Exploring Origanum dictamnus as a functional food ingredient: Phytochemical characterization and gut motility modulation.

This study aimed to validate the dermatological potential of Origanum dictamnus (dittany) infusion, traditionally recognized for its anti-inflammatory properties. To this end, 3D-printed hydrogel patches incorporating dittany were developed and evaluated for biocompatibility, wound-healing, anti-inflammatory activity, and effects on skin barrier. Hydrogel patches were fabricated via extrusion-based 3D printing using aloe vera gel, hydroxypropyl methylcellulose (HPMC), glycerol, and combinations of dittany infusion and panthenol. In vitro assays with HaCaT keratinocytes included cytotoxicity testing, scratch-wound healing, and qPCR-based analysis of inflammatory biomarkers. In vivo transepidermal water loss (TEWL) measurements were performed to assess skin barrier integrity and hydration after patch application. The traditional use of dittany infusion in skin ailments was confirmed, along with its relatively low cytotoxicity. Three 3D-printed gel types were evaluated in vitro, all showing superior performance to the raw plant extract. The optimal formulation contained 2% HPMC, 2% glycerol, 5% panthenol, and 0.06% dittany infusion (w/w% relative to aloe vera gel). At 3.25 mg/mL, this formulation achieved ~ 70% wound closure and significantly reduced IL-6 and TNF-α levels, indicating strong anti-inflammatory activity (p < 0.05). Both crude extract and patches show a trend toward reducing pro-inflammatory interleukins while simultaneously upregulating the anti-inflammatory cytokine IL-4. TEWL measurements indicated that none of the patches impaired the skin barrier function, confirming their compatibility with various skin types. This study provides the first scientific evidence that the incorporation of dittany infusion into 3D-printed hydrogels holds promise for safe, effective, plant-based topical therapies.

Origanum dictamnus L., is an aromatic plant belonging to Lamiaceae family. The aim of this study was to evaluate whether and how O. dictamnus essential oil (EO) showed inhibitory activity against enzymes associated with the Central Nervous System disorders and human metabolism. The EO was analyzed by GC/MS. Enzyme inhibitory activity against cholinesterases, tyrosinase, α-amylase, α-glucosidase and lipase were investigated. Lineweaver-Burk plots were constructed to study the kinetic parameters of the inhibitory activity. The interactions between the main constituents of the EO and enzymes were further analyzed through an in silico molecular docking study. The EO was mainly composed by carvacrol and p-cymene. The enzymatic assays showed inhibitory activities dependent on the EO concentrations. The type of inhibition observed was mixed for acetylcholinesterase, α-glucosidase, and lipase; competitive for butyrylcholinesterase; and non-competitive for tyrosinase. O. dictamnus EO could be used as supplement for management of metabolic and neurological disease.

Epilepsy manifests as recurrent spontaneous seizures associated with irregular brain activity. Recognizing the limitations of conventional antiepileptic treatments, we explored the therapeutic potential of essential oils (EOs) derived from Greek aromatic plants (Mentha pulegium, Mentha spicata wild, Mentha piperita, Lavandula angustifolia and Origanum Dictamnus). Specifically, we explored their radical scavenging capacity (DPPH), as well as their antioxidant (AOP and MDA levels) and neuroprotective effect in a PTZ-induced epilepsy Balb/c mice model (animals were pretreated with EOs prior to PTZ treatment). Our results indicated that Mentha piperita emerges as the most promising EO, demonstrating strong antioxidant activity and the highest radical scavenging ability (IC50 = 1.9 mg/mL). Mentha pulegium also exhibited considerable antioxidant potential, demonstrating the strongest effect in the AOP assay when administered prior to PTZ treatment. Furthermore, Origanum dictamnus exhibited the strongest potential to attenuate MDA formation in the presence of PTZ. Finally, immunohistochemistry indicated a trend of neuronal preservation in animals pretreated with EOs prior to PTZ, with Mentha piperita demonstrating the most significant effect. Based on these findings, we suggest that certain EOs possess significant antioxidant and neuroprotective properties. Further research is warranted to validate these results and elucidate the active ingredients responsible for the observed properties.

Origanum dictamnus infusion characterization by HPLC-PDA-MS and nanoformulation development

The growing negative environmental effects associated with chemical fertilizers have led to the promotion of organic fertilizers in agriculture. The purpose of this study was to evaluate the impacts of organic fertilization on nitrogen and phosphorus content, uptake and use efficiency in Origanum dictamnus (Dittany) cultivation. With this aim, a randomized complete blocks field experiment was carried out in Istron Kalou Xoriou (Agios Nikolaos—Crete). The study included three fertilization treatments (N0: 0 kg/ha−1, N1: 1250 kg/ha−1 and N2: 2500 kg/ha−1). Throughout the growing period, measurements were taken for the plant’s content, uptake and efficiency indices of total nitrogen (TN) and phosphorus (P). The findings indicated that the fertilization doses affect nutrient uptake and efficiency. The highest values of TN and P were recorded 60 days after transplants. N1 treatment showed the greatest improvement in nitrogen use efficiency, while phosphorus use efficiency reached its maximum level under N2 treatment. That research can contribute to achieving an in-depth insight of organic fertilization practices for aromatic and medicinal plants such as Dittany, promoting a sustainable agricultural strategy and enhancing product quality.

Νatural compounds such as lactic, acetic, formic, and oxalic acid and thymol are currently registered for use against Varroa destructor in apiaries in Europe. Complex botanical extracts are yet to be authorized, despite their beneficial ecofriendly profile and advantages in terms of resistance management. This study examined the fumigant activity of the essential oil (EO) of oregano, clove, lavender, dittany, bay laurel, sweet orange, peppermint, blue gum, and lemon balm against V. destructor in laboratory bioassays (Petri dishes). The most effective EOs were those of Origanum vulgare, Syzygium aromaticum, and Origanum dictamnus. These three EOs yielded 33.75% carvacrol, 58.64% eugenol, and 69.77% carvacrol and exhibited significant activity from 18 h of exposure to 0.0013 μL/cm until 48 h of exposure to 0.0068 μL/cm3. Origanum vulgare’s first calculated LC50 value was 0.003 μL/cm3 after 24 h of mites’ exposure to EO vapors. The LC50 values stabilized for oregano, clove, and dittany at 0.001, 0.002, and 0.002 μL/cm3 of 24 h exposure, respectively. This first indication of fumigant miticidal activity in Petri dishes is a promising first step before scaling up to field experiments.

Considering that urban horticulture benefits from green roof technology, the effects of substrate type (compost-perlite-pumice 3:3:4, v/v and compost-perlite-pumice-soil 3:3:2:2, v/v) and depth (7.5 cm and 15 cm) were comparatively evaluated in the cultivation of Crithmum maritimum and Origanum dictamnus on an urban green roof in modules that included a green roof infrastructure layering. During the first cultivation period (December 2015–August 2016), plants of C. maritimum were taller and had greater diameter than those of O. dictamnus. Greater fresh and dry weights of all plant parts were observed in C. maritimum, as well as in the deep substrates compared to the shallow ones. During the second cultivation period (September 2016–August 2017), the growth of O. dictamnus surpassed that of C. maritimum, while plant height and foliage diameter, as well as the fresh and dry weight of all plant parts were greater in the deep substrates for both species. Conclusively, both species grew satisfactorily on an extensive urban Mediterranean green roof, while the deep substrate favored all their growth parameters. O. dictamnus responded better in the soil-containing substrate regarding survival, growth, and flowering, as opposed to C. maritimum that showed equal response in both substrate types.

In this study, four depsides were isolated from Origanum dictamnus L. and Satureja pilosa Velen. medicinal plants and their structures were assessed by means of one-dimensional (1D)- and two-dimensional (2D)-nuclear magnetic resonance, high resolution mass spectrometry, and electronic circular dichroism analyses. The compound 1, herein reported for the first time, salvianolic acid P 2, clinopodic acid I 3, and clinopodic acid O 4 were all profiled in vitro on a panel of human (h) expressed carbonic anhydrases (CAs; EC 4.2.1.1) and preferential inhibition for the tumor-associated human carbonic anhydrase (hCA) IX and hCA XII over the constitutively expressed hCA I and hCA II isoforms was observed. X-ray crystallography allowed us to assess the binding mode of salvianolic acid P 2 to hCA II. The compounds exhibited significant cytotoxic effects on the human triple-negative breast cancer cell line MDA-MB-231, suggesting that this class of depsides are promising molecules for future investigation.

Medicinal and aromatic plants are a consistent component of the biodiversity heritage in numerous countries worldwide. Origanum dictamnus L. (Lamiaceae family), also known as Dittany, an endemic plant of the Greek island of Crete, has been widely used as traditional medicine since antiquity, all over Europe. The aim of the present review is to provide a thorough and detailed account of Dittany in antiquity, the plant’s physical characteristics and ecology, and its cultivation methods, as well as its chemical components, biological properties, and pharmacological studies. The information is presented and analyzed in a critical manner. A total of 86 research studies were systematically reviewed based on the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines. The findings indicate that Dittany is one of the most important medicinal and aromatic plants, with many uses not only in pharmacology but also in gastronomy. While a large body of literature exists regarding the application of essential oils, the number of publications concerning the plant’s cultivation is rather small. Therefore, the main focus of this review is on the cultivation methods and the significance of cultivating and employing Dittany in Greece and the wider Mediterranean region in the future. Further research on this plant species is warranted since it has significant medicinal, economic, and environmental value.

In recent years, there has been a growing tendency towards using organic fertilizers instead of chemical ones. This study aimed to evaluate the influence of the organic fertilizer, Prima Humica, on agronomic characteristics and herbaceous plant diversity on Origanum dictamnus (Dittany) cultivation. A field experiment was carried out in Kalo Xorio (Lasithi, Crete) and included three different nitrogen organic fertilization schemes: 0 g/plant (T0—unfertilized), 300 g/plot (T1), and 600 g/plot (T2). Plant height, fresh and dry weight, Leaf Area Index (LAI), and plant diversity during the growing season were measured. The results showed that when the T2 treatment was compared with the unfertilized and the T1 fertilizer, the increase in plant height ranged between 9.18% and 40.61%. Moreover, the total fresh and dry weight were positively affected by the T2 treatment. The total fresh and dry weight varied from 111.6 to 239.8 g per plant and from 36.7 to 77.6 g per plant, respectively. Furthermore, LAI was ameliorated using the T2 fertilizer scheme. Concerning plant diversity, a key finding in this study is that the O. dictamnus ecosystem favors herbaceous plant species richness and Shannon’s diversity index. In total, 18 plant species in the O. dictamnus ecosystem were recorded in the study area. The most frequently occurring plants were Anthemis arvensis L. and Piptatherum miliaceum (L.) Coss. Finally, the highest Shannon’s diversity index of herbaceous plants was detected using the T2 fertilizer scheme.

Mentha spicata L., Origanum dictamnus L., and Origanum onites L. are aromatic plants that produce very important essential oils. They are considered model plants with beneficial health properties due to their antioxidant content. Enhancing the yield while maintaining the quality of essential oil is of significant commercial importance. Salinization and drought cause various effects on the yield and quality of the bioactive constituents in essential oil. By assessing the response of these plants and their secondary metabolites accumulation to different salt stress and irrigation levels, this study aims to gain insights into how plants adapt to and cope with salinity and drought. A pot experiment was conducted in the spring of 2020 to assess the effect of salinity and drought stress on the growth and essential oils content of the three aromatic plant species mentioned above. The soil mixture used was perlite and peat in a ratio of 1:1:6, while four salinity treatments (25, 50, 100, and 150 mΜ NaCl) and two levels of irrigation were applied (100% and 50%). Salinity significantly affects total chlorophyll concentration especially in higher concentrations (100 and 150 mM) in M. spicata plants, especially under 50% soil water irrigation. Under the same conditions, M. spicata contained the higher proline concentration, which was significantly greater than that in O. dictamnus and O. onites. Similar variations of malondialdehyde and hydrogen hyperoxide were revealed among the three species, with significantly higher values in M. spicata when subjected to both excess salinity and drought conditions. The major compounds identified in M. spicata were carvone, in O. dictamnus carvacrol, and p-cymene and in O. onites carvacrol. It is important to highlight that O. onites had the highest concentration of essential oil, and that the concentration increased with the increase of NaCl. This suggests that the presence of NaCl in the soil may have a stimulating effect on the production of essential oil in O. onites. However, it is plausible that the stress caused by NaCl triggers a physiological response in O. onites, leading to increased production of essential oil. This could be a protective mechanism to enhance the plant’s resistance to the stressor. Overall, O. onites and O. dictamnus appeared to be more resistant to these stress conditions than M. spicata, since they maintained their growth and essential oil quality indicators at higher levels. These two species possess mechanisms that prevent or minimize lipid peroxidation, thus protecting their cell membranes and maintaining their ultrastructure integrity.

Cretan dittany (Origanum dictamnus L.) is an aromatic and medicinal plant, local endemic of the island of Crete, Greece, occurring naturally to high rocky mountain habitats. Due to its commercial interest, cultivation of this plant has been recently expanded. Since natural infestations by Meloidogyne spp. in field cultivated plants have not been found, its response to infection by M. javanica, M. incognita, M. arenaria, M. hapla and M. luci was investigated in pot experiments. In all experiments, roots of dittany plants exhibited neither galls nor egg masses in contrast to the roots of tomato plants used as controls. Therefore, Cretan dittany appears to be resistant to the five Meloidogyne species tested.

Origanum dictamnus L. (Lamiaceae), a local endemic plant of Crete (Greece), creates polysaccharide-containing subcuticular compartments presenting biological activity against phytopathogenic fungi, and, among others, significantly affects the fungal cell wall polysaccharides. This field study introduces a fertilization scheme for O. dictamnus, which was developed and refined to optimize the yield as well as critical herbal quality aspects. Five fertilization schemes were investigated, based on a polysaccharide-based Integrated Nutrient Management (INM), a mixture of conventional inorganic fertilizers (ChF) and two biostimulants (not algae) via foliar and soil application. Plant growth, together with leaf chlorophyll fluorescence and color (SPAD meter, DA meter, Chroma Meter) were determined. The leaf content of chlorophyll, three critical antioxidant compounds (carotenoids, flavonoids, phenols) and nutrients were also assessed. Considering all three antioxidants together, the enhanced efficiency, non-toxic, water-soluble, polysaccharide-based INM by foliar application was the most stimulatory scheme, playing an important role in plant growth and development. The present field study provides, for the first time, baseline fertilization data improving key herbal quality features in O. dictamnus and unravels the attainment of high antioxidant properties. The latter may be exploited in favor of its further utilization as a raw material for tea preparation, medicinal purposes, natural food flavoring and/or food preservative.

HPLC-PDA-MS profiling of Origanum dictamnus L. infusion and its encapsulation in electrospun nanofibers for oral administration

The use of synthetic sanitizers for fresh commodities preservation is of concern, with eco-friendly alternatives, including essential oils (EOs), attracting research and industry interest. Dittany (Origanum dictamnus—DIT) oil was applied, either through vapour or dipping, on pepper fruit or in vitro against Botrytis cinerea, and compared to untreated (control) or chlorine (CHL)-treated fruits stored at 11 °C. Direct DIT vapours (up to 6 d) suppressed lesion growth, spore germination, and spore production compared to the untreated fruits. The antimicrobial properties of EOs were evidenced in pre-exposed-to-DIT oil vapours (residual effect), resulting in fruit lesion suppression. However, DIT-pretreated fruits had the same spore production and spore germination as the control and CHL applications. In in vitro tests, DIT vapours decreased colony growth and spore production when fungi were grown on Potato Dextrose Agar (PDA) or PDA pre-exposed to DIT following B. cinerea inoculation. This evidenced that the disease suppression after DIT vapour application primarily affected the interaction of the fruit–pathogen and/or residual responses on fruit tissue and/or PDA media. Fungal biomass in Potato Dextrose Broth (PDB) was evaluated after DIT and CHL applications (10–50–100–500–5000 μL L−1) and decreased with the DIT oil. Additionally, DIT or CHL sanitary dipping on pepper was ineffective against B. cinerea compared to vapour application. Therefore, DIT vapours revealed antimicrobial properties and could be an alternative postharvest sanitiser. DIT oil application should also be evaluated at semi-commercial scale for further optimizations, prior to commercialisation.

The aim of the present brief review is to summarize the potential beneficial biological activities of several Greek herbs: Matricaria chamomilla (Asteraceae), Laurus nobilis (Lauraceae), Hypericum perforatum (Hypericaceae), Rosmarinus officinalis (Lamiaceae),Origanum dictamnus (Lamiaceae), Origanum majorana (Lamiaceae), Origanum vulgare (Lamiaceae), Sideritis syriaca (Lamiaceae), Salvia officinalis (Lamiaceae), Mentha pulegium (Lamiaceae), Satureja thymbra (Lamiaceae), and Thymus vulgaris (Lamiaceae). Through the exploration of their diverse biological activities and bioactive compounds, this brief review aims to contribute to the understanding of the therapeutic potential of Greek herbs in various industries, including traditional medicine, cosmetics, food preservation, and biopharmaceuticals.

Skin aging mainly occurs due to intrinsic and extrinsic factors. Extrinsic aging is a consequence of exposure to ultraviolet radiation. Meanwhile, natural products exhibit protective properties against skin aging as well as photoaging. In this context, the research on natural anti-aging agents is greatly advanced, and in recent years, numerous plant-based products have been investigated. The aim of this study was to assess the antioxidant profile of Origanum dictamnus L. extract as well as its antiaging effects on 2D cultures of fibroblasts and keratinocytes under UVA irradiation to unravel the potential role of Origanum dictamnus L. in cosmetology. In an attempt to explore the antioxidant profile of the extract, we employed well-established enzymatic assays (DPPH, FRAP, ABTS, and TPC) and a phytochemical screening by LC/MS. According to our findings, the Origanum dictamnus L. extract possesses high scavenging activity (DPPH, ABTS), high phenolic content (TPC), and high Fe(III)-reduction activity (FRAP). Moreover, the LC/MS analysis revealed that the extract was rich in flavonoids, holding a high content of curcumin, kampferol, silymarin, cyanidin-3-glucoside, deosmin, rutin, and quercetin. To gain insight into the bioactivity of Origanum dictamnus L. extract in cell aging, the expression of various genes that are implicated in the skin aging process in keratinocytes and fibroblasts was studied. The gene expression analysis revealed that the extract increases cell proliferation in the cells exposed to UVA irradiation and concomitantly modulates the expression of genes related to the aging process in keratinocytes (KLK7, OCLN, GBA1) and fibroblasts (SIRT2, FOXO3, COL3A1) under the same conditions.

Introduction: The need for effective therapeutic regimens for non-critically ill patients during the COVID-19 pandemic remained largely unmet. Previous work has shown that a combination of three aromatic plants’ essential oils (CAPeo) (Thymbra capitata (L.) Cav., Origanum dictamnus L., Salvia fruticose Mill.) has remarkable in vitro antiviral activity. Given its properties, it was urgent to explore its potential in treating mild COVID-19 patients in primary care settings. Methods: A total of 69 adult patients were included in a clinical proof-of-concept (PoC) intervention study. Family physicians implemented the observational study in two arms (intervention group and control group) during three study periods (IG2020, n=13, IG2021/22, n=25, and CG2021/22, n=31). The SARS-CoV-2 infection was confirmed by real-time PCR. The CAPeo mixture was administered daily for 14 days per os in the intervention group, while the control group received usual care. Results: The PoC study found that the number and frequency of general symptoms, including general fatigue, weakness, fever, and myalgia, decreased following CAPeo administration. By Day 7, the average presence (number) of symptoms decreased in comparison with Day 1 in IG (4.7 to 1.4) as well as in CG (4.0 to 3.1), representing a significant decrease in the cumulative presence in IC (−3.3 vs. −0.9, p < 0.001; η2 = 0.20) on Day 7 and on Day 14 (−4.2 vs. −2.9, p = 0.027; η2 = 0.08). Discussion/Conclusions: Our findings suggest that CAPeo possesses potent antiviral activity against SARS-CoV-2 in addition tο its effect against influenza A and B and human rhinovirus HRV14 strains. The early and effective impact on alleviating key symptoms of COVID-19 may suggest this mixture can act as a complementary natural agent for patients with mild COVID-19.

This study examined five species of the Lamiaceae family, Origanum vulgare L., Origanum dictamnus L., Origanum majorana L., Mentha spicata L. and Lavandula angustifolia L., and one species of the Hypericaceae family, Hypericum perforatum L., for their potential to enhance health and wellbeing or to prevent diseases. An analysis of secondary metabolites was performed by mass spectrometry and HPLC coupled with diode array detection to determine the phenolic compounds included in the plant extracts. The samples were evaluated for their total phenolic content, antioxidant potential, ability to prevent DNA scission caused by peroxyl radicals and antimicrobial activity against pathogens (MIC). All the samples, except Lavandula angustifolia L., had a high DPPH radical scavenging activity and showed significant antibacterial activity. Origanum majorana L. demonstrated the lowest IC50 value (10.31 μg·mL−1). Extracts of medicinal herbs had a remarkably high phenolic content varying between 428 and 1512.74 μg GAE/mg of dry extract, with Origanum vulgare L. having the largest amount of polyphenols. Moreover, the plant extracts exhibited a high level of resistance against DNA damage, with Origanum majorana L. showing the greatest level of protection with 98.05% inhibition. According to the results of this study, these plants from the Greek flora provide beneficial effects for health as natural antioxidants. A baseline can be established through the analysis of the findings of this survey for future research on the same plant species.