Traditionally Used Sideritis cypria Post.: Phytochemistry, Nutritional Content, Bioactive Compounds of Cultivated Populations

An Innovative Approach to a Potential Neuroprotective Sideritis scardica-Clinoptilolite Phyto-Nanocarrier: In Vitro Investigation and Evaluation

The cutting-edge field of nanomedicine combines the power of medicinal plants with nanotechnology to create advanced scaffolds that boast improved bioavailability, biodistribution, and controlled release. In an innovative approach to performant herb nanoproducts, Sideritis scardica Griseb and clinoptilolite were used to benefit from the combined action of both components and enhance the phytochemical's bioavailability, controlled intake, and targeted release. A range of analytical methods, such as SEM-EDX, FT-IR, DLS, and XDR, was employed to examine the morpho-structural features of the nanoproducts. Additionally, thermal stability, antioxidant screening, and in vitro release were investigated. Chemical screening of Sideritis scardica Griseb revealed that it contains a total of ninety-one phytoconstituents from ten chemical categories, including terpenoids, flavonoids, amino acids, phenylethanoid glycosides, phenolic acids, fatty acids, iridoids, sterols, nucleosides, and miscellaneous. The study findings suggest the potential applications as a promising aspirant in neurodegenerative strategy.

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.

Chemical profile of the Anatolian Sideritis species with bioactivity studies

CONTEXT

The genus Sideritis L. (Lamiaceae) is represented by 46 species in Turkey with an 79% endemism ratio, 42 of 46 belonging to the section Empodoclia.

OBJECTIVE

In this review article, Sideritis species growing in Turkey have been evaluated for phytochemical constituents and biological activities.

METHODS

The data for the isolates, components and extracts of the Anatolian Sideritis species and their bioactivity studies were retrieved from the main databases WoS, Scopus and PubMed from 1975 until 31 December 2022.

RESULTS

In this review article, terpenoids, flavonoids, phenolics and other secondary metabolites isolated from Turkish Sideritis species were reported. Anatolian Sideritis species, which primarily consist of monoterpenes and sesquiterpenes, were studied in detail. Sideritis plants are represented by 46 species in Turkey, and 25 of them were investigated for their diterpenoids through isolation or LC-MS studies. Most of the diterpenoids of Turkish Sideritis species have ent-kaurene skeleton, among them linearol, siderol, 7-epicandicandiol and sideridiol were found to be the main compounds. Exceptionally, labdane, pimarane and beyerene diterpenoids were only found in a few species. For phenolics and flavonoids, only 12 species were investigated until now, and they were found to be rich in phenylethanoid glycosides and flavonoid glycosides. In terms of activity, most of the species were tested for antioxidant activity, followed by antimicrobial and anti-ulcer/anti-inflammatory activities. Their cytotoxic, enzyme inhibitory, antinociceptive and antistress activities were less frequently studied.

CONCLUSIONS

Sideritis species should be considered promising therapeutic agents in the treatment of upper respiratory tract and ulcer/inflammatory diseases.

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.

Leucosceptosides A and B: Two Phenyl-Ethanoid Glycosides with Important Occurrence and Biological Activities

In this review paper, the occurrence in the plant kingdom, the chemophenetic value and the biological activities associated with two specific phenyl-ethanoid glycosides, i.e., leucosceptoside A and leucosceptoside B, were reported. This is the first work ever conducted on such a subject. Analysis of the literature data clearly led to three important conclusions: leucosceptoside A is much more common in plants than leucosceptoside B; leucosceptoside A exerts more biological activities than leucosceptoside B even if nothing can be generally concluded about which one is actually the most potent; neither of these compounds can be used as a chemophenetic marker. These three aspects and more are discussed in more depth in this work.

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.

Advantages of Hyaluronic Acid and Its Combination with Other Bioactive Ingredients in Cosmeceuticals

This study proposes a review on hyaluronic acid (HA) known as hyaluronan or hyaluronate and its derivates and their application in cosmetic formulations. HA is a glycosaminoglycan constituted from two disaccharides (N-acetylglucosamine and D-glucuronic acid), isolated initially from the vitreous humour of the eye, and subsequently discovered in different tissues or fluids (especially in the articular cartilage and the synovial fluid). It is ubiquitous in vertebrates, including humans, and it is involved in diverse biological processes, such as cell differentiation, embryological development, inflammation, wound healing, etc. HA has many qualities that recommend it over other substances used in skin regeneration, with moisturizing and anti-ageing effects. HA molecular weight influences its penetration into the skin and its biological activity. Considering that, nowadays, hyaluronic acid has a wide use and a multitude of applications (in ophthalmology, arthrology, pneumology, rhinology, aesthetic medicine, oncology, nutrition, and cosmetics), the present study describes the main aspects related to its use in cosmetology. The biological effect of HA on the skin level and its potential adverse effects are discussed. Some available cosmetic products containing HA have been identified from the brand portfolio of most known manufacturers and their composition was evaluated. Further, additional biological effects due to the other active ingredients (plant extracts, vitamins, amino acids, peptides, proteins, saccharides, probiotics, etc.) are presented, as well as a description of their possible toxic effects.

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-β-d-glucopyranoside. Though, the isomers of apigenin 7-O-p-coumaroyl-glucosides and also the 4′-methyl-hypolaetin 7-O-[6′′′-O-acetyl-β-d-allopyranosyl]-(1→2)-β-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.

Structural study of a pectic polysaccharide fraction isolated from "mountain tea" (Sideritis scardica Griseb.)

The present study was conducted to investigate the structural characteristics of an acid-extracted polysaccharide fraction from mountain tea. The monosaccharide composition revealed that uronic acids (72.4 mol%) considerably predominated in the fraction, followed by smaller amounts of galactose (14.5 mol%) and glucose (6.2 mol%). The fraction contained mostly a highly methyl-esterified homogalacturonan (HG) - 71 mol%. The pectin had a high molecular weight population (∼60-100 kDa). Enzymatic fingerprinting was employed with a combination of HG degrading enzymes and LC-HILIC-MS, HPAEC, HPSEC to examine the structure in greater detail. Unsaturated oligomers released indicated the presence of large blocks of highly methyl-esterified GalA residues. Furthermore, the presence of blocks of non-esterified GalA residues and partly methyl-esterified and acetylated GalA residues in HG domain was demonstrated. The research findings provide a basis for further investigations regarding biological activity and commercial exploitation of mountain tea.

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.