Phytochemical Study of Stachys iva Griseb. and In Vitro Evaluation of AhR Transcriptional Activity.

Genus Stachys L. consists of approximately 365 species, distributed mainly in temperate regions. Several members of this genus are widely used in the traditional medicine of different countries worldwide. In Greece, 54 Stachys taxa are found in parts of the mainland and/or insular country. The present study focused on the phytochemical investigation of Stachys iva Griseb. and the in vitro anti-inflammatory evaluation of the isolated compounds. In total, eighteen compounds were isolated and identified from the dichloromethane-methanol extract, belonging to iridoids, flavonoids, phenylethanoid glycosides, and phenolic acids. An in vitro approach assessed the aryl hydrocarbon receptor (AhR) modulatory effects of these compounds, revealing an AhR agonistic activity of the flavonoid aglycones apigenin and cirsimaritin in HepG2 and HT29 cell lines. The present study contributes to the evidence of the traditional uses of Stachys spp. and its bioactive constituents, justifying the ethnopharmacological use as an anti-inflammatory plant genus.

Chemometric Analysis Evidencing the Variability in the Composition of Essential Oils in 10 Salvia Species from Different Taxonomic Sections or Phylogenetic Clades.

Essential oil (EO) of Salvia spp. has been widely used for culinary purposes and in perfumery and cosmetics, as well as having beneficial effects on human health. The present study aimed to investigate the quantitative and qualitative variations in EOs in wild-growing and cultivated pairs of samples from members in four Salvia sections or three clades, namely S. argentea L. (Sect. Aethiopis; Clade I-C), S. ringens Sm. (Sect. Eusphace; Clade I-D), S. verticillata L. (Sect. Hemisphace; Clade I-B), S. amplexicaulis Lam., and S. pratensis L. (Sect. Plethiosphace; Clade I-C). Furthermore, the natural variability in EO composition due to different genotypes adapted in different geographical and environmental conditions was examined by employing members of three Salvia sections or two phylogenetic clades, namely S. sclarea L. (six samples; Sect. Aethiopis or Clade I-C), S. ringens (three samples; Sect. Eusphace or Clade I-D), and S. amplexicaulis (five samples; Sect. Plethiosphace or Clade I-C). We also investigated the EO composition of four wild-growing species of two Salvia sections, i.e., S. aethiopis L., S. candidissima Vahl, and S. teddii of Sect. Aethiopis, as well as the cultivated material of S. virgata Jacq. (Sect. Plethiosphace), all belonging to Clade I-C. The EO composition of the Greek endemic S. teddii is presented herein only for the first time. Taken together, the findings of previous studies are summarized and critically discussed with the obtained results. Chemometric analysis (PCA, HCA, and clustered heat map) was used to identify the sample relationships based on their chemical classes, resulting in the classification of two distinct groups. These can be further explored in assistance of classical or modern taxonomic Salvia studies.

Consumption of herbal infusions/decoctions and tea in Greece: a Planeterranean perspective on the results of Hydria survey.

BACKGROUND: The consumption of various herbal infusions was and is common in the traditional Mediterranean diet, and apparently are used in many other regions of the world outside of the Mediterranean region. The present study aimed to investigate the consumption of herbal infusions/decoctions and tea in a nationally representative sample of Greece, considering also their Planetary use. METHODS: 3951 adult participants of the HYDRIA Survey (2013-2014) were included from the 13 regions of Greece. The diet of participants was assessed by two 24-h dietary recalls (24-HDR) and the Food Propensity Questionnaire (FPQ). All food items were analyzed through the HYDRIA Food Composition Tables. Information on socio-demographics, lifestyle, and health characteristics during the baseline was also provided. RESULTS: 26.9% of herbal infusions and decoctions consumers are ≥ 75 years old, pensioners with a low level of education, and residents of urban areas. However, 22.2% of tea consumers belong to the 18-34-year age group, being employed with an intermediate level of education and living in an urban area. Elderly men and women use more herbal infusions/decoctions (55.4%; 40.6%) compared to tea (41.8%; 25.2%). According to FPQ, 7.1% of men and 9.7% of women use herbal infusions and decoctions four times or more per week, while 7.1 and 10.9% of men and women, respectively, consume tea at the same frequency. Green tea, mountain tea (Sideritis spp.), and black tea are reported most frequently. In addition, mountain tea (61.2%), black tea (60.3%), mixed herbal infusions/decoctions (58.4%), and sage (59.4%) are consumed mostly at breakfast, while chamomile was reported mainly at dinner or during the night (42.4%). CONCLUSIONS: Based on the FPQ results, the moderate and high consumption of herbal infusions/decoctions and tea is low in Greece, especially among adults (18-64 years). Thus, our results indicate the existence of a generation gap to the attachment to the traditional Med Diet and the consumption of herbal infusions. The present study could encourage future research to focus on herbal infusions and decoctions consumption by other populations for cross-cultural comparison, as well as on emphasizing the value of consuming locally available herbs in a Planeterranean perspective.

Metabolic Fingerprinting of Different Sideritis Taxa Infusions and Their Neurogenic Activity.

Over the last years, Sideritis extracts were shown to improve memory. However, their potential to promote the generation of new neurons, starting with the neuronal differentiation of neural stem cells, remains unexplored. Therefore, the present study aimed to evaluate the neurogenic effects of different Sideritis infusions in neural stem and precursor cells and their impact on cell viability. Moreover, the metabolic fingerprints were recorded using LC-DAD, LC-HRESIMS, and GC-MS. The neurogenic potential of infusions of the eight Sideritis taxa tested was as potent as the classical neuronal inducer combination of retinoic acid and valproic acid. Further cytotoxicity assays revealed that the IC50 values of the extracts were between 163 and 322 µg/mL. Hierarchical cluster analyses of the metabolic fingerprints unveiled that the two Sideritis taxa with the lowest IC50 values were the most divergent in the analytical techniques used. As the analysis focused on polyphenols, it is reasonable to assume that these compounds are responsible for the effect on the cell viability of SH-SY5Y neuroblastoma cells. This study is the first report on the neurogenic potential of Sideritis taxa and might support the use of Sideritis herbal preparations in the context of neurodegenerative diseases.

Bio-Actives from Natural Products with Potential Cardioprotective Properties: Isolation, Identification, and Pharmacological Actions of Apigenin, Quercetin, and Silibinin.

Cardiovascular diseases (CVDs) are the leading cause of morbidity and mortality worldwide. As a result, pharmaceutical and non-pharmaceutical interventions modifying risk factors for CVDs are a top priority of scientific research. Non-pharmaceutical therapeutical approaches, including herbal supplements, have gained growing interest from researchers as part of the therapeutic strategies for primary or secondary prevention of CVDs. Several experimental studies have supported the potential effects of apigenin, quercetin, and silibinin as beneficial supplements in cohorts at risk of CVDs. Accordingly, this comprehensive review focused critically on the cardioprotective effects/mechanisms of the abovementioned three bio-active compounds from natural products. For this purpose, we have included in vitro, preclinical, and clinical studies associated with atherosclerosis and a wide variety of cardiovascular risk factors (hypertension, diabetes, dyslipidemia, obesity, cardiac injury, and metabolic syndrome). In addition, we attempted to summarize and categorize the laboratory methods for their isolation and identification from plant extracts. This review unveiled many uncertainties which are still unexplored, such as the extrapolation of experimental results to clinical practice, mainly due to the small clinical studies, heterogeneous doses, divergent constituents, and the absence of pharmacodynamic/pharmacokinetic analyses.

Bio-Guided Investigation of Sideritis cypria Methanol Extract Driven by in Vitro Antioxidant and Cytotoxic Assays.

Sideritis cypria Post is an endemic and endangered species of Northern Cyprus. The overall aim of the present study was to evaluate the total phenolic content, the antioxidant, the cytotoxic and the antimicrobial activity of the methanol extract obtained from the aerial parts of cultivated S. cypria. A bio-guided approach led to the isolation of 27 chemical compounds by using various analytical techniques. Their structures were elucidated on the basis of 1D and 2D NMR spectroscopy. The crude extract exerted strong antioxidant activity (DPPH and FRAP assays) which was attributed to its high total phenolic content. Furthermore, groups rich in phenolic content showed highest antioxidant property, whereas groups with phytosterols, diterpenoids and apigenin derivatives exerted cytotoxic effects in MDA-MB231 cancer cell line by the MTT method. Moreover, the cytotoxic activity of four isolated apigenin derivatives was evaluated in the same cancer cells. The antimicrobial activity of the extract and groups were measured, demonstrating lack of activity. To the best of our knowledge, this survey is the first report on the biological activities of the methanol extract of S. cypria.

Nanovesicles Loaded with Origanum onites and Satureja thymbra Essential Oils and Their Activity against Food-Borne Pathogens and Spoilage Microorganisms.

Food poisoning is a common cause of illness and death in developing countries. Essential oils (EOs) could be effective and safe natural preservatives to prevent and control bacterial contamination of foods. However, their high sensitivity and strong flavor limit their application and biological effectiveness. The aim of this study was firstly the chemical analysis and the antimicrobial evaluation of the EOs of Origanum onites L. and Satureja thymbra L. obtained from Symi island (Greece), and, secondly, the formulation of propylene glycol-nanovesicles loaded with these EOs to improve their antimicrobial properties. The EOs were analyzed by GC-MS and their chemical contents are presented herein. Different nanovesicles were formulated with small average sizes, high homogeneity, and optimal ζ-potential. Microscopic observation confirmed their small and spherical shape. Antibacterial and antifungal activities of the formulated EOs were evaluated against food-borne pathogens and spoilage microorganisms compared to pure EOs. Propylene glycol-nanovesicles loaded with O. onites EO were found to be the most active formulation against all tested strains. Additionally, in vitro studies on the HaCaT cell line showed that nanovesicles encapsulated with EOs had no toxic effect. The present study revealed that both EOs can be used as alternative sanitizers and preservatives in the food industry, and that their formulation in nanovesicles can provide a suitable approach as food-grade delivery system.

Anti-Ageing Potential of S. euboea Heldr. Phenolics.

In recent years, the use of Sideritis species as bioactive agents is increasing exponentially. The present study aimed to investigate the chemical constituents, as well as the anti-ageing potential of the cultivated Sideritis euboea Heldr. The chemical fingerprinting of the ethyl acetate residue of this plant was studied using 1D and 2D-NMR spectra. Isomeric compounds belonging to acylated flavone derivatives and phenylethanoid glycosides were detected in the early stage of the experimental process through 2D-NMR techniques. Overall, thirty-three known compounds were isolated and identified. Some of them are reported for the first time not only in S. euboea, but also in genus Sideritis L. The anti-ageing effect of the ethyl acetate residue and the isolated specialized products was assessed as anti-hyaluronidase activity. In silico docking simulation revealed the interactions of the isolated compounds with hyaluronidase. Furthermore, the in vitro study on the inhibition of hyaluronidase unveiled the potent inhibitory properties of ethyl acetate residue and apigenin 7-O-ß-d-glucopyranoside. Though, the isomers of apigenin 7-O-p-coumaroyl-glucosides and also the 4'-methyl-hypolaetin 7-O-[6'''-O-acetyl-ß-d-allopyranosyl]-(1→2)-ß-d-glucopyranoside exerted moderate hyaluronidase inhibition. This research represents the first study to report on the anti-hyaluronidase activity of Sideritis species, confirming its anti-inflammatory, cytotoxic and anti-ageing effects and its importance as an agent for cosmetic formulations as also anticancer potential.

NMR analysis of cultivated Sideritis euboea Heldr.

INTRODUCTION: Over the last decades, the demand of medicinal plants has vastly increased. The health trend and social changes are leading to a growing demand for herbal products, as medicines and in particular as food supplements. Various cultivations of medicinal plants have been developed in order not only to respond on this enormous market, but also to offer high-quality products. Cultivated plants have attracted great scientific interest for their rich and high standard chemical compositions. OBJECTIVE: Our study focuses on the phytochemical profile of cultivated Sideritis euboea Heldr., a shrub with a great commercial value. The whole isolation course of all extracts, fractions and sub-fractions was continuously monitored and traced down using an NMR strategy, which permitted their detail characterisation and enabled us to choose the more abundant extract. METHODS: Aerial parts of cultivated S. euboea were extracted with solvents of increasing polarity and their secondary metabolites were identified by NMR analyses. RESULTS: So far, using various analytical methods, 16 secondary metabolites have been isolated from the methanol extract; two iridoids, seven flavones, five phenylethanoid glucosides and two phenolic acids. In addition to the previous investigation of the wild population, the present study revealed that its chemical profile is similar and even richer in phenolic compounds. CONCLUSION: The metabolic profile of cultivated S. euboea was studied through 1 H-NMR spectra; the structures of the isolated secondary metabolites were assigned based on their one-dimensional and two-dimensional NMR spectra. The NMR strategy allowed us to detect even the minor compounds in the extracts.

NMR-Based Chemical Profiling, Isolation and Evaluation of the Cytotoxic Potential of the Diterpenoid Siderol from Cultivated Sideritis euboea Heldr.

Diterpenes are characteristic compounds from the genus Sideritis L., possessing an array of biological activities. Siderol is the main constituent of the ent-kaurene diterpenes in Sideritis species. In order to isolate the specific compound and evaluate for the first time its cytotoxic activity, we explored the dichloromethane extract of cultivated Sideritis euboea Heldr. To track the specific natural bioactive agent, we applied NMR spectroscopy to the crude plant extract, since NMR can serve as a powerful and rapid tool both to navigate the targeted isolation process of bioactive constituents, and to also reveal the identity of bioactive components. Along these lines, from the rapid 1D 1H NMR spectrum of the total crude plant extract, we were able to determine the characteristic proton NMR signals of siderol. Furthermore, with the same NMR spectrum, we were able to categorize several secondary metabolites into chemical groups as a control of the isolation process. Therefore, this non-polar extract was explored, for the first time, revealing eleven compounds-one fatty acid ester; 2-(p-hydroxyphenyl)ethylstearate (1), three phytosterols; ß-sitosterol (2), stigmasterol (3), and campesterol (4); one triterpenoid; ursolic acid (5), four diterpenoids; siderol (6), eubol (7), eubotriol (8), 7-epicandicandiol (9) and two flavonoids; xanthomicrol (10) and penduletin (11). The main isolated constituent was siderol. The antiproliferative potential of siderol was evaluated, using the MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) assay, on three human cancer cell lines DLD1, HeLa, and A549, where the IC50 values were estimated at 26.4 ± 3.7, 44.7 ± 7.2, and 46.0 ± 4.9 µΜ, respectively. The most potent activity was recorded in the human colon cancer cell line DLD1, where siderol exhibited the lowest IC50. Our study unveiled the beneficial potential of siderol as a remarkable cytotoxic agent and the significant contribution of NMR spectroscopy towards the isolation and identification of this potent anticancer agent.

Comparative phytochemical analysis of cultivated and wild Sideritis raeseri Boiss. & Heldr. subsp. raeseri infusions.

The present study focuses on the chemical composition of the infusions of Sideritis raeseri subsp. raeseri from cultivated and wild populations using NMR, LC-DAD, LC-HRESIMS, and GC-MS techniques, to reveal possible differences. Mainly carbohydrates, flavonoids, and phenylethanoid glycosides were detected in the 1H-NMR spectra of both infusions. In the GC-MS analysis, carbohydrates were shown to be the main constituents in both infusions. Caffeic acid was found in traces only in the cultivated sample, while quinic and chlorogenic acids were detected in both samples. Further investigation by LC-HRESIMS unveiled the same constituents with only slight differences in the amounts. Although the Sideritis samples originated from wild and cultivated populations, similar metabolic profiles were observed in the infusions.

NMR-guided isolation of undescribed triterpenoid saponins from Lysimachia atropurpurea L.

Phytochemical investigation on aerial parts of Lysimachia atropurpurea L. (Myrsinaceae), guided by NMR methods, resulted in the isolation and characterization of three previously undescribed triterpenoid saponins named stralysaponins A-C along with five known compounds. Their structures were elucidated by 1D and 2D NMR spectroscopy and HR-ESI-MS. Stralysaponins A-C were categorized into 13ß-28-epoxyoleanane-type triterpenoid saponins, reaffirming their prevalent presence of this type in the Myrsinaceae family and the genus Lysimachia. The identified derivatives share a common four-unit branched sugar chain, with rhamnose as the terminal sugar linked at C-3 of the aglycone. The presence of triterpenoid saponins in L. atropurpurea is reported herein for the first time. This study enriched the chemical diversity of triterpenoid saponins of the genus Lysimachia. Additionally, it demonstrates the effectiveness of NMR-profiling in isolating previously undescribed triterpenoid saponins from Lysimachia spp.

Phytochemical Profiles and Biological Activities of Plant Extracts from Aromatic Plants Cultivated in Cyprus.

Medicinal and aromatic plants' properties, still an interesting research area, are attributed to the presence of various specialized products that possess important pharmacological activities. In the present study, six medicinal/aromatic plants (Sideritis cypria, Origanum dubium, Melissa officinalis, Mentha piperita, Thymus capitatus, and Salvia fruticosa) were evaluated for their phytochemical and nutritive composition, as well as their biological activities, including antioxidant, antimicrobial, and cytotoxic properties. The results obtained indicate that M. piperita was rich in proteins and minerals such as N and Mg, while S. cypria accumulated more K, Na, P, and Ca. The highest content of phenols and flavonoids was observed in M. piperita, followed by O. dubium and T. capitatus, which eventually influenced their high antioxidant capacity. NMR screening revealed the presence of (i) triterpenoids and hydroxycinnamic acid derivatives in M. officinalis; (ii) terpenoids, flavonoids, and phenolic acid derivatives in S. fruticosa; (iii) flavonoids and phenolic acid derivatives in M. piperita; (iv) phenolic monoterpenes in O. dubium and T. capitatus; and (v) terpenoids, flavones, and phenylethanoid glycosides in S. cypria. The results of the antimicrobial activity showed that the tested samples overall had quite good antimicrobial potential. High antibacterial activity was found in O. dubium and T. capitatus, while O. dubium and S. cypria exhibited great antifungal activities. The studied species also had an important effect on the viability of female-derived and colon cancer cells. In particular, in colon cancer cells, the extracts from T. capitatus, M. officinalis, M. piperita, and S. fruticosa exhibited a stronger effect on cell viability in the more metastatic cell line at significantly lower concentrations, indicating an important therapeutic potential in targeting highly metastatic tumors. This finding is worth further investigation. The present study unveiled interesting phytochemical profiles and biological properties of the six medicinal/aromatic plants, which should be further explored, contributing to green chemistry and the possible creation of natural health products for humans' health/nutrition and additives in cosmetics.

Sideritis L. essential oils: A systematic review.

Essential oils are extensively used in the food, cosmetic, perfume, pharmaceutical, and agrochemical industries due to their aroma and pharmacological properties. The Lamiaceae family is mainly represented by widely well-known medicinal and aromatic plants that produce essential oil. Over the years, Sideritis L. essential oils have attracted great interest due to their chemical variability among the different taxa and their pharmacological activities. In-depth research of previously published literature was performed on electronic databases with several key search words for the collection of the available data and a total of 128 scientific studies were used since 1983. To date, 155 accepted Sideritis samples have been studied originating from 15 countries and more than 250 compounds have been reported in 87 Sideritis taxa overall. Furthermore, antimicrobial and antioxidant effects have been the most studied pharmacological activities. This review summarizes and critically discusses the research work on the chemical composition and pharmacological activities of essential oil of the genus Sideritis based on the currently valid taxonomy. Additionally, statistical analysis is encompassed to provide a deeper comprehensive understanding of the high chemical polymorphism of Sideritis essential oils. We expect that this review will encourage researchers to investigate unexplored Sideritis taxa and will contribute to revealing uncharted scientific territory and future perspectives on these plants.

Recent Advances in Nanoformulations for Quercetin Delivery.

Quercetin (QUE) is a flavonol that has recently received great attention from the research community due to its important pharmacological properties. However, QUE's low solubility and extended first-pass metabolism limit its oral administration. This review aims to present the potential of various nanoformulations in the development of QUE dosage forms for bioavailability enhancement. Advanced drug delivery nanosystems can be used for more efficient encapsulation, targeting, and controlled release of QUE. An overview of the primary nanosystem categories, formulation processes, and characterization techniques are described. In particular, lipid-based nanocarriers, such as liposomes, nanostructured-lipid carries, and solid-lipid nanoparticles, are widely used to improve QUE's oral absorption and targeting, increase its antioxidant activity, and ensure sustained release. Moreover, polymer-based nanocarriers exhibit unique properties for the improvement of the Absorption, Distribution, Metabolism, Excretion, and Toxicology (ADME(T)) profile. Namely, micelles and hydrogels composed of natural or synthetic polymers have been applied in QUE formulations. Furthermore, cyclodextrin, niosomes, and nanoemulsions are proposed as formulation alternatives for administration via different routes. This comprehensive review provides insight into the role of advanced drug delivery nanosystems for the formulation and delivery of QUE.

Sustainable diets & medicinal aromatic plants in Greece: Perspectives towards climate change.

In recent years, climate change continuously concerns the scientific community about its effects on agrobiodiversity, food safety and human health. Remodeling to sustainable diets and lifestyles is proved to be the most radical need to tackle this grave phenomenon. The goals of this commentary are to present the Greek traditional Mediterranean diet as a principal sustainable diet, to emphasize the role of Medicinal and Aromatic Plants in Greece as indispensable components of this healthy dietary pattern, and to discuss the potential results of climate change at their phytochemical content. Moreover, the impact of climate challenge at the occurrence of Greek MAPs and their survival is also described. Multiple approaches for addressing this challenge are proposed, as well as recommendations for specific actions with a focus on Greek traditional Mediterranean diet and MAPs of Greece.

Polar constituents, biological effects and nutritional value of Sideritis sipylea Boiss.

The present study focuses on the polar constituents and biological effects of the methanol extract and the infusion of wild Sideritis sipylea Boiss. from Samos island (Greece), as well as on the nutritional and mineral contents of this plant. The total phenolic content and antioxidant activity were examined. In addition, the anti-acetylcholinesterase property was evaluated, revealing strictly lower results than the control, galanthamine. Furthermore, the nutritional value of the plant is reported herein for the first time, revealing a promising source of protein. To the best of our knowledge, this study is the first work on the infusion of this species and the nutritional value of the plant.

The genus Genista L.: A rich source of bioactive flavonoids.

The genus Genista L. (family Fabaceae, subfamily Papilionoideae), with its cosmopolitan distribution, has attracted the human interest since ancient times, as it is used in folk medicine and mainly in the Mediterranean area for the treatment of respiratory diseases, rheumatic disorders, diabetes and ulcer, while it is also well known for its yellow pigment. The chemical composition of the Genista species revealed the presence of more than 108 flavonoids. Isoflavones, belonging to the group of phytoestrogens, are important secondary metabolites of the genus. The extracts of the Genista species may act as important source of bioactive phytochemicals for the treatment of many human ailments, mainly inflammation and pain, estrogen related pathology, hyperglycaemia, cancer and microbial infections. Therefore, the present review summarizes and discusses the flavonoid derivatives from the genus Genista, together with their structural features and pharmacological properties, aiming to highlight the recent advances in current knowledge on Genista species as a source of bioactive flavonoids.

Valorisation of stachysetin from cultivated Stachys iva Griseb. as anti-diabetic agent: a multi-spectroscopic and molecular docking approach.

Stachys species are considered as important medicinal plants with numerous health benefit effects. In continuation of our research on the Greek Stachys species, the chemical profile of the aerial parts of cultivated S. iva Griseb. has been explored. The NMR profiles of the plant extract/infusion were used to guide the isolation process, leading to the targeted isolation of seventeen known compounds. The rare acylated flavonoid, stachysetin, was isolated for the third time from plant species in the international literature. Identification of the characteristic signals of stachysetin in the 1D 1H-NMR spectrum of the crude extract was presented. In order to evaluate the potential of the identified chemical space in Stachys to bear possible bioactivity against diabetes, we performed an in silico screening against 17 proteins implicated in diabetes, as also ligand based similarity metrics against established anti-diabetic drugs. The results capitalized the anti-diabetic potency of stachysetin. Its binding profile to the major drug carrier plasma protein serum albumin was also explored along with its photophysical properties suggesting that stachysetin could be recognized and delivered in plasma through serum albumin and also could be tracked through near-infrared imaging. Communicated by Ramaswamy H. Sarma.

Genus Stachys: A Review of Traditional Uses, Phytochemistry and Bioactivity.

The present review highlights that Stachys spp. consist an important source of bioactive phytochemicals and exemplifies the uncharted territory of this genus for new research studies.