Extracts of Sideritis scardica and Clinopodium vulgare Alleviate Cognitive Impairments in Scopolamine-Induced Rat Dementia.

Sideritis scardica Griseb. and Clinopodium vulgare L., belonging to the Lamiaceae family, are rich in terpenoids and phenolics and exhibit various pharmacological effects, including antioxidant, anti-inflammatory and anti-cancer activities. While the memory-enhancing impacts of S. scardica are well documented, the cognitive benefits of C. vulgare remain unexplored. This study assessed the potential effect of C. vulgare on learning and memory in healthy and scopolamine (Sco)-induced memory-impaired male Wistar rats, comparing it with the effects of S. scardica. Over a 21-day period, rats orally received extracts of cultivated S. scardica (200 mg/kg) and C. vulgare (100 mg/kg), either individually or in combination, with administration starting 10 days before and continuing 11 days simultaneously with Sco injection at a dose of 2 mg/kg intraperitoneally. The results showed that both extracts effectively mitigated Sco-induced memory impairment. Their combination significantly improved recognition memory and maintained monoaminergic function. S. scardica excelled in preserving spatial working memory, while C. vulgare exhibited comparable retention of recognition memory, robust antioxidant activity and acetylcholinesterase inhibitory activity. The extracts alleviated Sco-induced downregulation of p-CREB/BDNF signaling, suggesting neuroprotective mechanisms. The extract combination positively affected most of the Sco-induced impairments, underscoring the potential for further investigation of these extracts for therapeutic development.

Pomegranate peel, chokeberry leaves and Ironwort extract as novel natural inhibitors of amylin aggregation and cellular toxicity in pancreatic ß cells.

Impeding or reducing human amylin aggregation and/or its toxicity can be key to preventing pancreatic islet amyloidosis and ß-cell loss in patients with Type 2 Diabetes Mellitus (T2DM). Here, Punica granatum (pomegranate) peel, Sideritis raeseri (ironwort) and Aronia melanocarpa (chokeberry) leaf extracts, were tested for their novel anti-aggregative and antitoxic properties in human amylin (hIAPP) treated rat pancreatic insulinoma (INS) cells. The protein aggregation (Th-T) assay revealed an inhibitory trend of all three plant extracts against amylin aggregates. In agreement with this finding, pomegranate peel and ironwort extracts effectively prevented the transition of hIAPP from disordered, random coil structures into aggregation prone ß-sheet enriched molecular assemblies, revealed by CD spectroscopy. Consistent with their anti-aggregative action, all three extracts prevented, to various degrees, reactive oxygen species (ROS) accumulation, mitochondrial stress, and, ultimately, apoptosis of INS cells. Collectively, the results from this study demonstrate effectiveness of natural products to halt hIAPP aggregation, redox stress, and toxicity, which could be exploited as novel therapeutics against amylin-derived islet amyloidosis and ß-cell stress in T2DM.

Endemic Mountain Tea (Sideritis dichotoma Huter): Antioxidant and Antibacterial Activities, Mineral Content by ICP-MS and Phytochemical Content by LCHR-MS.

Endemic Sideritis dichotoma Huter, herbal tea, is used for colds, coughs and digestive ailments. Since at least 25 % of the active ingredients of pharmacological drugs are obtained from plants, it is important to investigate many plants, both traditionally used and whose potential hasnt yet been discovered, before they disappear. When the results compared to other Sideritis species, it has better antioxidant activity in DPPH⋅ scavenging activity, Fe3+ and Cu2+ reducing capacity methods and is also rich in minerals, necessary for human body, K, Mg, Ca, P, S. Zone values (10-19,5 mm) obtained on S. aureus, P. aeruginosa, E. coli, S.enteritidis, E. faecalis, P. putida and K. pnemoniae strains are an indication that the plant has antibacterial activity. 27 secondary metabolites were identified by LC-HRMS. Verbascoside, pharmacologically active compound known to have antitumor effect, cytotoxic selectivity and anticancer activity, is the most abundant phenolic in ethanol extract (49297.13 mg/kg).

Screening of Volatile Compounds, Traditional and Modern Phytotherapy Approaches of Selected Non-Aromatic Medicinal Plants (Lamiaceae, Lamioideae) from Rtanj Mountain, Eastern Serbia.

Ironwort (Sideritis montana L.), mountain germander (Teucrium montanum L.), wall germander (Teucrium chamaedrys L.), and horehound (Marrubium peregrinum L.) are species widely distributed across Europe and are also found in North Africa and West Asia. Because of their wide distribution they express significant chemical diversity. For generations, these plants have been used as medical herbs for treating different aliments. The aim of this paper is to analyze volatile compounds of four selected species that belong to the subfamily Lamioideae, family Lamiaceae, and inspect scientifically proven biological activities and potential uses in modern phytotherapy in relation to traditional medicine. Therefore, in this research, we analyze the volatile compounds from this plants, obtained in laboratory by a Clevenger-type apparatus, followed by liquid-liquid extraction with hexane as the solvent. The identification of volatile compounds is conducted by GC-FID and GC-MS. Although these plants are poor in essential oil, the most abundant class of volatile components are mainly sesquiterpenes: germacrene D (22.6%) in ironwort, 7-epi-trans-sesquisabinene hydrate (15.8%) in mountain germander, germacrene D (31.8%) and trans-caryophyllene (19.7%) in wall germander, and trans-caryophyllene (32.4%) and trans-thujone (25.1%) in horehound. Furthermore, many studies show that, in addition to the essential oil, these plants contain phenols, flavonoids, diterpenes and diterpenoids, iridoids and their glycosides, coumarins, terpenes, and sterols, among other active compounds, which affect biological activities. The other goal of this study is to review the literature that describes the traditional use of these plants in folk medicine in regions where they grow spontaneously and compare them with scientifically confirmed activities. Therefore, a bibliographic search is conducted on Science Direct, PubMed, and Google Scholar to gather information related to the topic and recommend potential applications in modern phytotherapy. In conclusion, we can say that selected plants could be used as natural agents for promoting health, as a source of raw material in the food industry, and as supplements, as well as in the pharmaceutical industry for developing plant-based remedies for prevention and treatment of many diseases, especially cancer.

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.

Phenolic Compounds, Antioxidant and Antibacterial Activities of Extracts from Aerial Parts of Thymus zygis subsp. gracilis, Mentha suaveolens and Sideritis incana from Morocco.

Thymus zygis subsp. gracilis, Mentha suaveolens and Sideritis incana (Lamiaceae family) are well recognized for their medicinal, pharmaceutical and aromatic properties. The present study aimed to investigate for the first time the phenolic composition, the antioxidant and antibacterial properties of the extracts obtained from the aerial parts of these species collected from the Ifrane region of Morocco. The phenolic compounds were determined using high-performance liquid chromatography coupled to photodiode array and electrospray ionization mass spectrometry (HPLC-PDA-ESI/MS). The antioxidant activity was investigated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, reducing power and ferrous ion chelating assays. The antibacterial activity was evaluated against three Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa and Salmonella typhimurium) and three Gram-positive bacteria (Staphylococcus aureus, Enterococcus faecalis and Listeria monocytogenes). A total of thirty-three, sixteen and thirteen phenolic compounds were positively identified and characterized in T. zygis subsp. gracilis, M. suaveolens and S. incana extracts, respectively. Among the extracts, M. suaveolens exhibited the highest antioxidant activity, followed by S. incana and T. zygis subsp. gracilis in both DPPH and reducing power assays; all extracts showed the lowest activity in the chelating assay. In addition, all extracts demonstrated a bactericidal effect against Gram-positive bacteria and bacteriostatic effect against Gram-negative bacteria. Therefore, the aerial parts of Moroccan T. zygis subsp. gracilis, M. suaveolens and S. incana might be considered as a valuable source of natural antioxidant and antibacterial agents with potential application in food and pharmaceutical industries.

Optimization of Ultrasound-Assisted Extraction of Phenolics from Sideritis raeseri Using Response Surface Methodology.

In this study we define the optimal conditions for ultrasound-assisted extraction of bioactive polyphenols from S. raeseri aerial parts using response surface methodology. The influence of ethanol concentration (10-90%), extraction temperature (20-80 °C), extraction time (10-60 min), and solid-to-solvent ratio (1:10-1:50) on total phenolic content as well as on content of individual flavonoids, and hypolaetin and isoscutellarein derivatives was studied. For the experimental design, a central composite design was chosen. In the obtained extracts, the following ranges of targeted compounds were detected: total phenol from 19.32 to 47.23 mg GAE/g dw, HYP from 1.05 to 11.46 mg/g dw, ISC 1 from 0.68 to 10.68 mg/g dw, and ISC 2 from 0.74 to 15.56 mg/g dw. The optimal extraction conditions were set as: ethanol concentration of 65%, extraction time of 50 min, extraction temperature of 63 °C, and solid-to-solvent ratio of 1:40. Contents of TP, HYP, ISC 1, and ISC 2 in optimal extracts were 47.11 mg GAE/g dw, 11.73 mg/g dw, 9.54 mg/g dw, and 15.40 mg/g dw, respectively. Experimentally set values were in good agreement with those predicted by the response surface methodology model, indicating suitability of the used model, as well as the success of response surface methodology in optimizing the conditions of the extraction.

Sideritis perfoliata inhibits cell proliferation, induces apoptosis and exhibits cellular antioxidant activity in cervical cancer cells / Sideritis perfoliata inhibe la proliferación celular, induce apoptosis y exhibe actividad antioxidante celular en células de cáncer de cuello uterino

In this study, it was aimed to determine the antioxidant and anticancer activities of Sideritis perfoliata methanolic extract (SPE) on cervical cancer cells (HeLa). Different doses (25, 50,100 and 200 µg/mL) of SPE were used to determine proliferation of HeLa cells by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) staining method. Induction of apoptosis was determined by Annexine-V and propidium iodide staining method. Interleukin (IL) 6-8 levels were measured by ELISA method. Antioxidant activities of SPE were determined by DPPH, DNA (plasmid pBR322) protecting and cellular antioxidant activity tests. Some phytochemicals of SPE were also screened by LC-MS-MS. It was determined that SPE reduced the proliferation of HeLa cells and also induced apoptosis. IL6-8 levels importantly decreased at 200 µg/mL. SPE exhibited moderately antioxidant activities in tests used. Among the phenolics identified, vanillic acid had the highest amount. As a result, it was determined to have the anticancer activity of SPE by decreasing cell proliferation, inducing apoptosis and decreasing IL6-8 in HeLa cells.

En este estudio, se tuvo como objetivo determinar las actividades antioxidantes y anticancerígenas del extracto metanólico de Sideritis perfoliata (SPE) en las células de cáncer de cuello uterino (HeLa). Se utilizaron diferentes dosis (25, 50, 100 y 200 µg/mL) de SPE para determinar la proliferación de células HeLa mediante el método de tinción con bromuro de 3-[4,5-dimetiltiazol-2-il] -2,5-difenil-tetrazolio (MTT). La inducción de apoptosis se determinó mediante el método de tinción con anexina-V y yoduro de propidio. Los niveles de interleucina (IL) 6-8 se midieron mediante el método ELISA. Las actividades antioxidantes de SPE se determinaron mediante pruebas de DPPH, protección de ADN (plásmido pBR322) y actividad antioxidante celular. Algunos fitoquímicos de SPE también se analizaron mediante LC-MS-MS. Se determinó que SPE redujo la proliferación de células HeLa y también indujo apoptosis. Los niveles de IL6-8 disminuyeron de manera importante a 200 µg/mL. SPE mostró actividades moderadamente antioxidantes en las pruebas utilizadas. Entre los fenólicos identificados, el ácido vainílico tuvo la mayor cantidad. Como resultado, se determinó que tenía la actividad anticancerígena de SPE al disminuir la proliferación celular, inducir apoptosis y disminuir la IL6-8 en las células HeLa.

In vitro scolicidal effects of Sideritis perfoliata extract against Echinococcus granulosus.

BACKGROUND: Cystic echinococcosis, caused by helminths within the genus Echinococcus, is mainly localised in the liver and lungs of affected hosts. Surgery has been the best choice for the treatment of hydatidosis and using effective scolicidal agents during hydatid surgery is required to prevent secondary infection. Several plant extracts have been shown to exert scolicidal efficacy. This study was designed to investigate the in vitro scolicidal activity of methanol extract of Sideritis perfoliata against the protoscolices of hydatid cysts. METHODS: The protoscolices were collected from a liver of a sheep slaughtered in Adiyaman city slaughter, Turkey. Three concentrations of the aerial part extract of S perfoliata (0.1, 0.2 and 0.4 mg/mL) were assessed at three different exposure periods. All tests were carried in duplicate. The viability of protoscolices was assessed by the eosin exclusion test (0.1% eosin staining). RESULTS: Scolicidal effect of S perfoliata extract at exposure periods of 10, 20 and 30 minutes was 29.6%, 32.5% and 43.6% at the concentration of 0.1%, 37.8%, 50% and 58.1% at concentration of 0.2 mg/mL, and 57.9%, 71.8% and 79.1% at the concentration of 0.4 mg/mL, respectively; indicating a longer time is required to display protoscolicidal effects. LC-MS/MS analysis showed that some phenolic acids, such as fumaric acid (260.13 mg/L), syringic acid (27.92 mg/L) and caffeic acid (26.84 mg/L), and a flavonoid, luteolin (11.23 mg/L) were detected in high concentrations in the extract. CONCLUSIONS: This study has demonstrated that the methanol extract of S perfoliata has high scolicidal activity in vitro. However, research on the in vivo efficacy of S perfoliata extract and its potential side effects is required.

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.

Phytochemical Analysis, Antioxidant and Anticancer Potential of Sideritis niveotomentosa: Endemic Wild Species of Turkey.

Sideritis niveotomentosa Hub. -Mor. is a local endemic species belonging to the Lamiaceae family. In this study, GC/MS analysis, total antioxidant capacity and anticancer effects of different extracts obtained from S. niveotomentosa were investigated comparatively. Total phenolic contents of extracts were determined by the Folin-Ciocalteu method, total flavonoid contents by aluminum chloride method, and also the free radical scavenging activities of the extracts by DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) assay. The cytotoxic effect of the extracts was studied via MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) assay on DLD1, HL60 and ARH77 cell lines. Pro-apoptotic gene expression levels were also tested in the most sensitive cell line ARH77 by Real-Time PCR. The expression levels of 4 pro-apoptotic genes, APAF, BAX, CASP3, and HRK were found to be upregulated in ARH77 cells that were treated extracts. Results showed that methanolic extracts contain more phenolic content than acetone extracts, consistent with DPPH results. As a result, Sideritis niveotomentosa extracts, especially methanolic extracts, are rich in phenolic content and have a strong radical scavenging effect. In addition, the extracts showed selective effects on cell lines. This study is pioneering in terms of future studies, and the findings provide hope for future experimentation.

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.

Behavioral and Neurochemical Effects of Extra Virgin Olive Oil Total Phenolic Content and Sideritis Extract in Female Mice.

The aim of this study was to determine the cognitive and behavioral effects of extra virgin olive oil total phenolic content (TPC) and Sideritis (SID) extracts in female mice, and identify the associated neurochemical changes in the hippocampus and the prefrontal cortex. All animals received intraperitoneal low or high doses of TPC, SID or vehicle treatment for 7 days and were subjected to the Open Field (OF), Novel Object Recognition (NOR) and Tail Suspension Test (TST). The prefrontal cortex and hippocampus were dissected for analysis of neurotransmitters and aminoacids with high performance liquid chromatography with electrochemical detection (HPLC-ED). Both TPC doses enhanced vertical activity and center entries in the OF, which could indicate an anxiolytic-like effect. In addition, TPC enhanced non-spatial working memory and, in high doses, exerted antidepressant effects. On the other hand, high SID doses remarkably decreased the animals' overall activity. Locomotor and exploratory activities were closely associated with cortical increases in serotonin turnover induced by both treatments. Cognitive performance was linked to glutamate level changes. Furthermore, TPC reduced cortical taurine levels, while SID reduced cortical aspartate levels. TPC seems to have promising cognitive, anxiolytic and antidepressant effects, whereas SID has sedative effects in high doses. Both extracts act in the brain, but their specific actions and properties merit further exploration.

Polyphenols and Other Bioactive Compounds of Sideritis Plants and Their Potential Biological Activity.

Due to the growing problem of obesity associated with type 2 diabetes and cardiovascular diseases, causes of obesity are extensively investigated. In addition to a high caloric diet and low physical activity, gut microbiota disturbance may have a potential impact on excessive weight gain. Some reports indicate differences in the composition of the intestinal microflora of obese people in comparison to lean. Bioactive compounds of natural origin with beneficial and multifaceted effects on the body are more frequently used in prevention and treatment of many metabolic diseases including obesity. Sideritis scardica is traditionally consumed as mountain tea in the Balkans to strengthen the body and improve mood. Many reports indicate a positive effect on digestive system, weight loss, and prevention of insulin resistance. Additionally, it exhibits antioxidant activity and anti-inflammatory effects. The positive effect of Sideritis scardica extracts on memory and general cognitive abilities is indicated as well. The multilevel positive effect on the body appears to originate from the abundant occurrence of phenolic compounds, especially phenolic acids in Sideritis scardica extracts. However, mechanisms underlying their action require careful discussion and further research. Therefore, the objective of this review is to summarize the available knowledge on the role and mechanism of action of biologically active compounds of Sideritis scardica and other related species from the genus Sideritis.

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.

Cytotoxic and Anti-Inflammatory Effects of Ent-Kaurane Derivatives Isolated from the Alpine Plant Sideritis hyssopifolia.

This paper reports the isolation and structural characterization of four new ent-kaurane derivatives from the Lamiaceae plant Sideritis hyssopifolia. Planar structures and relative configurations were determined using both mass spectrometry and nuclear magnetic resonance (1D and 2D). Absolute configurations were determined by comparing experimental and theoretical electronic circular dichroism spectra. The cytotoxic and microbial activities of all new compounds were tested. Compounds that were non-cytotoxic were further evaluated for anti-inflammatory activity.

Phytochemical contents, antioxidant effects, and inhibitory activities of key enzymes associated with Alzheimer's disease, ulcer, and skin disorders of Sideritis albiflora and Sideritis leptoclada.

In this study, urease, tyrosinase, cholinesterase inhibitory, and antioxidant activities of various extracts of Sideritis albiflora and Sideritis leptoclada were determined together with the phytochemical contents. In addition, the fatty acid compositions and phenolic compounds were investigated by gas chromatography (GC), gas chromatography-mass spectrometry (GC-MS), and high performance liquid chromatography-diode array detector (HPLC-DAD). Rosmarinic acid and caffeic acid in both Sideritis species were identified as the most abundant phenolic compounds whereas palmitic acid was found as a major fatty acid. The acetone extract of S. leptoclada indicated the highest antioxidant activity in ß-carotene-linoleic acid (IC50 : 17.23 ± 0.11 µg/ml), DPPH• (IC50 : 28.14 ± 0.05 µg/ml) and ABTS•+ (IC50 : 15.18 ± 0.02 µg/ml) assays. The acetone extract of S. albiflora (A0.50 : 32.71 ± 0.44 µg/ml) was found as the best reductant in cupric reducing antioxidant capacity (CUPRAC) assay. Against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), only the hexane extracts of Sideritis species showed moderate inhibitory activity. Moreover, all extracts of S. albiflora and the hexane extract of S. leptoclada exhibited significantly higher urease inhibitory activity than that of thiourea. Further, in vivo activity studies on extracts and isolated constituents obtained from these species are needed to understand the activity in biological systems. PRACTICAL APPLICATIONS: Multiple pharmacological studies have proven that Sideritis species is precious with significant bioactive properties. This is the first comprehensive research to determine the enzyme inhibitory and antioxidant activities of various extracts of S. albiflora and S. leptoclada with phytochemical contents. Both Sideritis species were found to be rich in rosmarinic and caffeic acids. The acetone extracts showed the highest activity in terms of antioxidant activity, while the hexane extracts exhibited superior urease inhibitory activity. These results show that Sideritis species could be used as urease inhibitors' agents and source of antioxidants in food, pharmaceutical, and cosmetic industries.

Chemical fingerprints, antioxidant, enzyme inhibitory, and cell assays of three extracts obtained from Sideritis ozturkii Aytaç & Aksoy: An endemic plant from Turkey.

This study was geared towards assessing the possible antioxidant, enzyme inhibitory, and cytotoxic activities of ethyl acetate, methanol, and water extracts of Sideritis ozturkii Aytaç & Aksoy. The phytochemical profiles of the studied extracts were characterised by HPLC-MS/MS. The methanol extract, rich in phenolics (78.04 mg gallic acid equivalent/g), exhibited the strongest antioxidant activities. However, the ethyl acetate extract was the most active extract in the enzyme inhibitory assays. The water extract of S. ozturkii (1 mg/ml, 48 h incubation) slightly inhibited (22%) growth of human breast cancer cell line (MDA-MB-231 cells). On the other hand, the ethyl acetate and methanol extracts showed strong inhibition (98% and 97%, respectively) of MDA-MB-231 cells and caused apoptotic cell death. Scientific data generated from this study further appraises the multiple biological activities of plants belonging to the Sideritis genus. In addition, preliminary evidence gathered from the current investigation advocates for further studies geared towards the preparation of therapeutic formulations from S. ozturkii.

In Vitro Antioxidant, Antithrombotic, Antiatherogenic and Antidiabetic Activities of Urtica dioica, Sideritis euboea and Cistus creticus Water Extracts and Investigation of Pasta Fortification with the Most Bioactive One.

BACKGROUND: The present work evaluated the in vitro antioxidant, antithrombotic, antiatherogenic and antidiabetic activities of Urtica dioica, Sideritis euboea and Cistus creticus and investigated pasta fortification with the most bioactive one. The methods employed were total phenolic content (TPC) in mg of gallic acid equivalents per g of dried-herb, 2,2'-azino-bis(3-ethylbenzothiazoline- 6-sulfonic acid) (ABTS) free radical scavenging in mg of dried-herb, cupric reducing antioxidant capacity (CUPRAC) in micromol trolox equivalent per g of dried-herb, platelet aggregation inhibition (PAF-PAI); plasma oxidation inhibition (POxI); and alpha glucosidase inhibition (a-GaseI) all in mg of dried-herb. Pasta fortified with the most bioactive herb was also studied for the above activities. METHODS: Cistus creticus extract was more bioactive (p < 0.05) compared to Sideritis euboea and Urtica dioica in all but antithrombotic assay, where Sideritis euboea was superior to the others (TPC: 37.9 ± 0.56 versus 9.6 ± 0.83 and 5.4 ± 0.70; SA50-ABTS: 0.040 ± 0.001 versus 0.400 ± 0.010 and 0.520 ± 0.008; ACUPRAC: 860 ± 6.23 versus 170 ± 4.25 and 80 ± 3.63; IA50-PAF: 1.8 ± 0.14 versus 1.2 ± 0.10 and 5.2 ± 0.21; POxI: 0.095 ± 0.016 versus 0.216 ± 0.021 and 0.534 ± 0.029; IA50-aGase: 0.2 ± 0.01 versus 2.1 ± 0.16 and 1.7 ± 0.12). RESULTS: Fortified pasta with cistus creticus extract exhibited significantly higher levels (p < 0.05) in all assays compared to plain pasta (TPC: 0.392 ± 0.064 versus 0.137 ± 0.020; SA50-ABTS: 9.4 ± 0.2 versus 126.9 ± 2.7; ACUPRAC: 5.4 ± 0.5 versus 0.9 ± 0.1; IA50-PAF: 1.87 ± 0.04 versus 2.28 ± 0.06; POxI: 3.21 ± 0.18 versus 12.2 ± 0.73; IA50-aGase: 8.9 ± 1.1 versus 18.2 ± 0.9). CONCLUSION: The current findings add to the mounting evidence on the potential health benefits to be derived from consuming pasta fortified with herbal extracts and indicate that Cistus creticus could form an ideal raw material towards the production of fortified pasta with increased nutritional value.

Effects of Sideritis scardica Extract on Glucose Tolerance, Triglyceride Levels and Markers of Oxidative Stress in Ovariectomized Rats.

Menopause is characterized by deep metabolic disturbances, including decreased insulin sensitivity, adiposity, and changes in lipid profiles. Estrogen replacement therapy can partially reverse these changes, and while it is safe in most healthy postmenopausal women, there are still existing concerns regarding an increased risk for breast and endometrial cancer as well as a risk for cardiovascular and thromboembolic disease. Therefore, certain natural compounds with positive metabolic effects may be considered as a possible alternative or adjunctive treatment in patients not willing to take estrogens or patients with contraindications for estrogens. The aim of this study was to investigate the influence of Sideritis scardica (mountain tea) extract on metabolic disturbances induced by ovariectomy in rats. The study included 24 rats divided into three groups: ovariectomized rats treated with 200 mg/kg S. scardica extract for 24 weeks (n = 8), ovariectomized non-treated (n = 8), and Sham-operated (n = 8) rats. Food intake, weight gain, body composition, fasting glucose levels, response to oral glucose challenge, liver glycogen content, catalase activity, thiol groups, and malondialdehyde concentrations as well as AMP-activated protein kinase activity in liver cells were studied. Ovariectomized rats treated with S. scardica extract had lower blood triglycerides, reduced fasting glucose levels, as well lower glucose peaks after oral glucose challenge, increased liver glycogen content, and significantly higher catalase activity and thiol group concentration than non-treated ovariectomized rats. The ability of S. scardica extract to attenuate metabolic disturbances associated with ovariectomy was associated with the activation of AMP-activated protein kinase in liver cells.