How do in vitro digestion and cell metabolism affect the biological activity and phenolic profile of grape juice and wine.

Cabernet Sauvignon grape juice and wine underwent in vitro digestion, resulting in a reduction of most phenolic compounds (10%-100% decline), notably impacting anthocyanins (82%-100% decline) due to pH variations. However, specific phenolics, including p-hydroxybenzoic, protocatechuic, vanillic, p-coumaric, gallic and syringic acids, and coumarin esculetin, increased in concentration (10%-120%). Grape juice and wine samples showed comparable polyphenolic profile during all phases of digestion. Antioxidant activity persisted, and inhibition of angiotensin-I converting enzyme was improved after the digestion process, likely because of increased concentrations of listed phenolic acids and esculetin. Digested grape juice displayed comparable or superior bioactivity to red wine, indicating it as a promising source of accessible grape polyphenols for a broader audience. Nevertheless, Caco-2 cell model metabolization experiments revealed that only 3 of 42 analyzed compounds passed to the basolateral compartment, emphasizing the significant impact of digestion on polyphenol bioactivity, suggesting potential yet unmeasurable and overlooked implications for human health.

Comprehensive study of phenolic profile and biochemical activity of monovarietal red and white wines from Fruska Gora region, Serbia.

This paper presents a comprehensive study of commercially available monovarietal red and white wines from Fruska Gora mountain in Serbia, conducted to characterize their chemical and biochemical properties. Namely, 72 wines of 18 different Vitis vinifera varieties, including international, domestic and autochthonous ones, were assessed. Phenolic profile of wines was determined qualitatively, using spectrophotometric methods, and quantitatively, using LC-MS/MS and HPLC-UV/VIS methods. Quantified phenolic compounds pointed out differences between red and white wines, where some compounds stood out as distinctive characteristic of analyzed varieties, while others served as chemotaxonomic markers of the Fruska Gora region. Antioxidant and inhibitory properties towards acetylcholinesterase were evaluated for all wines and their relation to phenolic composition was investigated. This study is valuable since chemical and biochemical properties of domestic and autochthonous Fruska Gora varieties are reported for the first time. Also, international varieties studied herein gave distinctive information about the terroir of Fruska Gora region, which is scarce in scientific literature.

Beyond Mortality: Exploring the Influence of Plant Phenolics on Modulating Ferroptosis-A Systematic Review.

Ferroptosis is a recently discovered type of programmed cell death that is mechanistically different from other types of programmed cell death such as apoptosis, necroptosis, and autophagy. It is characterized by the accumulation of intracellular iron, overproduction of reactive oxygen species, depletion of glutathione, and extensive lipid peroxidation of lipids in the cell membrane. It was discovered that ferroptosis is interconnected with many diseases, such as neurodegenerative diseases, ischemia/reperfusion injury, cancer, and chronic kidney disease. Polyphenols, plant secondary metabolites known for many bioactivities, are being extensively researched in the context of their influence on ferroptosis which resulted in a great number of publications showing the need for a systematic review. In this review, an extensive literature search was performed. Databases (Scopus, Web of Science, PubMed, ScienceDirect, Springer) were searched in the time span from 2017 to November 2023, using the keyword "ferroptosis" alone and in combination with "flavonoid", "phenolic acid", "stilbene", "coumarin", "anthraquinone", and "chalcone"; after the selection of studies, we had 311 papers and 143 phenolic compounds. In total, 53 compounds showed the ability to induce ferroptosis, and 110 compounds were able to inhibit ferroptosis, and out of those compounds, 20 showed both abilities depending on the model system. The most researched compounds are shikonin, curcumin, quercetin, resveratrol, and baicalin. The most common modes of action are in the modulation of the Nrf2/GPX4 and Nrf2/HO-1 axis and the modulation of iron metabolism.

New Garden Rose (Rosa × hybrida) Genotypes with Intensely Colored Flowers as Rich Sources of Bioactive Compounds.

Garden roses, known as Rosa × hybrida, hold a prominent position as one of the most important and economically valuable plants in horticulture. Additionally, their products-essential oil, rose water, concrete, and concentrate-find extensive use in the cosmetic, pharmaceutical, and food industries, due to their specific fragrances and potential health benefits. Rose flowers are rich in biologically active compounds, such as phenolics, flavonoids, anthocyanins, and carotenoids. This study aims to investigate the potential of five new garden rose genotypes with intensely colored flowers to serve as sources of biologically active compounds. Phenolic profile was evaluated by determination of total phenolic (TPC), flavonoid (TFC), and monomeric anthocyanins (TAC) contents and LC-MS/MS analysis of selected compounds. Antioxidant activity was evaluated via DPPH and FRAP assays, neuroprotective potential via acethylcholinesterase inhibition assay, and antidiabetic activity viaα-amylase and α-glucosidase inhibition assays. The flowers of investigated genotypes were rich in phenolics (TPC varied from 148 to 260 mg galic acid eq/g de, TFC from 19.9 to 59.7 mg quercetin eq/g de, and TAC from 2.21 to 13.1 mg cyanidin 3-O-glucoside eq/g de). Four out of five genotypes had higher TPC than extract of R. damascene, the most famous rose cultivar. The dominant flavonoids in all investigated genotypes were glycosides of quercetin and kaempferol. The extracts showed high antioxidant activity comparable to synthetic antioxidant BHT, very high α-glucosidase inhibitory potential, moderate neuroprotective activity, and low potential to inhibit α-amylase.

Can Polyphenols Inhibit Ferroptosis?

Polyphenols, a diverse group of naturally occurring molecules commonly found in higher plants, have been heavily investigated over the last two decades due to their potent biological activities-among which the most important are their antioxidant, antimicrobial, anticancer, anti-inflammatory and neuroprotective activities. A common route of polyphenol intake in humans is through the diet. Since they are subjected to excessive metabolism in vivo it has been questioned whether their much-proven in vitro bioactivity could be translated to in vivo systems. Ferroptosis is a newly introduced, iron-dependent, regulated mode of oxidative cell death, characterized by increased lipid peroxidation and the accumulation of toxic lipid peroxides, which are considered to be toxic reactive oxygen species. There is a growing body of evidence that ferroptosis is involved in the development of almost all chronic diseases. Thus, ferroptosis is considered a new therapeutic target for offsetting many diseases, and researchers are putting great expectations on this field of research and medicine. The aim of this review is to critically analyse the potential of polyphenols to modulate ferroptosis and whether they can be considered promising compounds for the alleviation of chronic conditions.

Prenylated Acylphloroglucinols from Hypericum jovis with Anti-inflammatory Potential.

Thirteen prenylated acylphloroglucinols (1: -13: ), including 2 previously undescribed compounds (1: ) and (2: ), were isolated from Hypericum jovis. Their structures were elucidated by high-field NMR spectroscopy. The isolated prenylated acylphloroglucinols were evaluated for their anti-inflammatory effects in vitro through the reduction of the intercellular adhesion molecule 1 expression induced by TNF-α in the human microvascular endothelial cells 1 cell line. Compounds 3, 5, 6, 8,: and 12: significantly reduced intercellular adhesion molecule 1 expression in a concentration-dependent manner with IC50 values of 16.9, 34.4, 4.0, 3.2, and 7.7 µM, respectively. In addition, compound 12: showed notable inhibitory activity on the formation of cyclooxygenase-1- and 12-lipoxygenase-derived inflammatory mediators in an ex vivo cyclooxygenase-lipoxygenase assay. Eleven further constituents were isolated (14: -24: ), including the rare quercetin 3-O-(2-O-acetyl)-arabinofuranoside (18: ).

Role of Dietary Flavonoids in Iron Homeostasis.

Balancing systemic iron levels within narrow limits is critical for human health, as both iron deficiency and overload lead to serious disorders. There are no known physiologically controlled pathways to eliminate iron from the body and therefore iron homeostasis is maintained by modifying dietary iron absorption. Several dietary factors, such as flavonoids, are known to greatly affect iron absorption. Recent evidence suggests that flavonoids can affect iron status by regulating expression and activity of proteins involved the systemic regulation of iron metabolism and iron absorption. We provide an overview of the links between different dietary flavonoids and iron homeostasis together with the mechanism of flavonoids effect on iron metabolism. In addition, we also discuss the clinical relevance of state-of-the-art knowledge regarding therapeutic potential that flavonoids may have for conditions that are low in iron such as anaemia or iron overload diseases.

Activity profiling of Serbian and some other European Merlot wines in inflammation and oxidation processes.

Merlot are worldwide recognized red wines. Several studies show that red wines have health benefits, mainly due to their phenolic constituents. This study evaluates twelve Serbian and other five European (French, Italian, Macedonian, Slovenian, Spanish) Merlot wines in respect of their phenolic composition and biological activity. The latter was evaluated through a set of in vitro experiments related to common benefits of moderate red wine consumption in the prevention of cardiovascular diseases. Among the examined phenolics, the most abundant acid in all samples was the gallic acid (14.3-58.3 mg/L), catechin (9.1-49.3 mg/L) was the dominant flavonoid, malvidin-3-O-glucoside (2.63-66.5 mg/L) leading anthocyanin, whereas resveratrol was found in a usual concentration (0.18-4.67 mg/L). Differences determined in phenolic profiles, mainly in content of quercetin, rutin and p-coumaric acid, leaded to separation of Serbian from foreing Merlot wines. Results of standard antioxidant assays (DPPH•, ABTS•+ and •NO scavenger capacity reducing power (FRAP), lipid peroxidation) revealed French Merlot as the most potent, but also pointed out some Serbian samples. The correlation between the content of dominant phenolics and antioxidant activity was sporadic, but samples with the highest overall phenolic content, generally had higher antioxidant potential. Concentration of wines and number of cells in ant-inflammatory assay were chosen to mimic in vivo conditions. So, the potency of examined wines to decrease the production of macrophage-derived PGE2 and TXA2 (up to 65.5 and 47.9%, respectively), could be considered as in vitro evidence of positve health effect. Regarding the phenolic content and anti-inflammatory contribution of the most abundant compounds, no correlation was witnessed. In general, this study showed interesting potential of Serbian Merlot wines, comparable to health-promoting effects of renewed Eurepean ones.

Investigation of the chemical composition and biological activity of edible grapevine (Vitis vinifera L.) leaf varieties.

Chemical composition and bioactivity of eight edible Vitis vinifera L. leaf varieties originating from Fruska Gora, Serbia, including two autochthonous varieties, were evaluated. The LC-MS/MS analysis confirmed the presence of 28 natural products in leaf samples, among which most abundant were glycosylated flavonoids, ellagic and chlorogenic acids. The highest amounts of most of the tested compounds were detected in leaves of autochthonous variety Sila. Bioactivity was assessed by a set of in vitro antioxidant, neuroprotective and cytotoxic assays. Leaves of all examined varieties exhibited average bioactivity, with leaves of autochthonous variety Zupljanka standing out as the most promising sample. To conclude, investigated grapevine leaves proved to be a rich source of nutraceuticals, primarily antioxidants, and their further employment as medicinal food in human diet and beneficial raw material for food, pharmaceutical and cosmetic industries should be supported.

Quercetin inhibits intestinal non-haem iron absorption by regulating iron metabolism genes in the tissues.

PURPOSE: There is general agreement that some dietary polyphenols block non-haem iron uptake, but the mechanisms by which they achieve this action are poorly understood. Since the polyphenol quercetin is ingested daily in significant amounts, we have investigated the effect of quercetin on duodenal non-haem iron absorption in vivo, as well as its effect on factors known to be involved in systemic iron metabolism. METHODS: Rats were subject to gastric gavage and systemic quercetin administration. Treatments were followed with uptake studies using radiolabeled iron, serum iron and transferrin saturation measurements, LC-MS/MS analysis of quercetin metabolites in serum, determination of tissue non-haem iron content and analysis of gene expression of iron-related proteins. RESULTS: Both oral and intraperitoneal (IP) quercetin caused serum and tissue iron depletion by two means, first by increasing mucosal iron uptake and inhibiting iron efflux from duodenal mucosa, and second by decreasing levels of duodenal DMT1, Dcytb and FPN. Additionally, IP quercetin induced highly significant increased liver expression of hepcidin, a hormone known to inhibit intestinal iron uptake. CONCLUSIONS: Oral quercetin significantly inhibited iron absorption, while IP quercetin significantly affected iron-related genes. These results could lead to development of new effective ways of preventing and treating iron deficiency anaemia, the most widespread nutritional disorder in the world.

A colorimetric broth microdilution method for assessment of Helicobacter pylori sensitivity to antimicrobial agents.

Helicobacter pylori is a major infective etiological agent of the upper gastrointestinal tract diseases. The bacterium exhibits resistance to various conventional antibiotics, being usually challenging for eradication. Since there is an urge to consider alternative therapeutic strategies, the aim of the study was to examine selected essential oils of plants belonging to families Cupressaceae (Juniperus communis) and Lamiaceae (Hyssopus officinalis, Salvia officinalis, Melissa officinalis, Lavandula angustifolia, Ocimum basilicum and Thymus serpyllum) against H. pylori, using an improved microdilution broth method. The oils were examined in concentration range from 0.03 to 4 µL/mL. The method comprises Brain-heart infusion broth supplemented with yeast extract, horse serum and IsoVitaleX. After 3 day incubation, an equal volume of double strengthen Christensen's urea was added into each well and incubated for additional 4 h. In wells with present H. pylori, the medium changed color from yellow to purple, allowing MIC determination even without a microtitre plate reader. The microtitre format method is convenient as it is less expensive, easier to perform and requires less amount of an anti-H. pylori agent. The improved method enhances specificity to H. pylori, as fast urease activity is almost an exclusive property of this bacterium. The application of the second step incubation with Christensen's urea decreases the possibility of false positive/negative results due to contaminant growth or commonly poor H. pylori growth. Among the examined oils, J. communis, H. officinalis and O. basilicum were not active with the highest applied concentrations, while the most active was T. serpyllum, with MIC 2.0-4.0 µL/mL. This is the first report on essential oils activity of T. serpyllum and H. officinalis against H. pylori.

Phytochemical composition and in vitro functional properties of three wild rose hips and their traditional preserves.

The aim of the present study was investigation of the phenolic profile, ascorbic acid content, antioxidant, anti-acetylcholinesterase, anti-inflammatory and cytotoxic activity of rose hips and the preserves (purée and jam) of three insufficiently examined Rosa species: Rosa dumalis Bechst., R. dumetorum Thuill. and R. sempervirens L. The liquid chromatography-tandem mass spectrometry analysis resulted in quantification of 14 of the 45 phenolic compounds examined, with ellagic acid as the most dominant. Notable antioxidant activity of all three species was confirmed through several assays. Moderate inhibition of acetylcholinesterase by extracts of all investigated Rosa species was observed. Several extracts of examined Rosa species demonstrated inhibition potency towards production of some monitored eicosanoids in cyclooxygenase-1 and 12-lipoxygenase pathways. Two R. sempervirens extracts exerted cytotoxic activity against HeLa and HT-29 cell lines, but were inactive towards MRC-5 and MCF7. The results support the potential of these rose hips as food with health-promoting properties.

Binary mixture of Satureja hortensis and Origanum vulgare subsp. hirtum essential oils: in vivo therapeutic efficiency against Helicobacter pylori infection.

BACKGROUND: Helicobacter pylori can cause many gastrointestinal and also extra-gastrointestinal disorders and is a major risk factor for gastric carcinoma and MALT lymphoma. Currently, numerous antibiotic-based therapies are available; however, these therapies have numerous drawbacks, mainly due to increasing prevalence of antibiotic resistant strains. Thus, there is an urgent need to develop novel therapeutic agents against H. pylori infections. MATERIALS AND METHODS: In this study, the anti-H. pylori activity of 2:1 mixture of Satureja hortensis and Origanum vulgare subsp. hirtum essential oils (2MIX) was investigated in vivo. After screening in vitro cytotoxicity of 2MIX on mammalian cell lines, the therapeutic efficiency was studied in a mouse model, where changes in H. pylori colonization were detected by PCR and histology of gastric samples. The immune reaction of mice was tested based on cytokine and chemokine production, and the in vivo toxicity of 2MIX was also investigated by measuring ALT and AST enzyme activities and Cyp3a11 and HO-1 mRNA levels in livers of mice. RESULTS: 2MIX had not shown in vitro cytotoxicity against cell lines, only the highest concentration caused significant decrease in their survival rates. In the in vivo experiments, 2MIX successfully eradicated the pathogen in 70% of the mice. We could not detect toxicity or altered cytokine and chemokine balance after in vivo treatments in mice. CONCLUSIONS: These results show that 2MIX is effective in reducing H. pylori colonization suggesting that this essential oil mixture has great potential as a new, effective, and safe therapeutic agent against H. pylori.

Binary and Tertiary Mixtures of Satureja hortensis and Origanum vulgare Essential Oils as Potent Antimicrobial Agents Against Helicobacter pylori.

Essential oils possess strong antimicrobial activity, even against multiresistant Helicobacter pylori. Available therapies against H. pylori infection have multiple disadvantages, indicating a great need for a development of new therapeutics. The purpose of this study was to develop a potent natural product based anti-H. pylori formulation. First, anti-H. pylori activity of nine essential oils was determined, after which the most active oils were mixed in various ratios for further testing. Satureja hortensis, Origanum vulgare subsp. vulgare and O. vulgare subsp. hirtum essential oils expressed the highest activity (MIC = 2 µL mL(-1)). Their binary and ternary mixtures exhibited notably higher antimicrobial activity (MIC ≤ 2 µL mL(-1)). The most active was the mixture of S. hortensis and O. vulgare subsp. hirtum oils in volume ratio 2:1, which expressed 4 times higher activity than individual oils (MIC = 0.5 µL mL(-1)). According to GC-MS, both oils in the mixture were characterized by high content of phenols (48-73%), with carvacrol as the main carrier of antimicrobial activity. Presented in vitro study pointed out binary mixture of S. hortensis and O. vulgare subsp. hirtum essential oils in volume ratio 2:1 as promising candidate for further in vivo studies targeting H. pylori infection.

Comparative study of biological activities and phytochemical composition of two rose hips and their preserves: Rosa canina L. and Rosa arvensis Huds.

The aim of this study was to compare phenolic profile, vitamin C content, antioxidant, anti-inflammatory and cytotoxic activity of rose hips and the preserves (purée and jam) of two Rosa species: renowned Rosa canina L. and unexplored Rosa arvensis Huds. The liquid chromatography-tandem mass spectrometry analysis of 45 phenolics resulted in quantification of 14 compounds, with quercitrin, gallic and protocatechuic acids as the most dominant. High antioxidant potential of R. canina and a moderate activity of R. arvensis extracts were determined through several assays. Purée of both species and methanol extract of air-dried R. canina hips showed some anti-inflammatory (cyclooxygenase-1 and 12-lipooxygense inhibition potency) activity. Purée of R. canina exerted cytotoxic activity only against the HeLa cell line among several others (HeLa, MCF7, HT-29 and MRC-5). The presented results support traditional use of rose hips and their fruit preserves as food with health and nutritional benefits.

Quercetin inhibits intestinal iron absorption and ferroportin transporter expression in vivo and in vitro.

Balancing systemic iron levels within narrow limits is critical for maintaining human health. There are no known pathways to eliminate excess iron from the body and therefore iron homeostasis is maintained by modifying dietary absorption so that it matches daily obligatory losses. Several dietary factors can modify iron absorption. Polyphenols are plentiful in human diet and many compounds, including quercetin--the most abundant dietary polyphenol--are potent iron chelators. The aim of this study was to investigate the acute and longer-term effects of quercetin on intestinal iron metabolism. Acute exposure of rat duodenal mucosa to quercetin increased apical iron uptake but decreased subsequent basolateral iron efflux into the circulation. Quercetin binds iron between its 3-hydroxyl and 4-carbonyl groups and methylation of the 3-hydroxyl group negated both the increase in apical uptake and the inhibition of basolateral iron release, suggesting that the acute effects of quercetin on iron transport were due to iron chelation. In longer-term studies, rats were administered quercetin by a single gavage and iron transporter expression measured 18 h later. Duodenal FPN expression was decreased in quercetin-treated rats. This effect was recapitulated in Caco-2 cells exposed to quercetin for 18 h. Reporter assays in Caco-2 cells indicated that repression of FPN by quercetin was not a transcriptional event but might be mediated by miRNA interaction with the FPN 3'UTR. Our study highlights a novel mechanism for the regulation of iron bioavailability by dietary polyphenols. Potentially, diets rich in polyphenols might be beneficial for patients groups at risk of iron loading by limiting the rate of intestinal iron absorption.

Phenolic profile, antioxidant, anti-inflammatory and cytotoxic activities of black (Tuber aestivum Vittad.) and white (Tuber magnatum Pico) truffles.

The aim of this study was a comprehensive investigation on phenolic profile, antioxidant, anti-inflammatory and cytotoxic activity of the still insufficiently explored black summer truffles (Tuber aestivum Vittad.) and white (Tuber magnatum Pico) truffles. Methanol and water extracts, obtained by maceration and Soxhlet extraction, were examined. Forty-five phenolics was studied using LC-MS/MS: presence of 14 compounds was confirmed, with the most dominant being p-hydroxybenzoic acid, baicalein and kaempferol (T. aestivum), epicatechin and catechin (T. magnatum). Moderate antioxidant activity of both species was determined through several assays. Only T. magnatum showed anti-inflammatory potential by inhibiting COX-1 and 12-LOX pathway products synthesis. Methanol extracts exerted cytotoxicity against some tumour cell lines (HeLa, MCF7, HT-29), besides the prominent activity of water extracts towards breast adenocarcinoma (MCF7). To conclude, these results support further investigations of phytochemicals and biological activity towards verification of nutraceutical use of both species.

Quantitative determination of plant phenolics in Urtica dioica extracts by high-performance liquid chromatography coupled with tandem mass spectrometric detection.

A method for quantification of 45 plant phenolics (including benzoic acids, cinnamic acids, flavonoid aglycones, C- and O-glycosides, coumarins, and lignans) in plant extracts was developed, based on reversed phase HPLC separation of extract components, followed by tandem mass spectrometric detection. The phenolic profile of 80% MeOH extracts of the stinging nettle (Urtica dioica L.) herb, root, stem, leaf and inflorescence was obtained by using this method. Twenty-one of the investigated compounds were present at levels above the reliable quantification limit, with 5-O-caffeoylquinic acid, rutin and isoquercitrin as the most abundant. The inflorescence extracts were by far the richest in phenolics, with the investigated compounds amounting 2.5-5.1% by weight. As opposed to this, the root extracts were poor in phenolics, with only several acids and derivatives being present in significant amounts. The results obtained by the developed method represent the most detailed U. dioica chemical profile so far.

Liquid chromatography/tandem mass spectrometry study of anti-inflammatory activity of plantain (Plantago L.) species.

To evaluate anti-inflammatory activity of selected Plantago species (P. lanceolata L. and P. major L.) an optimized in vitro test for determination of cyclooxygenase-1 (COX-1) and 12-lipoxygenase (12-LOX) inhibition potency was undertaken. By using intact cell system (platelets) as a source of COX-1 and 12-LOX enzymes and highly sensitive and specific LC-MS/MS technique for detection of main arachidonic acid metabolites formed by COX-1 and 12-LOX, this test provides efficient method for evaluation of anti-inflammatory potential of plant extracts and isolated compounds. Our results validated the well-known COX-1 inhibitory activity of P. lanceolata and P. major methanol extracts (concentration required for 50% inhibition (IC(50)) was 2.00 and 0.65 mg/ml, respectively). Furthermore, 12-LOX inhibitory activity of examined extracts was reported for the first time (IC(50)=0.75 and 1.73 mg/ml for P. lanceolata and P. major, respectively). Although renowned inhibitors, such as acetylsalicylic acid and quercetin showed higher activity, this study verifies P. lanceolata and P. major as considerable anti-inflammatory agents.

Plantain (Plantago L.) species as novel sources of flavonoid antioxidants.

To examine the antioxidant properties of methanol extracts of selected Plantago species (P. argentea Chaix., P. holosteum Scop., P. major L., P. maritima L., and P. media L.), various assays that measure free radical scavenging ability were carried out: DPPH, hydroxyl radical, superoxide anion, and nitric oxide scavenger capacity tests, reducing power (FRAP) assay, and Fe(2+)/ascorbate induced lipid peroxidation. In all of the tests extracts showed a potent antioxidant effect compared with BHT, a well-known synthetic antioxidant, and the extract of P. major, accepted as an official remedy. Besides, in examined extracts the total phenolic amount (ranging from 38.43 to 70.97 mg of GAE/g of dw) and the total flavonoid content (5.31-13.10 mg of QE/g of dw) were determined. Furthermore, the presence and content of selected flavonoids (luteolin-7-O-glucoside, apigenin-7-O-glucoside, luteolin, apigenin, rutin, and quercetin) were studied using LC-MS/MS technique. LC-MS/MS analysis showed noticeable qualitative and quantitative differences between the species according to which the examined Plantago species could be regarded as a possible new source of natural antioxidants. In this study three of the species examined, P. maritima, P. argentea, and P. holosteum, have been analyzed for the first time.