamic acids, 9 hydroxybenzoic acids, 17 flavan-3-ols (of which 9 are proanthocyanidins), 14 anthocyanins, 8 flavanones, 35 flavonols, 2 flavones, and 5 coumarins. There is great variability in the distribution of these chemicals along the vine plant, with leaves and stems/canes having flavonols (83.43% of total phenolic levels) and flavan-3-ols (61.63%) as their main compounds, respectively. In light of the pattern described from the same organs, quercetin-3-O-glucuronide, quercetin-3-O-galactoside, quercetin-3-O-glucoside, and caftaric acid are the main flavonols and hydroxycinnamic acids in the leaves; the most commonly represented flavan-3-ols and flavonols in the stems and canes are catechin, epicatechin, procyanidin B1, and quercetin-3-O-galactoside. The main stilbenes (trans-ε-viniferin, trans-resveratrol, isohopeaphenol/hopeaphenol, vitisin B, and ampelopsins) accumulate primarily in the woods, followed by the roots, the canes, and the stems, whereas the leaves, which are more exposed to environmental stresses, have a low concentration of these compounds. Data provided in this review could be used as (i) a metabolomic tool for screening in targeted and untargeted analyses and (ii) a reference list in studies aimed at finding ways to induce naturally occurring polyphenols on an industrial scale for pant and human disease control.

Neuroprotective Effects of Quercetin in Alzheimer's Disease

Quercetin is a flavonoid with notable pharmacological effects and promising therapeutic potential. It is widely distributed among plants and found commonly in daily diets predominantly in fruits and vegetables. Neuroprotection by quercetin has been reported in several in vitro studies. It has been shown to protect neurons from oxidative damage while reducing lipid peroxidation. In addition to its antioxidant properties, it inhibits the fibril formation of amyloid-β proteins, counteracting cell lyses and inflammatory cascade pathways. In this review, we provide a synopsis of the recent literature exploring the relationship between quercetin and cognitive performance in Alzheimer's disease and its potential as a lead compound in clinical applications.

Antioxidant Activity of Selected Stilbenoid Derivatives in a Cellular Model System

The stilbenoids, a group of naturally occurring phenolic compounds, are found in a variety of plants, including some berries that are used as food or for medicinal purposes. They are known to be beneficial for human health as anti-inflammatory, chemopreventive, and antioxidative agents. We have investigated a group of 19 stilbenoid substances in vitro using a cellular model of THP-1 macrophage-like cells and pyocyanin-induced oxidative stress to evaluate their antioxidant or pro-oxidant properties. Then we have determined any effects that they might have on the expression of the enzymes catalase, glutathione peroxidase, and heme oxygenase-1, and their effects on the activation of Nrf2. The experimental results showed that these stilbenoids could affect the formation of reactive oxygen species in a cellular model, producing either an antioxidative or pro-oxidative effect, depending on the structure pinostilbene (2) worked as a pro-oxidant and also decreased expression of catalase in the cell culture. Piceatannol (4) had shown reactive oxygen species (ROS) scavenging activity, whereas isorhapontigenin (18) had a mild direct antioxidant effect and activated Nrf2-antioxidant response element (ARE) system and elevated expression of Nrf2 and catalase. Their effects shown on cells in vitro warrant their further study in vivo.

Maximizing Polyphenol Content to Uncork the Relationship Between Wine and Cancer

Studies have revealed conflicting results regarding the risk of cancer from alcohol consumption. Furthermore, some studies have suggested that wine may have benefits that separate it from other alcoholic beverages. As wine contains a significant amount of chemicals, specifically polyphenols like anthocyanins and proanthocyanidins (PA), that can affect cellular function and promote health, this hypothesis is reasonably supported by recent research. Polyphenols promote several anticancer cellular pathways, including xenobiotic metabolism, support of innate antioxidant production, and stimulation of phase I and II detoxification of carcinogens. However, the multitude of growing and production conditions of grapes, including temperature, water availability, soil type, maceration, and aging can result in a remarkably varying final product based on the available literature. Thus, we hypothesize that wines produced from grapes cultivated between steady daily temperatures at 15–25°C with moderate sun exposure from flowering to harvest, lower vine-water status, resulting either from lower precipitation, and irrigation practices or more permeable soil types, limitation of fertilizers, extended maceration, and aging in oak will impact the concentration of anthocyanins and PA in the finished wine and may have a differential impact on cancer. This higher concentration of polyphenols would, in theory, create a healthier wine, thus explaining the conflicting reports on the benefits or harms of wine.

Strategic Syntheses of Vine and Wine Resveratrol Derivatives to Explore their Effects on Cell Functions and Dysfunctions

Trans-resveratrol, the most well-known polyphenolic stilbenoid, is found in grapes and accordingly in wine and it is considered to be beneficial for human health, especially towards the aging-linked cell alterations by providing numerous biological activities, such as anti-oxidant, antitumoral, antiviral, anti-inflammatory, neuroprotective, and platelet anti-aggregation properties. Although trans-resveratrol is a promising molecule, it cannot be considered as a drug, due to its weak bio-availability and fast metabolism. To overcome these weaknesses, several research teams have undertaken the synthesis of innovative trans-resveratrol derivatives, with the aim to increase its solubility in water and pharmacological activities towards cell targets. The aim of this review is to show the chronological evolution over the last 25 years of different strategies to develop more efficient trans-resveratrol derivatives towards organism physiology and, therefore, to enhance various pharmacological activities. While the literature on the development of new synthetic derivatives is impressive, this review will focus on selected strategies regarding the substitution of trans-resveratrol phenyl rings, first with hydroxy, methoxy, and halogen groups, and next with functionalized substituents. The effects on cell functions and dysfunctions of interesting resveratrol analogs will be addressed in this review.

Using the relative abundance of characteristic product ions in UHPLC-ESI-QTOF-MS2 methods to identify isomers of resveratrol oligomers in extracts of Xinjiang winegrape stems

Stilbenoids, particularly resveratrol and its oligomer, are abundantly present in grapes, and their antioxidant activities have been widely reported. A quick and simple method based on UHPLC-ESI-QTOF-MS² was established for the fragmentation pathways analysis of trans-ε-Viniferin, cis-ε-Viniferin, trans-δ-Viniferin and (-)-Hopeaphenol. MS/MS experiments on the [M-H]^- ions provided abundant structural information, especially regarding the relative abundance of the key product ion at m/z 347. The product ion was used to further identify structures in isomers of resveratrol dimers and its analogues. Based on the fragmentation pathways, we tentatively determined two compounds from the crude extracts of Xinjiang winegrape stems as Gnetin C and cis-Scirpusin A. Results from these experiments contribute to a more complete understanding of the stilbene compounds found in grape stems. The UHPLC-QTOF-MS² method can be used for the rapid analysis of stilbenes compounds in plant materials, foods and wine.

Oligostilbenoids in Vitis vinifera L. Pinot Noir grape cane extract: Isolation, characterization, in vitro antioxidant capacity and anti-proliferative effect on cancer cells

The following oligostilbenoids were isolated from extracts of Vitis vinifera L. Pinot Noir grape canes produced at a pilot-plant scale: (E)-ε-viniferin, (E)-resveratrol, (E)-piceatannol, ampelopsin A, vitisin B, pallidol, (E)-δ-viniferin, (E)-ω-viniferin, (E)-trans-cis-miyabenol C, isorhapontigenin, scirpusin A, and a new isomer named isoscirpusin A. The antioxidant capacity of the isolated stilbenoids was studied by three different assays, and their 50% inhibition concentration (IC₅₀) against cancer cells was determined by MTT reduction assay. Besides (E)-resveratrol, stilbenoids have outstanding antioxidant capacity in the ORAC-FL assay. The strongest antiproliferative effect was observed for (E)-piceatannol and ampelopsin A against the bladder cancer cell line J82. (E)-Piceatannol has inhibitory effect on human lung cancer SK-MES-1 cells. Moreover, the whole extract has antiproliferative effect on all tested cell lines. In conclusion, beside (E)-resveratrol, grape cane extract contains oligostilbenoids with potential health benefits. This underexploited viticultural residue has the potential to produce valuable phytochemicals or ingredients in functional foods.

Traditional and modern aspects of hemorrhoid treatment in Iran: a review

Hemorrhoidal disease is a prevalent anorectal condition which is generally not managed well with current pharmacologic interventions. However, in Iranian traditional medicine (ITM) there are numerous plants with hemorrhoid-healing properties. The present research assembled plants with hemorrhoid-healing properties in ITM; their related pharmacological effects, phytochemical constituents and mechanisms of action in the modern medicine were also gathered. For this purpose, leading ITM textbooks were searched for plants with hemorrhoid-healing effects. Further, in vitro, in vivo and clinical studies on the most cited species were considered using scientific databases. Studying ITM textbooks revealed 37 medicinal plants with hemorrhoid-healing effects. Among the mentioned herbal medicines, six species, including Allium ampeloprasum, Phyllanthus emblica, Aloe vera, Terminalia chebula, Vitis vinifera and Commiphora mukul, had the largest number of related pharmacological effects documented in scientific databases. These herbs from ITM should be considered as important resources for producing novel drugs for hemorrhoid treatment.

Gnetin-C and other resveratrol oligomers with cancer chemopreventive potential

Resveratrol has been extensively studied to investigate its biological effects, including its chemopreventive potential against cancer. Over the past decade, various resveratrol oligomers, both naturally occurring and synthetic, have been described. These resveratrol oligomers result from the polymerization of two or more resveratrol units to form dimers, trimers, tetramers, or even more complex derivatives. Some oligomers appear to have antitumor activities that are similar or superior to monomeric resveratrol. In this review, we discuss resveratrol oligomers with anticancer potential, with emphasis on well-characterized compounds, such as the dimer gnetin-C and other oligomers from Gnetum gnemon, whose safety, pharmacokinetic, and biological activities have been studied in humans.

Anti-Inflammatory Properties of Brazilian Green Propolis Encapsulated in a γ-Cyclodextrin Complex in Mice Fed a Western-Type Diet

Ageing is often accompanied by chronic inflammation. A fat- and sugar-rich Western-type diet (WTD) may accelerate the ageing phenotype. Cell culture studies have indicated that artepillin C-containing Brazilian green propolis exhibits anti-inflammatory properties. However, little is known regarding its anti-inflammatory potential in mouse liver in vivo. In this study, female C57BL/6NRj wild-type mice were fed a WTD, a WTD supplemented with Brazilian green propolis supercritical extract (GPSE) encapsulated in γ-cyclodextrin (γCD) or a WTD plus γCD for 10 weeks. GPSE-γCD did not affect the food intake, body weight or body composition of the mice. However, mRNA levels of the tumour necrosis factor α were significantly downregulated (p < 0.05) in these mice compared to those in the WTD-fed controls. Furthermore, the gene expression levels of other pro-inflammatory markers, including serum amyloid P, were significantly (p < 0.001) decreased following GPSE-γCD treatment. GPSE-γCD significantly induced hepatic ferritin gene expression (p < 0.01), which may contribute to its anti-inflammatory properties. Conversely, GPSE-γCD did not affect the biomarkers of endogenous antioxidant defence, including catalase, glutathione peroxidase-4, paraoxonase-1, glutamate cysteine ligase and nuclear factor erythroid 2-related factor-2 (Nrf2). Overall, the present data suggest that dietary GPSE-γCD exhibits anti-inflammatory, but not antioxidant activity in mouse liver in vivo. Thus, GPSE-γCD has the potential to serve as a natural hepatoprotective bioactive compound for dietary-mediated strategies against chronic inflammation.

Stilbenes from Vitis vinifera L. Waste: A Sustainable Tool for Controlling Plasmopara Viticola

Stilbene-enriched extracts from Vitis vinifera waste (cane, wood, and root) were characterized by UHPLC-MS. Eleven stilbenes were identified and quantified as follows: ampelopsin A, (E)-piceatannol, pallidol, (E)-resveratrol, hopeaphenol, isohopeaphenol, (E)-ε-viniferin, (E)-miyabenol C, (E)-ω-viniferin, r2-viniferin, and r-viniferin. The fungicide concentration inhibiting 50% of growth of Plasmopara viticola sporulation (IC₅₀) was determined for the extracts and also for the main compounds isolated. r-Viniferin followed by hopeaphenol and r2-viniferin showed low IC₅₀ and thus high efficacy against Plasmopara viticola. Regarding stilbene extracts, wood extract followed by root extract showed the highest antifungal activities. These data suggest that stilbene complex mixtures from Vitis vinifera waste could be used as a cheap source of bioactive stilbenes for the development of natural fungicides.