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Quantitative nuclear magnetic resonance (qNMR) spectroscopy is known as an excellent alternative to chromatography-based mixture analysis. NMR spectroscopy is a non-destructive method, needs only limited sample preparation, and can be readily automated. A head-to-head comparison of qNMR to an ultra-high-performance liquid chromatography with diode array detection (uHPLC-DAD)-based quantitative analysis of six flavonolignan congeners (silychristin, silydianin, silybin A, silybin B, isosilybin A, and isosilybin B) of the Silybum marianum silymarin complex is presented. Both assays showed similar performance characteristics (linear range, accuracy, precision, and limits of quantitation) with analysis times below 30 min/sample. The assays were applied to industrial S. marianum extracts (AC samples) and to extracts locally prepared from S. marianum fruits (PL samples). An assay comparison by Bland-Altman plots (relative method bias AC samples, -0.1%; 2SD range, ±5.1%; relative method bias PL samples, -0.3%; 2SD range, ±7.8%) and Passing-Bablok regression analysis (slope and intercept for AC and PL samples not significantly different from 1.00 and 0.00, respectively; Spearman's coefficient of rank correlation, >0.99) did show that qNMR and uHPLC-DAD can be used interchangeably to quantitate flavonolignans in the silymarin complex.

The purpose of this study was to evaluate the response of estrogen target cells to a series of isoflavone glucosides and aglycones from Genista halacsyi Heldr. The methanolic extract of aerial parts of this plant was processed using fast centrifugal partition chromatography, resulting in isolation of four archetypal isoflavones (genistein, daidzein, isoprunetin, 8-C-β-D-glucopyranosyl-genistein) and ten derivatives thereof. 7-O-β-D-glucopyranosyl-genistein and 7,4΄-di-O-β-D-glucopyranosyl-genistein were among the most abundant constituents of the isolate. All fourteen, except genistein, displayed low binding affinity for estrogen receptors (ER). Models of binding to ERα could account for the low binding affinity of monoglucosides. Genistein and its glucosides displayed full efficacy in inducing alkaline phosphatase (AlkP) in Ishikawa cells, proliferation of MCF-7 cells and ER-dependent gene expression in reporter cells at low concentrations (around 0.3 μM). ICI182,780 fully antagonized these effects. The AlkP-inducing efficacy of the fourteen isoflavonoids was more strongly correlated with their transcriptional efficacy through ERα. O-monoglucosides displayed higher area under the dose-response curve (AUC) of AlkP response relative to the AUC of ERα-transcriptional response compared to the respective aglycones. In addition, 7-O-β-D-glucopyranosyl-genistein and 7,4΄-di-O-β-D-glucopyranosyl-genistein displayed estradiol-like efficacy in promoting differentiation of MC3T3-E1 cells to osteoblasts, while genistein was not convincingly effective in this respect. Moreover, 7,4΄-di-O-β-D-glucopyranosyl-genistein suppressed lipopolysaccharide-induced tumor necrosis factor mRNA expression in RAW 264.7 cells, while 7-O-β-D-glucopyranosyl-genistein was not convincingly effective and genistein was ineffective. However, genistein and its O-glucosides were ineffective in inhibiting differentiation of RAW 264.7 cells to osteoclasts and in protecting glutamate-challenged HT22 hippocampal neurons from oxidative stress-induced cell death. These findings suggest that 7-O-β-D-glucopyranosyl-genistein and 7,4΄-di-O-β-D-glucopyranosyl-genistein display higher estrogen-like and/or anti-inflammatory activity compared to the aglycone. The possibility of using preparations rich in O-β-D-glucopyranosides of genistein to substitute for low-dose estrogen in formulations for menopausal symptoms is discussed.

The processing of medicinal and aromatic plants (MAPs) results in the production of a significant amount of plant by-products; herbal material of inferior quality and/or unusable plant parts that are not commercially exploitable. An extensive study of Greek native species was performed toward the production of innovative bioactive products using as raw materials the by-products obtained from the processing of cultivated MAPs. Origanum vulgare subsp. hirtum (oregano), Sideritis scardica (Greek mountain tea), Thymus vulgaris (thyme), and Matricaria recutita (chamomile) were selected due to their wide use for the preparation of beverages and culinary purposes. The determination of the percentage of the post-harvest processing by-products was performed for a 3 years period (2018–2020). Results showed that by-products derived from the above-mentioned species' processing constitute 64% (thyme), 54% (oregano), 37% (Greek mountain tea), and 24% (chamomile) of the total processed mass. To value the by-products as a potent source of bioactive ingredients, superior and inferior quality herbal material of the aforementioned plant species were extracted by an ultrasonic assisted extraction method. Hydroalcoholic extracts were chemically investigated using high-performance thin layer chromatography (HPTLC) and liquid chromatography-mass spectrometry (LC-MS) techniques. In addition, their free radical scavenging activity and total phenolic content (TPC) were estimated. Based on the results, herbs by-products revealed similar chemical content to the superior herbal material by the means of HPTLC and LC-MS analysis. In addition, strong free radical scavenging related to a high phenolic content was detected in the case of thyme, oregano, and Greek mountain tea. Moreover, the gas chromatography-mass spectrometry (GC-MS) analyses of the essential oils (EOs) of oregano and thyme by-products revealed the presence of carvacrol, thymol, γ-terpinene, and p-cymene among the major constituents. Finally, the LC-MS analyses of aqueous extracts of Greek mountain tea and chamomile by-products led to the identification of several bioactive compounds, such as flavonoids and phenylpropanoids. Overall, the presence of bioactive constituents in by-products, such as terpenes, phenolic compounds, and flavonoids underly their potent use as food antimicrobial and antioxidant additives, in the preparation of high added-value products, such as enriched aromatic edible oils, and innovative herbal teas, such as instant beverages.

A review research was conducted to provide an overview of the ethnobotanical knowledge of medicinal plants and traditional medical practices for the treatment of skin disorders in Albania, Cyprus, Greece, and Turkey. The geographical and ecological characteristics of the Balkan Peninsula and Mediterranean Sea, along with the historical connection among those countries, gave rise to the development of a distinct flora and to the uses of common medicinal plants against various skin ailments, respectively. The review focuses on the detailed study of 128 ethnobotanical surveys conducted in these areas and the species used for skin ailments were singled out. The analysis showed that 967 taxa belonging to 418 different genera and 111 different families are used in the treatment of skin related problems. The majority of the plants belong to the families of Asteraceae (11.7%), Lamiaceae (7.4%), Rosaceae (6.7%), Plantaginaceae (5.4%), and Malvaceae (3.8%). Their usage is internal or external to treat ailments such as wounds and burns (22.1%), hemorrhoids (14.7%), boils, abscesses, and furuncles (8.2%). Beside specific skin disorders, numerous species appeared to be used for their antifungal, antimicrobial, and antiseptic activity (9.1%). Literature evaluation highlighted that, the most commonly used species are Plantago major L. (Albania, Turkey), Hypericum perforatum L. (Greece, Turkey), Sambucus nigra L. (Cyprus, Greece), Ficus carica L. (Cyprus, Turkey), Matricaria chamomilla L. (Cyprus, Greece), and Urtica dioica L. (Albania, Turkey), while many medicinal plants reported by interviewees were common in all four countries. Finally, to relate this ethnopharmacological knowledge and trace its expansion and diversification through centuries, a comparison of findings was made with the use of the species mentioned in Dioscorides’ “De Materia Medica” for skin disorders. This work constitutes the first comparative study performed with ethnobotanical data for skin ailments gathered in the South Balkan and East Mediterranean areas. Results confirm the primary hypothesis that people in Albania, Cyprus, Greece, and Turkey are closely related in terms of traditionally using folk medicinal practices. Nevertheless, more field studies conducted, especially in remote places of these regions, can help preserve the traditional medical knowledge, aiming at the discovery of new phytotherapeutics against dermatological diseases.

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Cynara cardunculus L. is a plant of the Mediterranean basin, known since antiquity as a food and for its therapeutic properties. The needs of the 21st century for the utilization of agricultural waste has led to the study of the seed oil of a Greek cultivar of Cynaracardunculus (GCCC) as potential nutritional oil, as large amounts of cardoon seeds are discarded. The sterol and fatty acid profile of cold-pressed seed oil was examined by gas chromatography-mass spectrometry GC-MS and compared with that of solvent extraction. Total phenolic content was determined and compared with well-known and widely appreciated edible vegetable oils; while, additionally, the total lignan content and nutritional value of cold-pressed oil revealed it as a potential dietary candidate. Furthermore, the seedcake (residue of cold-pressed oil extraction) has been studied exerting it as a good source of phenolics. Both GCCC oil and seedcake were tested for their antioxidant and enzyme inhibitory activities exhibiting higher activity compared to the sesame, flaxseed and extra virgin olive oils. According to the results, Cynara seed oil was shown to be a rich source of ω-6/-9 fatty acids and phenolics, highlighting, indicating that it could be a promising health-promoting vegetable oil, while the seedcake was revealed as a rich source of bioactive compounds.

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